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osteology and osteological variation of the species within the E. orcesi Group, ... words: Eleutherodactylus orcesi Group; Leptodactylidae; Monophyly; Osteology.
Herpetological Monographs, 18, 2004, 142–174 Ó 2004 by The Herpetologists’ League, Inc.

THE ELEUTHERODACTYLUS ORCESI SPECIES GROUP (ANURA: LEPTODACTYLIDAE): COMPARATIVE OSTEOLOGY AND COMMENTS ON ITS MONOPHYLY JUAN M. GUAYASAMIN1 1

Natural History Museum & Biodiversity Research Center, Department of Ecology and Evolutionary Biology, The University of Kansas, Lawrence, Kansas 66045-7561, USA ABSTRACT: The anuran genus Eleutherodactylus occurs in Central and South America, as well as the West Indies, and comprises nearly 700 recognized species. The diversity of Eleutherodactylus makes it difficult to study the genus as a whole; as a consequence, several authors have divided the genus in phenetic species groups. This division is based on similarity and is not necessarily congruent with monophyletic groups within the genus. Nevertheless, species groups can be considered as hypotheses of natural (monophyletic) groups. I focus on the E. orcesi Group, which contains eight species distributed in the paramo and montane forests (3000–4150 m) of Colombia and Ecuador. The main objectives in the present study are to: (1) describe the osteology and osteological variation of the species within the E. orcesi Group, (2) diagnose the group based on osteological characters, and (3) search for homologies that might support the monophyly of the group. Osteological descriptions for the eight species were made from cleared-and-double-stained specimens. To minimize effects of heterochrony and sexual dimorphism, only adult females were examined. To determine the validity of potential synapomorphies of the E. orcesi Group, I examined cleared-and-stained specimens of 135 species of Eleutherodactylus and used published information for another 29 species. The skulls of all the species of the Eleutherodactylus orcesi Group have a large portion of the frontoparietal fontanelle exposed anteromedially. I hypothesize that the presence of an exposed frontoparietal fontanelle is homologous in the E. orcesi Group and supports the monophyly of the group. I discuss the presence of this character in species outside the E. orcesi Group and hypothesize that in those species the exposed fontanelle was acquired independently. I provide a list of diagnostic characters for the E. orcesi Group and discuss the variation of some of these characters in relation to the general pattern of morphology found in the genus Eleutherodactylus and other anurans. Finally, I discuss intraspecific variation in several osteological characters of the cranium and postcranium of species of the E. orcesi Group, especially E. racemus. Key words: Eleutherodactylus orcesi Group; Leptodactylidae; Monophyly; Osteology.

CURRENT GROUPING of frogs in the genus Eleutherodactylus is mostly phenetic (but see Lynch, 1986, 1992, 1997, 1999). Similarity does not test a hypothesis of homology, but validates it as worthy of testing (Patterson, 1982); therefore, species groups based on morphological similarity can be considered as hypotheses of natural (monophyletic) groups. One of the problems in testing the monophyly of species groups in Eleutherodactylus is the diversity of the genus which currently includes 689 described species (Frost, 2002). This species richness also encompasses a wide range of morphological complexity. These factors, along with the lack of clear diagnostic characters for the species groups and the few osteological descriptions available, make it extremely difficult to test hypotheses of homology and monophyly. As a first step, we need to know if CORRESPONDENCE: e-mail, [email protected]

unique characters support the monophyly of species groups within Eleutherodactylus. Herein, I focus on species of the Eleutherodactylus orcesi Group, first recognized by Lynch (1981a) for an assemblage of species living in paramo and montane forests (3000– 4150 m) of Colombia and Ecuador. This group currently contains eight species: E. huicundo Guayasamin et al. 2004; E. obmutescens Lynch 1980; E. orcesi Lynch 1972; E. ortizi Guayasamin et al. 2004; E. racemus Lynch 1980; E. simoteriscus Lynch et al. 1996; E. simoterus Lynch 1980; and E. thymelensis Lynch 1972. Species of the Eleutherodactylus orcesi Group are included in the E. martinicensis Series, which is proposed to be monophyletic by having Toe V much longer than Toe III (Lynch and Duellman, 1997). The E. martinicensis Series contains 186 species distributed throughout the West Indies (except Jamaica) and northwestern South America (Lynch and Duellman, 1997).

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The main objectives of the present study are to: (1) describe the osteological variation within the species of the Eleutherodactylus orcesi Group; (2) diagnose the group based on osteological characters; and (3) search for homologies that might support the monophyly of the group. MATERIALS AND METHODS I examined cleared-and-stained or clearedand-double-stained (C&S) specimens of frogs from the herpetological collections at the Natural History Museum of The University of Kansas (KU), Museo de Zoologı´a of the Universidad Cato´lica del Ecuador (QCAZ), and Instituto de Ciencias Naturales of the Universidad Nacional de Colombia (ICN). Osteological descriptions are based on C&S specimens of the eight species currently included in the Eleutherodactylus orcesi Group. To minimize possible effects of heterochrony and sexual dimorphism, only adult females were examined (Table 1). Techniques for clearing and double-staining specimens with Alcian Blue and Alizarin Red were modified from those of Taylor and Van Dyke (1985). Illustrations were made with the aid of a Leica MZ12 stereo dissecting microscope equipped with a camera lucida. Osteological terminology is that of Duellman and Trueb (1986), Fabrezi (1992, 1993), and Trueb (1973, 1993). The following cranial measurements were taken as described in Trueb (1977; Fig. 1): (1) medial head length; (2) lateral head length; (3) head width at angles of jaw; (4) head width at level of premaxillae; (5) head width at level of pterygoids; (6) pterygoid–maxillary length; (7) nasal length; (8) height of alary process of premaxillae; (9) greatest height of skull; (10) preorbital height of skull; and (11) greatest width of occipital condyles. Additionally, I measured: (12) parasphenoid length, the distance from anterior end of cultriform process to posterior end of posterior process; and (13) parasphenoid width, the distance between the most lateral margins of parasphenoid alae. Because osteological characters are difficult to measure properly in C&S specimens, I obtained all measurements from drawings produced with a camera lucida; although this might produce some inaccuracies in the measurements (in mm), this problem is reduced when proportions are obtained.

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To estimate intraspecific variation of osteological characters, I examined five C&S adult females (KU 168948, 170158–61) of Eleutherodactylus racemus and two C&S adult females (KU 117722–23) of E. thymelensis. To determine intraspecific variation of the number of presacral vertebrae and relative length and orientation of transverse processes, I examined five C&S females and radiographs of 10 additional adult females (KU 168941, 168945–47, 168949, 168950, 168964–66, 168968; Appendix I) of E. racemus; radiographs were taken with a TFI Corporation Unit at 5 mA and 50 kV for 45–60 s using Kodak’s Industrex SR film. Sexual maturity of females was determined by the presence of eggs or convoluted oviducts. A complete osteological description for E. huicundo is provided; for the rest of the species, only variation in relation to E. huicundo is noted. To determine the occurrence of the exposed frontoparietal fontanelle and its validity as a synapomorphy of the E. orcesi Group, I examined most of the C&S adult males and/or adult females of Eleutherodactylus from South America, and some from Central America and the West Indies housed in the KU collection (specimens of 135 species; Appendix II); additionally, I used published information for another 29 species (see Results: Distribution of the Exposed Frontoparietal Fontanelle in Eleutherodactylus). For ease of comparison, the diagnosis of the E. orcesi Group follows that of Lynch (1971:144–147) for the genus Eleutherodactylus. The following abbreviation is used: SVL 5 snout–vent length. RESULTS ELEUTHERODACTYLUS HUICUNDO (QCAZ 14746) CRANIAL OSTEOLOGY The ossified skull (Figs. 2, 3A, 4A, 5A) of Eleutherodactylus huicundo is smooth (i.e., no exostosis), as wide as long (lateral head length 5 head width at angles of jaw), and with a maximum height that is about 41% of its lateral length. The maximum width of the skull is at the posterior level of the maxillae (Figs. 2A, 2B, 3A, 4A). A moderately large frontoparietal fenestra lies between the anteromedial margins of the frontoparietals and the posteromedial margin of the sphenethmoid. Septomaxillae and stapes are present. Each septomaxilla is

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TABLE 1.—SVL and cranial measurements (mm) of adult females of the Eleutherodactylus orcesi Group. In E. racemus, range is followed by mean and standard deviation. E. huicundo E. obmutescens

Museum number SVL Medial head length

QCAZ 14746 28.7 8.6

KU 144090 35.2 10.8

Lateral head length

9.5

12.6

Head width at angles of jaw

9.5

14.0

Pterygoid-maxillary length

5.9

7.5

Nasal length

2.5

3.1

Head width at level of premaxillae Head width at level of pterygoids Greatest width of occipital condyles Height of alary process

2.6

2.9

9.0

11.8

2.8

3.6

1.9

2.2

Preorbital height of skull

3.0

4.4

Greatest height of skull

3.9

6.6

Parasphenoid length

6.2

7.0

Parasphenoid width

5.3

7.2

E. orcesi

E. ortizi

E. racemus

KU QCAZ KU 168948, 177814 14779 170158–61 34.0 26.7 33.7–39.0 10.1 8.8 9.3–11.3 10.0 6 0.76 11.2 9.8 10.2–13.3 11.6 6 1.10 11.6 11.2 11.6–14.5 12.6 6 1.13 6.8 6.1 6.2–7.5 6.8 6 0.48 2.9 2.1 2.6–3.2 2.9 6 0.28 2.7 2.4 2.5–3.5 3.0 6 0.37 10.5 9.7 9.8–12.9 11.0 6 1.16 3.4 2.9 2.8–3.9 3.2 6 0.41 2.6 1.5 1.6–1.9 1.7 6 0.15 3.1 2.5 3.2–4.1 3.6 6 0.35 5.0 3.8 4.5–5.8 5.0 6 0.58 5.8 5.2 5.9–6.6 6.2 6 0.30 5.8 5.1 5.8–6.6 6.2 6 0.35

comma-shaped and has an elongate process that projects posteriorly from its anteromedial margin. Dermal investing bones are more ossified than neurocranial elements. Snout– vent length and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—The paired sphenethmoids (Figs. 2, 3A, 4A, 5A) are fused dorsoand ventromedially to form a single element that is exposed dorsally between the frontoparietals and the nasals. Ventrally, the sphenethmoid partially subtends the neopalatines, cultriform process of the parasphenoid, and posterior portions of the vomers. In dorsal view, the sphenethmoid projects anteriorly but does not reach the level of the anterior margins of the nasals; the anteromedial margin of the sphenethmoid lies about 1/2 the distance from the anterior margin of the frontoparietal fontanelle to the end of snout. The posteromedial margin of the sphenethmoid is slightly sinuous. Posterolaterally, the sphenethmoid

E. simoteriscus E. simoterus E. thymelensis

ICN 22837 36.0 11.2

ICN 18821 40.0 11.4

KU 117722–3 34.0, 29.9 11.2, 9.0

12.5

13.2

12.6, 10.7

13.2

14.5

13.4, 11.1

7.1

7.6

7.9, 6.1

2.9

2.7

2.5, 2.4

3.4

4.1

3.0, 2.8

11.8

12.5

11.8, 9.3

3.6

4.1

3.2, 2.9

2.0

2.2

2.4, 1.8

3.6

4.1

4.1, 3.7

5.2

5.7

6.2, 4.8

6.5

6.1

7.2, 5.1

6.3

5.9

7.0, 5.1

forms the anterior portion of the lateral wall of the braincase. The sphenethmoid forms the anterior margin of the optic fenestra; the anterodorsal and ventral margins are cartilaginous. In ventral view (Fig. 4A), the anterior margin of the sphenethmoid reaches the level of the anterior one-fourth of the vomers, where it is united with the cartilage of the solum nasi. The orbitonasal foramen opens through the sphenethmoid at the inflection point of the anteromedial border of the orbit, at a level slightly anterior to the terminus of the cultriform process of the parasphenoid. Prootics and exoccipitals.—Each prootic (Figs. 2, 3A, 4A, 5A) forms most of the otic capsule and the posterior and posterodorsal margins of the optic fenestra. In dorsal view (Fig. 3A), the prootics are invested dorsomedially by the frontoparietals. Dorsolaterally, each prootic terminates in a narrow, cartilaginous crista parotica, which is invested dorsally by the otic ramus of the squamosal. The oculomotor and prootic foramina are completely enclosed by the ossified prootics.

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FIG. 1.—Cranial measurements taken in species of the Eleutherodactylus orcesi Group. Dorsal (A), ventral (B), and lateral (C) views. HLM, medial head length; HLL, lateral head length; HWJ, head width at levels of jaw; HWPM, head width at level of premaxillae; HWPT, head width at level of pterygoid; PTML, pterygoid-maxillary length; NL, nasal length; HAP, height of alary process; GHTS, greatest height of skull; PHT, preorbital height of skull; CWO, greatest width of occipital condyles; PL, parasphenoid length; PW, parasphenoid width. Stippling denotes ossification; gray denotes cartilage; black denotes foramina or fenestrae.

The fused exoccipitals form the posteriormost portion of the neurocranium, including the posteromedial part of the otic capsule, the bone around the foramen magnum, and the occipital condyles. In dorsal view, the posteromedial borders of the exoccipitals, between the occipital condyles, have a semicircular shape posteriorly. The occipital condyles have round articular surfaces and are widely separated. Dermatocranium Nasals.—The paired, small nasals (Figs. 2, 3A, 5A) form the roof of the olfactory capsules. Medially, the nasals are separated

from each other; this separation is more pronounced posteriorly. The medial border of each nasal overlies most of the anterolateral portion of the sphenethmoid. The anterior margin of each nasal is slightly sinuous and does not articulate with the alary process of the premaxilla. The posterior margin is approximately horizontal and partially overlaps the planum antorbitale. The maxillary process does not reach the preorbital process of the maxilla laterally. The ventrolateral margin of each nasal is ventrally concave and broadly separated from the pars facialis of the maxilla. The nasals do not articulate with the frontoparietals.

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FIG. 2.—Skull of adult female of Eleutherodactylus huicundo, QCAZ 14746, SVL 5 28.4 mm. Dorsal (A), ventral (B), and lateral (C) views. Stippling denotes ossifications; gray denotes cartilage; black denotes foramina or fenestrae.

Frontoparietals.—The paired frontoparietals (Figs. 2, 3A, 4A, 5A) do not articulate along the midline. They diverge antero- and posteromedially from one another, exposing the frontoparietal fontanelle anteromedially. In dorsal view, the lateral margin of each frontoparietal is longitudinally straight. Each frontoparietal slightly expands laterally in its posterior portion. Anterolaterally, each frontoparietal invests the dorsolateral margin of the sphenethmoid and each is broadly separated from the nasals. In transverse section, the frontoparietals are flat and lack cranial crests. Ventrolaterally, each bone bears a lamina perpendicularis, which does not contribute to the dorsal margin of the optic fenestra. The frontoparietals do not fuse with the prootic and the frontoparietal-prootic sutures are evident. Parasphenoid.—The T-shaped parasphenoid (Figs. 2B, 2C, 4A) invests the neurocranium ventrally; its maximum width is about 85% of its length. The cultriform process is

widest posteriorly, narrowing anteriorly; the parasphenoid ventrally invests approximately 56% of the bony sphenethmoid, and extends anteriorly nearly to the level of the neopalatines and the vomers. The anterior terminus of the cultriform process is irregular and non-acuminate. The parasphenoid alae project posterolaterally from the longitudinal axis at approximately 958. The ventral surface of each parasphenoid ala is smooth and lacks ridges; laterally, each ala ventrally invests the ossified portion of the fused prootic and exoccipital, reaching the level of, but lying posterior to, the medial ramus of the pterygoid. The parasphenoid has a long acuminate posteromedial process that is narrowly separated from the posterior margin of the exoccipital and does not contribute to the margin of the foramen magnum. Vomers.—The paired vomers (Figs. 2B, 4A) contribute to the floor of the nasal capsules. They are positioned obliquely with respect to

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FIG. 3.—Dorsal view of cranium of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. obmutescens, KU 144090. (C) E. orcesi, KU 177814. (D) E. ortizi, QCAZ 14779. (E) E. racemus, KU 168948. (F) E. simoteriscus, ICN 22837. (G) E. simoterus, ICN 18821. (H) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage; black denotes foramina. Scale bars 5 2 mm.

the longitudinal axis of the cranium and distinctly separated from one another and the adjacent maxillae and premaxillae of the upper jaw. Each vomer has pre- and postchoanal processes and a dentigerous process. The triangular prechoanal process is well developed and has a non-serrate posterolateral margin; the postchoanal process is relatively well developed, slender, and oriented posterolaterally. The elongated dentigerous process

extends posteromedially to the level of the neopalatines, near the anterior margin of the cultriform process. Two vomerine teeth are present on the narrow dentigerous process of the left vomer and none on the process of the right vomer. Premaxillae.—These paired elements form the anteriormost segments of each maxillary arch. The premaxillae (Figs. 2, 14A, 15A, 16A, 17A) are narrowly separated from one another

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FIG. 4.—Ventral view of cranium of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. obmutescens, KU 144090. (C) E. orcesi, KU 177814. (D) E. ortizi, QCAZ 14779. (E) E. racemus, KU 168948. (F) E. simoteriscus, ICN 22837. (G) E. simoterus, ICN 18821. (H) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage; black denotes foramina. Scale bars 5 2 mm.

medially. Each premaxilla is laterally invested by the pars facialis of the maxilla. The premaxilla is composed of a pars dentalis, alary process, and pars palatina. There are 12 pedicellate, bicuspid teeth on each premaxilla; the teeth are longer than wide and slightly curved. The alary process extends posterodorsally; its dorsal portion is wider than the base, and the terminus is conspicuously notched (Fig. 6A). Each pars palatina bears a rectangular posterolateral and a triangular

posteromedial process. The posteromedial processes do not articulate with one another along the midline. Maxillae.—The paired maxillae (Figs. 2, 3A, 4A, 5A) are the largest bony elements of the maxillary arcade. Each bone bears distinct partes dentalis, facialis, and palatina. The pars dentalis of each maxilla extends from the maxillary-premaxillary border to the articulation between the maxilla and anterior ramus of the pterygoid and bears approximately 50

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FIG. 5.—Lateral view of cranium of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. obmutescens, KU 144090. (C) E. orcesi, KU 177814. (D) E. ortizi, QCAZ 14779. (E) E. racemus, KU 168948. (F) E. simoteriscus, ICN 22837. (G) E. simoterus, ICN 18821. (H) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage; black denotes foramina. Scale bars 5 2 mm.

pedicellate teeth. The pars facialis of the maxilla invests the pars facialis of the premaxilla anterolaterally (Fig. 6A). The pars facialis of each maxilla projects anterodorsally, but does not articulate with the alary process of the premaxilla; the pars facialis has a moderatesized preorbital process that does not articulate with the maxillary process of the nasal; postorbital and pterygoid processes are absent. In ventral view (Fig. 4A), the anterior border of the pars palatina does not articulate with the pars palatina of the premaxilla. Posteriorly, the pars palatina extends to the posterior margin of the maxilla–pterygoid articulation. In ventral view (Fig. 4A), the posteromedial border of the pars palatina does not overlap the posterolateral border of the anterior ramus of the pterygoid. The maxilla does not articulate with the nasal or the zygomatic ramus of the squamosal; laterally, the posterior terminus of the maxilla invests the anterior third of the quadratojugal.

Quadratojugals.—The paired quadratojugals (Figs. 2, 3A, 4A, 5A) complete the posterior portion of the maxillary arcade. Each quadratojugal extends anteriorly for about two-thirds the length of the pterygoid fossa and invests the posterior ramus of the maxilla medially. Posterolaterally, the quadratojugal is partially invested dorsally by the ventral ramus of the squamosal; posteroventrally, the pars articularis of the palatoquadrate cartilage invests the quadratojugal. Neopalatines.—The paired neopalatines (Figs. 2, 4A) invest the ventral surfaces of the planum antorbitale at the anteroventral margin of the orbit. The neopalatines have a slightly curved shape. Each neopalatine is relatively short and ventrally invests about one sixth of the ventrolateral surface of the sphenethmoid, via a slender, acuminate process. The lateral terminus of the neopalatine is twice as wide as the midbody of this element. The neopalatine articulates with the pars palatina of the maxilla,

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TABLE 2.—Proportions (%) between cranial measurements of adult females of the Eleutherodactylus orcesi Group. E. E. huicundo obmutescens

Museum number

QCAZ 14746

Medial head length/ Head width at angles of jaw 91.0 Lateral head length/ Head width at angles of jaw 100.0 Pterygoid-maxillary length/ Medial head length 68.6 Pterygoid-maxillary length/ Head width at angles of jaw 62.4 Nasal length/Medial head length 28.9 Head width at level of premaxillae/ Head width at angles of jaw 27.8 Head width at level of pterygoids/ Medial head length 104.1 Head width at level of pterygoids/ Head width at angles of jaw 94.7 Greatest width of occipital condyles/ Head width at angles of jaw 29.3 Height of alary process/ Greatest height of skull 47.2 Preorbital height of skull/ Greatest height of skull 76.2 Greatest height of skull/ Medial head length 45.6 Greatest height of skull/ Head width at angles of jaw 41.4 Parasphenoid length/ Medial head length 71.2 Parasphenoid length/ Head width at angles of jaw 64.7 Parasphenoid length/ Parasphenoid width 117.1 Parasphenoid width/ Medial head length 60.7 Parasphenoid width/ Head width at angles of jaw 55.3

KU 144090

E. orcesi

E. ortizi

E. racemus

KU QCAZ KU 168948, 177814 14779 170158–61

E. E. simoteriscus simoterus

E. thymelensis

ICN 22837

ICN 18821

KU 117722–3

77.3

86.7

78.6

77.6–82.4

84.8

78.6

83.5, 81.6

89.6

96.1

87.6

87.9–97.5

94.7

91.0

94.5, 96.5

68.9

67.6

69.3

66.7–69.5

63.4

66.7

70.8, 67.9

53.2 28.6

58.6 28.8

54.5 23.7

51.7–56.9 26.6–32.0

53.8 25.9

52.4 23.7

59.1, 55.3 22.6, 26.1

20.8

23.4

21.4

21.6–25.0

25.8

28.3

22.1, 24.9

109.2

103.6

84.4

89.8

86.9

84.5–88.8

89.4

86.2

88.2, 83.6

25.3

28.9

25.5

22.6–26.7

27.3

28.3

23.6, 26.2

33.9

50.9

38.8

32.1–35.6

38.5

38.6

38.5, 37.4

67.8

61.8

67.2

67.3–73.9

69.2

71.9

66.2, 77.3

60.6

49.5

42.9

45.0–56.7

46.4

5.7

55.5, 53.7

46.8

43.0

33.7

35.2–46.7

39.4

39.3

46.3, 43.8

64.2

57.7

59.3

57.5–66.0

58.0

53.5

64.2, 56.5

49.6

50.0

46.6

44.6–51.6

49.2

42.1

53.5, 46.1

97.1

100.0

102.6

95.3–103.4

103.2

66.2

57.7

57.8

57.3–66.0

56.3

51.8

62.3, 56.5

51.1

50.0

45.4

44.6–52.6

47.7

40.7

52.0, 46.1

but a posterolateral gap is evident. This gap is occupied by cartilage of the planum antorbitale. Each neopalatine bears a ventral triangular ridge that extends from its distal end to its midpoint. Suspensorium In the adult anurans, the suspensory apparatus functions to brace and suspend the jaws against the neurocranium (Trueb, 1973). It is composed of the squamosals and pterygoids. Squamosals.—Each squamosal (Figs. 2, 3A, 4A, 5A) has three rami. The relative lengths of the rami are: ventral > otic > zygomatic. The zygomatic ramus does not articulate with other bones of the skull and extends anteroventrally, terminating in an acuminate point. The ventral

110.5 104.3–113.0

105.4

109.6 106.0, 102.6

103.4 103.0, 100.0

ramus expands posteroventrally at approximately 458 from the longitudinal axis of the quadratojugal. In lateral view (Fig. 5A), the posterior margin of each ventral ramus is concave proximally and supports part of the tympanic annulus; distally, the posterior margin of each ventral ramus is convex. The otic ramus extends posterodorsally and invests the crista parotica dorsally. Pterygoids.—The paired pterygoids (Figs. 2, 3A, 4A, 5A) are edentate and triradiate, with anterior, medial, and posterior rami. The anterior ramus extends anterolaterally to articulate with the maxilla at a level anterior to the midpoint of the orbit and is separated from the neopalatine; the anterior ramus has a channel along the dorsolateral surface that

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FIG. 7.—Dorsal (A) and lateral (B) views of mandible of Eleutherodactylus huicundo, QCAZ 14746, /. Stippling denotes ossification; gray denotes cartilage. Scale bar 5 2 mm.

FIG. 6.—Anterior view of premaxillae of adult females of Eleutherodactylus huicundo (A) QCAZ 14746, and of E. ortizi (B) QCAZ 14779. Stippling denotes ossification. Scale bars 5 1 mm.

accommodates the pterygoid process of the palatoquadrate cartilage. The medial ramus of each pterygoid extends to the ventrolateral surface of the prootic; it does not articulate with the parasphenoid ala. The posterior ramus extends posterolaterally and invests the posteromedial portion of the palatoquadrate cartilage (pars articularis) and the ventral ramus of the squamosal. Mandibles Each edentate mandibular ramus (Fig. 7) is composed of the mentomeckelian, dentary, and angulosplenial bones. The small, paired mentomeckelian bones are syndosmotically united at the mandibular symphysis. Each dentary articulates with the anterodorsal portion of the mentomeckelian and extends posterolaterally for about 33% the length of the mandible, investing the dorsolateral margin of Meckel’s cartilage. The angulosplenial extends for about 90% the length of the mandible; laterally, it has a groove that bears Meckel’s cartilage; posteriorly, the angulosplenial broadens to form a concave surface where Meckel’s cartilage articulates with the pars articularis of the palatoquadrate cartilage.

Hyobranchial Apparatus The hyoid apparatus (Fig. 8A) is composed of a cartilaginous hyoid plate that bears a pair of posterolateral and posteromedial processes. The corpus of the hyoid plate is about as wide as long, lacks anterolateral alary processes, and is mineralized posteromedially (Fig. 8A). The hyoglossal sinus is broad and U-shaped. The cartilaginous hyalia are slender and project anteriorly from the anterolateral margin of the hyoid plate and curve posterodorsally to attach to the ventral surface of the otic capsule; each hyale bears a long anterior process that is about 110% of the median length of the hyoid plate. The cartilaginous posterolateral processes are small and straight, and extend posteriorly from the posterior corners of the hyoid plate; posteriorly, the posterolateral processes do not reach the level of the posterior margin of the hyoid plate. The posteromedial processes are ossified and directed posterolaterally and their length is about 119% of the median length of the hyoid plate. Each process is wider at the ends than at midshaft. The proximal heads do not articulate with each other medially and are wider than the distal heads; the distal head terminates in cartilage; each posteromedial process has a nearly straight medial border and a concave lateral border. POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS HUICUNDO Axial system.—The vertebral column (Figs. 9A, 10A) is composed of eight procoelous presacral vertebrae, the sacrum, and the

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urostyle. Presacral vertebrae are non-imbricate; free ribs are absent. Dorsal ossification of neural arches is complete in all presacrals. In dorsal view (Fig. 9A), the anterior margins of neural arches are anteriorly concave in all presacrals, except Presacral II, which also has a process that extends anteriorly and almost articulates with Presacral I. The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > V ’ VI ’ VII ’ VIII > II. The orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral VIII, directed anterolaterally in Presacral II, and posterolaterally in Presacrals III–VII. Neural spines are not evident. Presacrals II–VIII and the sacrum have prominent prezygapophyses that articulate ventrally with the postzygapophyses of the preceding vertebra; postzygapothyses are lacking on the sacrum; however, the sacrum has a bicondylar articulation with the urostyle. Presacral I (Fig. 11) bears widely spaced cervical cotyles (Type I; Lynch, 1971); the cotyles are not stalked and the atlas is not fused with Presacral II. Dorsally, the sacrum bears a transverse ridge that does not extend on the diapophyses. The sacral diapophyses extend posterolaterally and are only slightly expanded distally. The distal ends of the sacral diapophyses are cartilaginous and overlie the anterior ends of the ilial shafts, forming a TypeIIB articulation (Emerson, 1979). A calcified sesamoid lies on the lateral surface of the lateral margin of each sacral diapophysis (Fig. 9A); the sesamoid length equals the width of the head of the sacral diapophyses. The urostyle is 105% the length of the presacral vertebral column (measured from the anteriormost margin of Presacral I to the posteriormost margin of Presacral VIII) and bears a well-developed longitudinal ridge that decreases in height posteriorly. Pectoral girdle.—The ossified elements of the pectoral girdle (Fig. 12A) are the clavicle, coracoid, scapula, and cleithrum, whereas the cartilaginous elements are the sternum, omosternum, epicoracoid, procoracoid, and suprascapula. The curved epicoracoids overlap broadly and are fused at the epicoracoid bridge, which lies anterior to the medial ends of the clavicles, at the base of the omosternum. The procoracoid cartilages are continuous with the epicoracoid cartilages medially, and nar-

[No. 18

FIG. 8.—Ventral view of hyoid apparatus of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. orcesi, KU 177814. (C) E. racemus, KU 168948. (D) E. simoteriscus, ICN 22837. (E) E. simoterus, ICN 18821. (F) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Scale bars 5 2 mm.

row laterally, bordering the entire posterior edge of the clavicle. The pectoral fenestra is formed by the procoracoid anteriorly, epicoracoid medially, and coracoids posteriorly. The cartilaginous, posteriorly bifurcated sternum is flat plate and has a maximum width that is about 118% its maximum length. The bifurcation extends through the posterior third of the sternum. The cartilaginous omosternum is arrow-shaped, flat and wide (width 5 120% length); its style is not bifurcated. The clavicles are slender, slightly concave anteriorly, and narrowly separated medially by the epicoracoid bridge. The lateral end of the clavicle articulates broadly with the pars acromialis of the scapula and is distinctly separated from the coracoid posteriorly. The lateral end of each clavicle is about five times wider than the medial end. The anterior margin of the

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153

FIG. 9.—Dorsal view of axial skeleton and pelvic girdle of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. orcesi, KU 177814. (C) E. ortizi, QCAZ 14779. (D) E. racemus, KU 168948. (E) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage. Pelvic girdle removed in E. racemus. Scale bars 5 2 mm.

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[No. 18

FIG. 10.—Ventral view of axial skeleton and pelvic girdle of adult females of E. huicundo (A), QCAZ 14746, and E. ortizi (B), QCAZ 14779. Stippling denotes ossification; gray denotes cartilage. Scale bars 5 2 mm.

coracoid is clearly concave, whereas the posterior margin is nearly straight. The glenoid end of the coracoid is slightly more expanded than the sternal end. The scapulae are narrow and bicapitate; the anterior margin of the scapula is anteriorly concave and the posterior margin nearly straight; medially, the pars acromialis broadly articulates with the clavicle and the pars glenoidalis articulates with the coracoid. The distal end of each scapula is expanded and articulates with the cartilaginous suprascapula (Fig. 13), which is distally expanded. Each suprascapula possesses two mineralized rami: a broad ramus along the anterior margin that narrows distally, and a smaller posterior ramus along the posterior margin. The elongated cleithrum is well ossified and occupies the anterior margin of the suprascapula; it does not articulate with the scapula medially (Fig. 13). Pelvic girdle.—The pelvic girdle (Figs. 9A, 14A) consists of paired, ossified ilia, ischia, and highly mineralized pubes. The internal margins of the ilia have a V-shape in dorsal view.

FIG. 11.—Posterior (A) and anterior (B) views of Presacral I of Eleutherodactylus ortizi, QCAZ 14779, /. Stippling denotes ossification; gray denotes cartilage. Scale bar 5 1 mm.

Each ilial shaft has a low longitudinal crest and a dorsal protuberance. Posteriorly, the ilia are fused medially to form the anterior half of the almost circular acetabula; each ilium articulates and fuses with an ischium posteriorly and a pubis ventrally. The ischia are fused medially and form the posterior margin of the acetabula. Each ischium bears a short process at the point of articulation with the ilium; in lateral view, the posterior margin of the ischia is posteriorly concave. The pubis forms the ventral margin of the acetabulum. The centrum of the acetabulum is not completely ossified. Manus.—The manus (Fig. 15A) has six ossified carpal elements: ulnare, radiale, Carpal 2, Carpal 3-4-5, Element Y, and proximal prepollex (Morphology C; Fabrezi, 1992; her Fig. 1C). The relative sizes of the carpal elements are: Carpal 3-4-5 > ulnare > radiale

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155

FIG. 12.—Ventral view of pectoral girdle of adult females of species of the Eleutherodactylus orcesi Group. (A) E. huicundo, QCAZ 14746. (B) E. obmutescens, KU 144090. (C) E. orcesi, KU 177814. (D) E. racemus, KU 168948. (E) E. simoteriscus, ICN 22837. (F) E. simoterus, ICN 18821. (G) E. thymelensis, KU 117722. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Humerus removed, except in (E) and (F). Scale bars 5 2 mm.

> Element Y > Carpal 2 ’ proximal prepollex. Carpal 3-4-5 is articulates with all other carpal elements, except the proximal prepollex. The ulnare is slightly larger than the radiale and distally articulates with Carpal 3-4-5. Distal to the radiale are Element Y and part of Carpal 34-5. Three carpal elements are positioned

distal to Element Y: Carpal 2, proximal prepollex, and part of Carpal 3-4-5. The prepollex is formed by two elements, the proximal element is approximately spherical and completely calcified. The elongated distal element of the prepollex is larger than the proximal and highly mineralized proximally,

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FIG. 13.—Dorsal view of suprascapula of E. huicundo (A), QCAZ 14746, /, and E. simoteriscus (B), ICN 22837, /. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Scale bars 5 1 mm.

remaining cartilaginous distally (Fig. 15A). The relative lengths of the digits are: IV > V > III > II; the phalangeal formula is 2-2-3-3. The distal phalanges are T-shaped and slightly curved ventrally. Pes.—The tarsal morphology (Fig. 16A) resembles that of other leptodactylid frogs as described by Fabrezi (1993). The tibiale and fibulare are fused at the distal ends. The relative sizes of the tarsal elements are: distal tarsal 2-3 > Element Y ’ proximal prehallux > distal tarsal 1. Metatarsal V and IV articulate with the distal end of the fibulare. Tarsal 2-3 articulates with Metatarsals II and III. Tarsal 1 articulates with Metatarsals I and II. The prehallux and Tarsal 1 are positioned distal to Element Y. The prehallux is composed of two or three elements; the two proximal elements are calcified, whereas the distal element, if present, is minute and cartilaginous. A relatively large, calcified sesamoid element lies ventral to the articulation between Metatarsals V and IV and the fibulare. The relative lengths of the digits are: IV > V > III > II > I; the phalangeal formula is 2-2-3-4-3. The terminal phalanges are T-shaped and slightly curved ventrally.

FIG. 14.—Lateral view of pelvic girdle. (A) E. huicundo, QCAZ 14746, /. (B) E. ortizi, QCAZ 14779, /. (C) E. racemus, KU 168948, /. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Scale bars 5 2 mm.

ELEUTHERODACTYLUS OBMUTESCENS (KU 144090) CRANIAL OSTEOLOGY The skull (Figs. 3B, 4B, 5B) of Eleutherodactylus obmutescens is wider than long (lateral head length 90% head width at angles of jaw), and with a maximum height that is about 52% of its lateral length. Snout–vent length and cranial measurements and proportions are given in Tables 1 and 2. Endocranium Sphenethmoids.—The anteromedial margin of the sphenethmoid lies about 2/3 the distance from the anterior margin of the frontoparietal fontanelle to the end of the snout. The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous (Fig. 5B).

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157

FIG. 15.—Hand of species of the Eleutherodactylus orcesi Group. (A) Dorsal view of hand of Eleutherodactylus huicundo, QCAZ 14746, /. (B) ventral view of hand of E. ortizi, QCAZ 14779, /. (C) ventral view of prepollex of E. simoteriscus, ICN 22837, /. (D) ventral view of prepollex of E. thymelensis, KU 117722, /. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Scale bars 5 1 mm.

Dermatocranium Frontoparietals.—The lamina perpendicularis forms the anterodorsal margin of the optic fenestra (Fig. 5B). Parasphenoid.—The parasphenoid (Fig. 4B) is as long as wide. The cultriform process is widest along its posterior two-thirds and narrows anteriorly; the cultriform process ventrally invests approximately 48% of the bony sphenethmoid, but does not reach the level of the neopalatines and the vomers anteriorly. The anterior terminus of the cultriform process is deeply serrated. The parasphenoid has an acuminate posteromedial process that is broadly separated from the posterior margin of the fused exoccipitals. Vomers.—The postchoanal process is short and about one-half the length of the prechoa-

nal process. The left dentigerous process bears one teeth, whereas the right process bears three (Fig. 4B). Premaxillae.—The left premaxilla bears 10 teeth, whereas the right premaxilla bears eight (Fig. 4B). The posterolateral process of each premaxilla is triangular. Maxillae.—Each maxilla bears about 42 teeth (Fig. 4B). Neopalatines.—Each neopalatine bears a ventral triangular ridge that extends about one-fourth of its length (Fig. 4B). Suspensorium Squamosals.—In lateral view, the posterior margin of each ventral ramus is nearly straight (Fig. 5B).

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[No. 18

FIG. 16.—Foot of species of the Eleutherodactylus orcesi Group. (A) Dorsal view of foot of Eleutherodactylus huicundo, QCAZ 14746, /. (B) Ventral view of foot of E. thymelensis, KU 117722, /. (C) Ventral view of foot of E. ortizi, QCAZ 14779, /. (D) Ventral view of Element Y and prehallux of E. simoteriscus, ICN 22837, /. (E) Ventral view of Element Y and prehallux of E. simoterus, ICN 18821, /. Stippling denotes ossification; gray denotes cartilage; stippling on gray denotes mineralization. Scale bars 5 1 mm.

Hyobranchial Apparatus The hyoid apparatus was destroyed in the clearing and double-staining process, and therefore could not be examined for this study.

POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS OBMUTESCENS Axial system.—Presacrals I and II are partially fused dorsomedially (Fig. 17). In

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159

FIG. 17.—Dorsal view of Presacrals I–III of Eleutherodactylus obmutescens, KU 144090, /. Note partial fusion of Presacrals I and II. Gray denotes cartilage. Scale bar 5 2 mm.

dorsal view, the anterior margin of neural arches is anteriorly concave in Presacrals I, III–V, and VIII, and V-shaped in Presacrals VI–VII. The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > V ’ VIII > VI ’ VII > II. The orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral VIII, directed anterolaterally in Presacral II and III, and posterolaterally in Presacrals IV–VII. The urostyle is 98% the length of the presacral vertebral column. Pectoral girdle (Fig. 12B).—The maximum width of the cartilaginous sternum is about 70% its maximum length. The cartilaginous omosternum is wider than long (width 5 110% length). The glenoid end of the coracoid is about the same size as the sternal end. Pes.—The prehallux of the right foot has two elements, whereas the prehallux of the left foot has four elements (Fig. 18). The most proximal element is larger and relatively more ossified than the distal elements. When four elements are present, the distal-most element is minute and remains cartilaginous (Fig. 16A). ELEUTHERODACTYLUS ORCESI (KU 177814) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus orcesi (Figs. 3C, 4C, 5C) is slightly wider than

FIG. 18.—Prehallux of the left (A) and right (B) feet of Eleutherodactylus obmutescens, KU 144090, /. Note asymmetry in the number of elements. Gray denotes cartilage. Scale bar 5 1 mm.

long (lateral head length 96% head width at angles of jaw) and has a maximum height that is about 45% of its lateral head length (Fig. 5C). Snout–vent length and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—In dorsal view (Fig. 14C), the posteromedial margin of the sphenethmoid is posteriorly concave (Fig. 3C). The anteromedial margin of the sphenethmoid lies about 3/4 the distance from the anterior margin of the frontoparietal fontanelle to the end of the snout. In ventral view, the anterior terminus of the sphenethmoid is conspicuously triangular and reaches the level of the anterior margin of the vomers (Fig. 4C). The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous. Prootics and exoccipitals.—Each prootic forms the bony posterior and posterodorsal margins of the optic fenestra (Figs. 4C, 5C). In

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dorsal view, the posteromedial border of the fused exoccipitals, between the occipital condyles, has an angular shape (Fig. 3C). The posterolateral portion of each prootic almost articulates the otic ramus of the squamosal. Dermatocranium Frontoparietals.—The paired frontoparietals do not articulate with one another along the anterior two-thirds of the midline, but converge posteriorly to articulate (Fig. 3C). Ventrolaterally, each frontoparietal bears a lamina perpendicularis, which forms the anterodorsal margin of the optic fenestra (Fig. 5C). Parasphenoid.—The parasphenoid (Fig. 4C) has a maximum width that is equal to its length. Anteriorly, the cultriform process ventrally invests about 35% the length of the sphenethmoid, but does not reach the level of the neopalatines or the vomers. The anterior terminus of the cultriform process is slightly acuminate. The parasphenoid has a long, acuminate posteromedial process that is well separated from the posterior margin of the exoccipital. Vomers.—Each vomer (Fig. 4C) bears an elongate dentigerous process that extends posteromedially to a level only slightly anterior to the neopalatines. Teeth are not evident on the dentigerous processes. Premaxillae.—The left premaxilla bears nine teeth, whereas the right premaxilla bears eight. The dorsal portion of the alary process is as wide as its base. The posteromedial and posterolateral processes of the pars palatina are triangular, but the posteromedial process is narrower than the posterolateral process (Fig. 4C). Maxillae.—The pars dentalis of each maxilla bears approximately 47 teeth. The pars facialis of each maxilla has a low preorbital process that is not triangular (Fig. 5C). Laterally, the posterior terminus of the maxilla invests the anterior one-fourth of the quadratojugal. Suspensorium Squamosals.—The zygomatic ramus narrows anteroventrally, but unlike Eleutherodactylus huicundo, is relatively robust and conspicuous and terminates in a pointed tip (Fig. 5C).

[No. 18

Hyobranchial Apparatus The width of the hyoid plate is about 92% of its median length. The hyoid plate narrows anteriorly (Fig. 8B). The hyoglossal sinus is relatively narrow (Fig. 8B). The lengths of the posteromedial processes are about 115% of the midline length of the hyoid plate (Fig. 8B). The posterolateral processes are relatively short and curved (Fig. 8B). POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS ORCESI Axial system.—Presacral Vertebrae I and II are fused dorsomedially (Fig. 9B). In dorsal view, the anterior margin of the neural arches of each Presacral Vertebra is concave; this concavity is U-shaped in Presacrals I, III—VI, and V-shaped in Presacrals VII—VIII (Fig. 9B). The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > V ’ VI ’ VII > VIII > II. The urostyle is 112% the length of the presacral vertebral column. Pectoral girdle.—The sternum has a maximum width that is about two-thirds of its maximum length and is bifurcated posteromedially; the bifurcation extends through the posterior half of the sternum (Fig. 12C). The cartilaginous omosternum is slightly wider than long (width 5 106% length). The glenoid head of the coracoid is about the same size as the sternal head (Fig. 12C). ELEUTHERODACTYLUS ORTIZI (QCAZ 14779) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus ortizi (Figs. 3D, 4D, 5D) is wider than long (lateral head length 88% head width at angles of jaw) and has a maximum height that is about 39% of its lateral head length (Fig. 5D). Snout–vent length and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—In dorsal view, the posteromedial margin of the sphenethmoid is irregular and bears a conspicuous, midline process that extends well into the frontoparietal fontanelle (Fig. 3D). The anteromedial margin of the sphenethmoid lies about 60% the distance from the anterior margin of the frontoparietal fontanelle to the end of the

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snout. The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous (Fig. 5D). Dermatocranium Nasals.—In dorsal view (Fig. 3D), the anterior margin of each nasal is anteriorly convex. In lateral view (Fig. 5D), the maxillary process almost reaches the preorbital process of the maxilla. Frontoparietals.—Ventrolaterally, each frontoparietal bears a lamina perpendicularis that forms part of the anterodorsal margin of the optic fenestra (Fig. 5D). Parasphenoid.—The parasphenoid (Fig. 4D) has a width that is about 97% of its length. The cultriform process is widest in its posterior half and tapers slightly anteriorly. The cultriform process ventraly invests about 45% of the bony sphenethmoid, but does not reach the level of the neopalatines or the vomers anteriorly. The anterior terminus of the cultriform process is broad. The ventral surface of each parasphenoid ala has a low transverse ridge. Vomers.—The triangular prechoanal process of each vomer extends nearly to the level of the posterior margin of the posterolateral process of the premaxilla (Fig. 4D). The dentigerous process of each vomer bears one to three teeth and lies anterior to the cultriform process (Fig. 4D). Premaxillae.—Each premaxilla (Fig. 6B) bears nine teeth; the terminus of the alary process of each premaxilla has the shape of an inverted V. The lateral margin of each posterolateral process is concave (Fig. 4D). Maxillae.—Each maxilla bears about 45 teeth. The preorbital process of the pars facialis of the maxilla almost contacts the maxillary process of the nasal and has a nearly vertical posterior margin (Fig. 5D). Neopalatines.—Each neopalatine (Fig. 4D) is relatively long and invests about 35% of the ventrolateral surface of the sphenethmoid, via an acuminate process, which almost reaches the dentigerous process of the vomer. Hyobranchial Apparatus The hyoid apparatus was destroyed in the clearing and double-staining process, and therefore could not be examined for this study.

161

POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS ORTIZI Axial system.—Dorsal ossification of neural arches is not complete in Presacrals I and II (Fig. 9C). The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > V > VI ’ VII > II > VIII; the orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral III, VI, and VII, directed anterolaterally in Presacral II and VIII, and posterolaterally in Presacrals IV and V (Figs. 9C, 10). A calcified sesamoid lies on the anterolateral surface of the lateral margin of each sacral diapophysis; the sesamoid has a length of about two-thirds the width of the head of the sacral diapophyses (Fig. 9C). The urostyle is 107% the length of the presacral vertebral column. Dorsally, the urostyle bears a well-developed longitudinal ridge with two peaks, one anteriorly and the other posteriorly (Fig. 9C); the ridge decreases in height medially. Pectoral girdle.—The omosternum is long (width 5 67% length) and spade-shaped. The cartilaginous sternum was destroyed in the clearing and double-staining process and could not be examined. Pelvic girdle.—The medial margins of the ilia are U-shaped (Fig. 9C). Each ilial shaft is straight and lacks an evident longitudinal crest (Fig. 14B). The ilia are relatively robust compared to other species of the Eleutherodactylus orcesi Group (Fig. 9C). Pes.—The prehallux comprises three elements, being the distal element small and mineralized. Two minute calcified sesamoid elements lie ventral to Tarsal 1 (Fig. 16C). ELEUTHERODACTYLUS RACEMUS (KU 168948, 170158–61) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus racemus (Figs. 3E, 15E, 16E) is slightly wider than long (lateral head length 88–98% head width at angles of jaw). Snout–vent length and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—In dorsal view (Fig. 3E), the posteromedial margin of the sphenethmoid is posteriorly concave or sinuous. The anteromedial margin of the sphenethmoid lies

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[No. 18

about 40–58% the distance from the anterior margin of the frontoparietal fontanelle to the end of the snout. The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous (Fig. 5E). Dermatocranium Nasals.—In dorsal view, the anterior margin of each nasal is convex (Fig. 3E) or sinuous. In lateral view (Fig. 5E), the ventral margin of the maxillary process of each nasal is generally horizontal, irregular, and broadly separated from the preorbital process of the maxilla. Frontoparietals.—The frontoparietals are separated from each other (KU 168948, 170158; Fig. 3E) or articulate posteromedially (KU 170159–61). The relative size of the frontoparietal fenestra varies, but the fontanelle is always exposed. Low cranial crests are present in only one specimen (KU 170158), and are located in the posterolateral portion of the frontoparietals. The lamina perpendicularis is prominent and forms a minute part of the anterodorsal margin of the optic fenestra (Fig. 5E). Parasphenoid.—The parasphenoid is approximatly as wide as long (parasphenoid length 95.3–103.4% parasphenoid width). The cultriform process invests approximately 45–50% the length of the sphenethmoid and its anterior end lies posterior to the neopalatines and vomers (Fig. 4E). The anterior terminus of the cultriform process is variable in shape and can be highly acuminate, acuminate, or serrated (Fig. 19). The parasphenoid alae usually have a low transverse ridge (KU 170158–61; Figs. 19B, 19C) that is absent in one specimen (KU 168948; Figs. 4E, 19A). Vomers.—The postchoanal process is short and triangular (Fig. 4E). Each dentigerous process has 0–6 teeth. Variation on the number of teeth on each dentigerous process is shown in Table 3. Premaxillae.—Each premaxilla has 11–14 teeth. Variation on the number of teeth on each premaxilla is shown in Table 3. Maxillae.—Variation on the number of teeth on each maxilla is shown in Table 3. Neopalatines.—Medially, each neopalatine invests about 25–30% the length of the sphenethmoid (Fig. 4E).

FIG. 19.—Variation on shape of parasphenoid in adult females of Eleutherodactylus racemus. (A) Highly acuminate cultriform process, no longitudinal ridges on alae, KU 168948. (B) Acuminate cultriform process, low longitudinal ridges on alae, KU 170161. (C) Serrate cultriform process, low longitudinal ridges on alae, KU 170160. Scale bars 5 2 mm.

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TABLE 3.—Number of teeth on vomers, premaxillae, and maxillae of five adult females of Eleutherodactylus racemus.

KU 168948 KU 170158 KU 170159 KU 170160 KU 170161

Vomers (left, right)

Premaxillae (left, right)

Maxillae (left, right)

0, 5 5, 6 4, 4 3, 3 0, 0

12, 14 13, 13 12, 13 11, 13 11, 12

51, 56 68, 64 48, 52 52, 54 46, 45

Suspensorium Squamosals.—In lateral view (Fig. 5E), the posterior margin of each ventral ramus is nearly straight. The zygomatic ramus is relatively long compared to Eleutherodactylus huicundo (Figs. 5A, 5E). Hyobranchial Apparatus The width of the hyoid plate is about 80% of the midline length of this structure. The hyoglossal sinus is relatively narrow (Fig. 8C). The cartilaginous posterolateral processes are long and extend to a point posterior to the caudal margin of the hyoid plate (Fig. 8C). The posteromedial processes have a length that is about 180% of the median length of the hyoid plate. The proximal heads are slightly wider than the distal heads (Fig. 8C). POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS RACEMUS (KU 168948, 170158–61) Axial system.—The vertebral column is composed of seven (Fig. 9D) or eight presacral vertebrae (Table 4), the sacrum, and the urostyle. Dorsal ossification of neural arches of Presacral I is either complete (KU 170158– 59) or incomplete (KU 168948, 170160–61; Fig. 9D). Dorsomedially, Presacrals I and II are partially fused (KU 168948; Fig. 9D) or not fused (KU 170158–61). In dorsal view, the anterior margin of neural arches is usually anteriorly concave in Presacrals III–IV and usually V-shaped in Presacral I and Presacrals V–VIII (Fig. 9D). The relative lengths of the transverse processes and sacral diapophyses usually are: III > Sacrum > IV > V–VIII > II, but variation is high (Table 4). The orientation of the transverse processes usually is nearly perpendicular to the notochordal axis in Presacral III, VII, and VIII, directed ante-

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rolaterally in Presacral II, and posterolaterally in Presacrals IV–VI. (See variation in Table 4.) A calcified sesamoid lies on the lateral surface of the distal margin of each sacral diapophysis and has a length that is about two-thirds of the width of the head of the sacral diapophyses (Fig. 9D). The length of the urostyle is about 120% the length of the presacral vertebral column. Pectoral girdle.—The sternum is about 125% as wide as long and is always bifurcated posteriorly (Fig. 12D). The omosternum typically is arrow-shaped, but it can also be triangular or spade-shaped. The width of the omosternum is about 110% of its length. The glenoid head of the coracoid is slightly more expanded than the sternal head. Pelvic girdle.—Each ischium bears a prominent, anteriorly directed process at the level of ischium-ilium articulation (Fig. 14C). Pes.—The prehallux is composed of three elements; the two proximal elements are calcified and relatively large, whereas the distal element is minute and remains cartilaginous. ELEUTHERODACTYLUS SIMOTERISCUS (ICN 22837) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus simoteriscus (Figs. 3F, 4F, 5F) is slightly wider than long (lateral head length 95% head width at angles of jaw). SVL and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—In dorsal view (Fig. 3F), the posteromedial margin of the sphenethmoid is posteriorly concave. The anteromedial margin of the sphenethmoid lies about 2/3 the distance from the anterior margin of the frontoparietal fontanelle to the end of the snout. In ventral view (Fig. 4F), the anterior margin of the sphenethmoid reaches the level of the anterior fifth of the vomers. The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous (Fig. 5F). Dermatocranium Nasals.—In dorsal view (Fig. 3F), the anterior margin of each nasal is nearly straight. In lateral view (Fig. 5F), the ventral margin of

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[No. 18

TABLE 4.—Orientation and relative sizes of transverse processes of presacral vertebrae and sacrum of 15 adult females of Eleutherodactylus racemus. In individuals with seven presacral vertebrae, Presacral V, VI, and VII are not considered because of uncertain homology. KU no

No presacral vertebrae

Transverse processes relative length

168941

8

III > Sacrum > IV > V–VIII > II

168945

8

Sacrum > III > IV ’ V–VIII > II

168946

8

III ’ Sacrum > VIII > IV ’ VI ’ VII > II ’ V

168947

8

Sacrum > III > IV ’ VIII > V–VII > II

168948

7

III > Sacrum > IV > VIII > II

168949

7

III > Sacrum > IV > VIII > II

168950

8

III > Sacrum > IV > II ’ V–VII > VIII

168964

8

III > Sacrum > IV ’ VII–VIII > V–VI > II

168965

8

III > Sacrum > IV > VIII > II ’ V–VII

168966

8

III > Sacrum > IV > V–VIII > II

168968

8

III > Sacrum > IV > V–VIII > II

170158

8

III > Sacrum > IV > V ’ VII > VI > VIII > II

170159

8

III > Sacrum > IV > II ’ V–VIII

170160

8

III > Sacrum ’ IV > II > V–VIII

170161

8

III > Sacrum > II ’ IV ’ VIII > V–VII

the maxillary process of each nasal is approximately horizontal. Frontoparietals.—The frontoparietals articulate along most of their length and diverge only anteromedially, exposing the frontoparietal fontanelle (Fig. 3F). Parasphenoid.—The parasphenoid (Fig. 4F) is as wide as long and ventrally invests approximately 45% of the bony sphenethmoid,

Transverse processes orientation

Anterior: II, VIII Posterior: IV–VI Perpendicular: III, VII Anterior: II, VIII Posterior: IV–VI Perpendicular: III, VII Anterior: — Posterior: IV–VII Perpendicular: II, III, VIII Anterior: II Posterior: IV–V Perpendicular: III, VI–VIII Anterior: II Posterior: IV Perpendicular: III, VIII Anterior: II Posterior: IV Perpendicular: III, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VII Perpendicular: III, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VI Perpendicular: III, VII, VIII Anterior: II Posterior: IV–VII Perpendicular: III, VIII Anterior: II Posterior: IV–VII Perpendicular: III, VIII

but does not reach the level of the neopalatines or the vomers anteriorly. Each parasphenoid ala has a transverse ridge, which is low and difficult to see. The parasphenoid has a rounded posteromedial process that lies posterior to the posterior margin of the exoccipital. Vomers.—The postchoanal process is relatively short (Fig. 4F). Each dentigerous process bears three or four teeth.

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Premaxillae.—Each premaxilla bears 10 or 11 teeth. Neopalatines.—Each neopalatine ventrally invests about 30% of the ventrolateral surface of the sphenethmoid medially (Fig. 4F). Hyobranchial Apparatus The width of the hyoid plate is about 70% of its medial length (Fig. 8D). The hyoglossal sinus is relatively broad (Fig. 8D). Each hyale bears an anterior process that has a length about 80% of the median length of the hyoid plate. The hyoid plate does not present obvious mineralization. The posteromedial processes have a length that is about 107% of the median length of the hyoid plate. POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS SIMOTERISCUS Axial system.—The relative lengths of the transverse processes and sacral diapophyses are: III > IV > Sacrum ’ V > II ’ VI–VIII. The orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral III and VIII, directed anterolaterally in Presacral II, and posterolaterally in Presacrals IV–VII. The sacral diapophyses are not expanded distally. The urostyle is as long as the presacral vertebral column. Pectoral girdle.—The clavicles are robust (Fig. 12E); the distal head of each clavicle is about three times wider than the medial end. The glenoid head of each coracoid is as wide as the sternal head (Fig. 12E). The posterior portion of the suprascapula has some mineralization (Fig. 13). Manus.—The distal element of the prepollex has an approximately triangular shape (Fig. 15C). Pes.—The prehallux is composed of two calcified elements (Fig. 16D). The distal element is wider than the proximal element. ELEUTHERODACTYLUS SIMOTERUS (ICN 18821) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus simoterus (Figs. 3G, 4G, 5G) is slightly wider than long (lateral head length 91% head width at angles of jaw). Snout–vent length and cranial measurements and proportions are presented in Tables 1 and 2.

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Endocranium Sphenethmoids.—The sphenethmoid does not contribute to the anterior margin of the optic fenestra, which is cartilaginous (Fig. 5G). Dermatocranium Nasals.—In lateral view (Fig. 5G), the ventral margin of the maxillary process of each nasal is approximately straight. Parasphenoid.—The parasphenoid (Fig. 4G) is as wide as long and ventrally invests approximately 42% of the bony sphenethmoid. It lies posterior to the level of the neopalatines or the vomers. Each parasphenoid ala has a transverse ridge, which is low and difficult to see. The parasphenoid has a relatively short, acuminate posteromedial process that does not reach the posterior margin of the exoccipital. Vomers.—The dentigerous process does not reach the level of the anterior margin of the cultriform process of the parasphenoid (Fig. 4G). Each dentigerous process bears two teeth. Premaxillae.—Each premaxilla bears 11–13 teeth. Maxillae.—Each maxilla bears 51–53 teeth. Hyobranchial Apparatus The width of the hyoid plate is about 75% of its median length. Each hyale bears an anterior process that is about 70% the median length of the hyoid plate (Fig. 8E). The hyoglossal sinus is relatively broad (Fig. 8E). The posteromedial processes are long (about 130% of the median length of the hyoid plate) and slender. Each posteromedial process has a nearly straight lateral border (Fig. 8E). POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS SIMOTERUS Axial system.—The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > II ’ V–VIII. The orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral III and VIII, directed anterolaterally in Presacral II, and posterolaterally in Presacrals IV–VII. The urostyle is as long as the presacral vertebral column. Pectoral girdle.—The sternum is about 90% as wide as long. The posterior margin of the sternum is weakly bifurcated (Fig. 12F). The

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clavicles are moderately robust and the distal head of each clavicle is about four times wider than the medial end (Fig. 12F). The distal margin of the omosternum has a semicircular shape. Pes.—The prehallux is composed of three calcified elements; the two distal-most elements are partially fused in the left foot (Fig. 16E) and separated in the right foot. ELEUTHERODACTYLUS THYMELENSIS (KU 117722–23) CRANIAL OSTEOLOGY The ossified skull of Eleutherodactylus thymelensis (Figs. 3H, 4H, 5H) is slightly wider than long (lateral head length about 95% head width at angles of jaw). Snout–vent length and cranial measurements and proportions are presented in Tables 1 and 2. Endocranium Sphenethmoids.—In dorsal view, the posteromedial margin of the sphenethmoid is posteriorly concave (Fig. 3H) or sinuous. The anteromedial margin of the sphenethmoid lies about 60% the distance from the anterior margin of the frontoparietal fontanelle to the end of the snout. In ventral view (Fig. 4H), the anterior margin of the sphenethmoid almost reaches the level of the anterior margin of the vomers. The sphenethmoid does not contribute to the anterior margin of the optic fenestra (Fig. 5H), which is cartilaginous. Dermatocranium Nasals.—The nasals are relatively small compared to other species of the Eleutherodactylus orcesi Group (Fig. 3H). The anterior margin of the nasals is slightly sinuous or anteriorly convex (Fig. 3H). Frontoparietals.—In dorsal view (Fig. 3H), each supraorbital margin is slightly convex. Parasphenoid.—The parasphenoid (Fig. 4H) is as long as wide. The cultriform process is widest posteriorly, and tapers anteriorly, and ventrally invests about 50% of the sphenethmoid, but does not reach the level of the neopalatines or the vomers anteriorly. The anterior terminus of the cultriform process is serrate and acuminate. The posteromedial process is relatively short and does not reach the posterior margin of the exoccipital.

[No. 18

Vomers.—The triangular prechoanal process of the vomer has a serrate (Fig. 4H) or slightly serrate anterolateral margin. The dentigerous process bears two or three vomerine teeth. Premaxillae.—Each premaxilla has 8–10 pedicellate teeth. Maxillae.—Each maxilla has 38–40 teeth. Neopalatines.—Each neopalatine is relatively long and invests about 40% of the ventrolateral surface of the sphenethmoid medially via a slender acuminate tip, which almost reaches the dentigerous process of the vomer (Fig. 4H). Hyobranchial Apparatus The width of the hyoid plate is about 80– 90% of its median length. Each hyale bears an anterior process that is about 70–100% the median length of the hyoid plate (Fig. 8F). The posteromedial processes have a length that is about 120–135% the median length of the hyoid plate. POSTCRANIAL SKELETON OF ELEUTHERODACTYLUS THYMELENSIS Axial system.—Presacrals I and II are partially fused dorsomedially (Fig. 9E). The relative lengths of the transverse processes and sacral diapophyses are: III > Sacrum > IV > V > II > VI ’ VII ’ VIII. The orientation of the transverse processes is nearly perpendicular to the notochordal axis in Presacral III and VIII (Presacrals III and VII in KU 117723), directed anterolaterally in Presacral II (II and VIII in KU 117723), and posterolaterally in Presacrals IV–VII (IV–VI in KU 117723). In dorsal view (Fig. 9E), the anterior margin of neural arches is concave in all Presacral Vertebrae; this concavity is U-shaped in Presacrals I and III, and V-shaped in Presacrals IV–VIII (V-shaped only in Presacrals VI in KU 117723). The sesamoid length equals about three-fourths the width of the head of the sacral diapophyses. The urostyle is about 115% the length of the presacral vertebral column. Pectoral girdle.—The sternum has a maximum width that is about 50–65% its maximum length and is not bifurcated posteromedially (KU 117722; Fig. 12G) or is bifurcated along the posterior fifth (KU 117723). The cartilaginous omosternum is generally oval-shaped (Fig. 12G). The glenoid head of the coracoid is

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slightly less expanded than the sternal head (about the same size in KU 117723). Pelvic girdle.—In lateral view, the centrum of the acetabulum is mineralized. Manus.—The prepollex is elongate and composed of two calcified proximal elements and a minute, cartilaginous, distal element (Fig. 15D). Pes.—The prehallux is composed of two calcified proximal elements and one distal, minute, cartilaginous element (Fig. 16B). THE SHARED OSTEOLOGICAL CHARACTERS OF THE ELEUTHERODACTYLUS ORCESI SPECIES GROUP Species of the Eleutherodactylus orcesi Group share the characters presented below. The characters are based upon examination of adult females: (1) skull smooth, lateral head length 87.6–100% head width at angles of jaw; (2) maximum width of the skull at the posterior level of maxillae; (3) maxillae with 38–68 pedicellate teeth; (4) premaxillae narrowly separated from each other medially, each premaxilla with 8–14 teeth; (5) alary processes of premaxillae directed dorsally or posterodorsally and notched distally; (6) pars palatina of premaxillae with posterolateral and posteromedial processes; (7) nasals small, separated medially; (8) nasals not in contact with premaxillae, maxillae, or frontoparietals; (9) frontoparietals not articulated along anterior midline, exposing a large portion of frontoparietal fontanelle anteromedially; (10) cranial crests usually absent; (11) frontoparietals not fused with prootics; (12) epiotic eminences evident; (13) cristae paroticae long and narrow; (14) relative lengths of squamosal rami: ventral ramus > otic ramus > zygomatic ramus; (15) zygomatic ramus of squamosal not articulated with other bones of skull; (16) dentigerous process of each vomer oblique, slender, and broadly separated medially, with or without teeth (0–6), if teeth present, small; (17) neopalatines short to moderate-sized, slightly curved, expanded laterally, with ventral triangular ridge; (18) neopalatine and maxilla articulated, but a posterolateral gap in articulation is evident in ventral view; (19) ossified sphenethmoid partially subtending vomers; (20) sphenethmoid extended anteriorly, but not reaching the anterior border of

167

nasals; (21) parasphenoid T-shaped, width 85– 103% of length; (22) cultriform process of parasphenoid broad, narrowing anteriorly, ventrally investing 35–56% of sphenethmoid, not reaching level of neopalatines or vomers anteriorly; (23) parasphenoid alae posterolaterally projected at angle slightly greater than 908; (24) laterally, each parasphenoid ala reaching the level of, but lying posterior to, medial ramus of pterygoid; (25) parasphenoid with acuminate or rounded posteromedial process; (26) pterygoids slender, anterior rami not reaching neopalatines; (27) occipital condyles widely separated; (28) hyoid plate with posterolateral and posteromedial processes, anterolateral alary processes absent; (29) hyalia with long anterior processes; (30) posteromedial processes of hyoid plate wider at ends than at midshaft; (31) vertebral column composed of seven or eight free procoelous presacral vertebrae; (32) Presacral I with widely spaced cervical cotyles and two distinct articular surfaces (Type I; Lynch, 1971); (33) dorsally, Presacral II with process that articulates or almost articulates with Presacral I; (34) in most species, relative lengths of the transverse processes and sacral diapophyses: III > Sacrum > IV > V ’ VI ’ VII ’ VIII > II (but see Table 4); (35) orientation of the transverse processes variable (Table 4); (36) no neural spines evident; (37) sacrum with dorsal transverse ridge not extending to diapophyses, and bicondylar articulation with urostyle; (38) sacral diapophyses oriented posterolaterally and usually slightly expanded distally (but see E. simoteriscus); (39) lateral margins of the sacral diapophyses cartilaginous and overlying distal ends of ilial shafts (Type IIB articulation; Emerson, 1979); (40) calcified sesamoid on lateral surface of lateral margin of each sacral diapophysis; (41) urostyle with well-developed longitudinal ridge; (42) cartilaginous sternum usually bifurcated posteromedially (but can be entire in E. thymelensis; Fig. 12G); (43) omosternum oval-, triangular-, spade-, or arrow-shaped; (44) lateral end of clavicle broader than medial end and distinctly separated from the coracoid posteriorly; (45) anterior margin of coracoid conspicuously concave, posterior margin nearly straight; (46) suprascapula cartilaginous and slightly expanded distally, with two highly mineralized rami; (47) cleithrum elongated, well ossified;

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[No. 18

TABLE 5.—Species of Eleutherodactylus with an evident frontoparietal fontanelle exposed anteromedially. Subgenus, Species Series, and Species Groups are according to Lynch and Duellman (1997), except otherwise indicated. Species of the E. orcesi Group are not included. Specimens examined are listed in Appendix II. Species

E. altae E. auriculatoides E. discoidalis E. fraudator E. lynchi E. mercedesae E. nigriventris E. nyctophylax E. pluvicanorus E. pseudoacuminatus E. vicarius

Distribution

Subgenus, series, and group

Costa Rica and Panama´, 60–1245 m (Savage, 2002) Repu´blica Dominicana, 792–1890 m (Schwartz and Henderson, 1991) Argentina and Bolivia, 960–1550 m (Frost, 2002) Bolivia, 2050–2900 m (De la Riva and Lynch, 1997) Colombia, 2460–3150 m (Ruiz-Carranza et al., 1996) Bolivia, 1690–1950 m (Lynch and McDiarmid, 1987) Paranapiacaba and Borace´ia, Sa˜o Paulo, Brazil (Frost, 2002) Ecuador, 1140–2100 m (Lynch and Duellman, 1997) Bolivia, 2000–2300 m (De la Riva and Lynch, 1997) Ecuador and Colombia, 330–570 m (Ruiz-Carranza et al., 1996; Shreve, 1935) Colombia, 2900–3270 m (Ruiz-Carranza et al., 1996)

(48) each ilial shaft with low longitudinal crest and a dorsal protuberance; (49) ischium with short process at the point of articulation with ilium; (50) in lateral view, posterior margin of ischia posteriorly concave; (51) manus with six ossified carpal elements: ulnare, radiale, Carpal 2, Carpal 3-4-5, Element Y, and proximal prepollex (Morphology C; Fabrezi, 1992); (52) prepollex formed by two or three elements; (53) relative lengths of manual digits: IV > V > III > II; (54) phalangeal formula 2-2-3-3; (55) tarsal elements: tibiale, fibulare, distal tarsal 1, distal tarsal 2-3, Element Y, proximal prehallux; (55) tibiale and fibulare fused at distal ends; (56) prehallux composed of two to four elements; (57) calcified sesamoid element ventral to articulation between Metatarsals V and IV, and fibulare; (58) pedal phalangeal formula 2-2-3-4-3; (59) terminal phalanges of hands and feet T-shaped and slightly curved ventrally. DISTRIBUTION OF THE EXPOSED FRONTOPARIETAL FONTANELLE IN ELEUTHERODACTYLUS From a total of 127 species examined (Appendix II), excluding species of the Eleutherodactylus orcesi Group, I found eight

Eleutherodactylus: martinicensis: unistrigatus Eleutherodactylus: martinicensis: martinicensis Eleutherodactylus: conspicillatus: discoidalis Craugastor: —: — Eleutherodactylus: martinicensis: unistrigatus Eleutherodactylus: conspicillatus: — Eleutherodactylus: binotatus: lacteus Eleutherodactylus: martinicensis: unistrigatus Craugastor: —: — Eleutherodactylus: martinicensis: unistrigatus Eleutherodactylus: martinicensis: unistrigatus

species with large, exposed frontoparietal fontanelles (Table 5). Additionally, the presence of a large, exposed frontoparietal fontanella has been reported for E. fraudator and E. pluvicanorus (De la Riva and Lynch, 1997; Table 5) and E. mercedesae (Lynch and McDiarmid, 1987; Table 5). Species of Eleutherodactylus not examined in this study that lack a large exposed frontoparietal fontanelle include: E. librarius and E. ockendeni (Flores and Vigle, 1994); E. esmeraldas (Guayasamin, 2004); E. richmondi and E. planirostris (Lynch, 1971); E. cerastes, E. helonotus, and E. ingeri (Lynch, 1975); E. ruizi (Lynch, 1981b); E. dolops, E. mantipus, and E. nigrovittatus (Lynch, 1989); E. cryophilius, E. satagius, and E. xestus (Lynch, 1995); E. rhodopis, E. sartori, E. rostralis, and E. greggi (Lynch, 2000); E. carmelitae, E. insignitus, E. cristinae, E. delicatus, E. ruthveni, E. sanctaemartae, and E. tayrona (Lynch and Ruı´zCarranza, 1985). DISCUSSION INTRA- AND INTERSPECIFIC VARIATION IN THE ELEUTHERODACTYLUS ORCESI GROUP Intraspecific osteological variation is one of the most important but least studied aspects of

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FIG. 20.—Hypothesized closure pattern of the sternal bifurcation in species of the Eleutherodactylus orcesi Group.

anuran systematics (but see studies by Madej, 1965; Sanchiz, 1984; Trueb, 1977). Upon examination of adult females of the Eleutherodactylus orcesi Group, I found intraspecific variation of several characters that are worth mentioning: the frontoparietals can be separated or articulate posteromedially (E. racemus); the anterior terminus of cultriform process can be acuminate, highly acuminate, or serrate (E. racemus; Fig. 19); parasphenoid alae have or lack a transverse ridge (E. racemus; Fig. 19); the sternum can be entire or bifurcate (E. thymelensis); and Presacrals I and II are partially fused or separated (E. racemus). Additionally, the shape of certain bones and cartilages is variable among specimens of E. racemus. Some examples include the anterior border of nasals (anteriorly concave, convex, or sinuous), posterior border of the sphenethmoid (posteriorly concave or sinuous), anterior margin of neural arches (Uor V-shaped), orientation and relative size of the transverse processes of presacral vertebrae (Table 4), and omosternum (arrow-, spade-, or triangular-shaped). Because I used only adult females in this study, the variation noted above reflects natural polymorphisms and not sampling of different ontological stages. More problematic is the variation in number of presacral vertebrae in Eleutherodactylus racemus (7 or 8; Table 4). A reduction in the number of presacral vertebrae produces a problem of homology when comparing individuals or species with different numbers of vertebrae (summarized in Pu´gener, 2002). Based on the relative size and orientation of the transverse processes and using the criterion of similarity of position (Remane, 1956; in Wiley, 1981), it seems that Presacrals I–IV, VIII, and the sacrum are homologous in all specimens, meaning that the deleted vertebra would be Presacral V, VI, or VII. Three mechanisms can produce reduction in the

169

number of presacral vertebrae: (1) forward shift of the sacrum (Tihen, 1960, 1965; Lynch, 1978); (2) fusion of two vertebrae (see Trueb, 1973); and (3) mutation affecting segmentation genes early in development (see Pu´gener, 2002). The two first hypotheses imply a rearrangement of the same vertebral components—viz., presacral vertebrae, sacrum, and urostyle—present in a column with eight presacral vertebrae. Such a rearrangement should produce a distinct morphology. An example of such distinct morphology was provided by Lynch (1978); he argues that the presence of extra spinal nerve foramina on the urostyle in Batrachophrynus brachydactylus and Telmatobufo venustus, and the presence of short transverse processes on the urostyle in Telmatobufo venustus is evidence of a forward shift of the sacrum. In specimens of Eleutherodactylus racemus with a reduced number of presacral vertebrae, no change in the morphology of the axial system is evident (Fig. 9D); therefore, it is more probable that the deletion is the result of a mutation affecting segmentation genes. However, developmental studies are needed to test this hypothesis and to identify the individual vertebra that is deleted. The sternum is posteriorly bifurcated in species of the Eleutherodactylus orcesi Group (Fig. 12). This bifurcation varies among taxa and can be pronounced (e.g., E. orcesi; Fig. 12C), moderated (e.g., E. huicundo; Fig. 12A), weak (e.g., E. simoterus; Fig. 12F), or nonexisting (e.g., E. thymelensis; Fig. 12G). But, as noted above, E. thymelensis has intraspecific variation, suggesting that the bifurcated lobes of the sternum might fuse, late in ontogeny, in some species. The morphology of the sternum across species of the E. orcesi Group suggests that the closure of the bifurcation might have a posterior-anterior direction, rather than an anterior-posterior direction (Fig. 20). Intraspecific variation in tarsal and/or carpal elements has been reported for a few anuran taxa (Sanchiz, 1984; De la Riva, 1994). Fabrezi (2001) noted that variation in the number of elements of the prepollex and prehallux can be found even in the same specimen. I observed this kind of asymmetry in the elements that form the prehallux in Eleutherodactylus obmutescens (Fig. 18) and E. simoterus (Fig. 16E). These asymmetries could be explained

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by two equally parsimonious scenarios: (1) fusion of elements (thereby reducing apparent number of existing elements); or (2) failure of elements to divide (thereby never producing the greater number of elements). Ontogenetic studies are needed to distinguish between these hypotheses. The use of characters, such as those mentioned above, in systematic and phylogenetic studies can be misleading if intraspecific variation is unknown. Further studies should address intraspecific variation within and among populations, between sexes, and ontogenetically to improve confidence when using osteological characters to support systematic or phylogenetic hypotheses. Because few osteological descriptions are available for species of the genus Eleutherodactylus, it is difficult to discuss the phylogenetic significance of the characters shared among species of the E. orcesi Group (see Results); nevertheless, many characters seem to have a broad distribution in the genus and are included in the diagnosis for the genus Eleutherodactylus (Lynch, 1971:144–147). Herein, I comment on some characters not discussed by Lynch (1971). The general morphology of the iliosacral articulation in species of the E. orcesi Group corresponds to the Type IIB articulation described by Emerson (1979). In this type of articulation, the sacral diapophysis is directed posterolaterally and is not expanded (or only slightly expanded) distally, and the internal ligament is narrow and inserts on the dorsal surface of the diapophysis near its distal end. Several leptodactylids have this type of articulation, including E. punctariolus (Emerson, 1979) and E. esmeraldas (Guayasamin, 2004). Emerson (1979) suggested that Type IIB articulation should be distributed among frogs that use jumping as a locomotor mode; if this relationship is true, most species of Eleutherodactylus might have this articulation. The carpal morphology observed in the species of the Eleutherodactylus orcesi Group is widespread in anurans and includes six carpal elements (Morphology C; Fabrezi, 1992), a morphology that also has been recorded in E. esmeraldas (Guayasamin, 2004) and E. discoidalis (Fabrezi, 1992). The tarsal morphology of species of the E. orcesi Group is that described by Fabrezi (1993) for

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Leptodactylidae; this pattern of morphology is derived by having two free distal tarsals. The plesiomorphic tarsal morphology in anurans is: tibiale and fibulare fused distally; three free distal tarsals; Element Y; and prehallux (Fabrezi, 1993). In the E. orcesi Group, the prepollex is formed by two elements, except E. thymelensis (three elements), and the prehallux has two to four elements. A prepollex and prehallux each formed by two elements is the most generalized pattern of morphology in the anurans so far examined and has been hypothesized to be plesiomorphic (Fabrezi, 2001). Although Fabrezi (1992, 1993, 2001) provided a general pattern of the carpal and tarsal morphology of anurans, her studies include only one species of Eleutherodactylus. Further studies are necessary to determine the morphological diversity of the carpal and tarsal elements in the genus. MONOPHYLY AND DIAGNOSTIC DEFINITION OF THE ELEUTHERODACTYLUS ORCESI GROUP The frontoparietal fontanelle is exposed in juveniles of all leptodactylids, but this condition is retained in the adults of relatively few genera (Lynch, 1971). In the genus Eleutherodactylus, 19 species are known to have an exposed frontoparietal fontanelle in the adult (Table 5). The skulls of all the species of the Eleutherodactylus orcesi Group have a large portion of the frontoparietal fontanelle exposed anteromedially (Fig. 3). Although few species of Eleutherodactylus present this characteristic (Table 5), Lynch et al. (1996) stated that the exposure of the frontoparietal fontanelle in the E. orcesi Group probably was not a derived character. After examining C&S specimens of about 25% of the described species of Eleutherodactylus and using Hennig’s Auxiliary Principle, I hypothesize that the presence of an exposed frontoparietal fontanelle is homologous in species of the E. orcesi Group. I also suggest that the exposed frontoparietal fontanelle is a derived character with respect to the rest of Eleutherodactylus, supporting the monophyly of the E. orcesi Group. The other species of Eleutherodactylus that have a large frontoparietal fontanelle exposed (Table 5) are hypothesized to have acquired the character independently, except E. lynchi

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(discussed below). Differences between most species presented in Table 5 and species of the E. orcesi Group are evident. Eleutherodactylus altae has relatively larger nasals that are in medial contact, a parasphenoid that reaches the level of neopalatines anteriorly, and cartilaginous prepollex and prehallux. Eleutherodactylus auriculatoides has prominent dentigerous processes that are triangular in outline, numerous teeth in each dentigerous process (7–9), and a parasphenoid that reaches the level of neopalatines anteriorly. Eleutherodactylus discoidalis has dentigerous processes that are triangular in outline, an ossified sphenethmoid that does not subtend the vomers, and a parasphenoid that reaches the anterior border of the ossified sphenethmoid anteriorly. Eleutherodactylus fraudator has numerous teeth on each dentigerous process of the vomer, frontoparietals that extend conspicuously posterolaterally, relatively larger nasals, and a parasphenoid that reaches to the level of the neopalatines anteriorly (De la Riva and Lynch, 1997; their Fig. 5). Eleutherodactylus lynchi has an osteology similar to that of species of the E. orcesi Group, suggesting that it could be a close relative; nevertheless, I am not willing to include E. lynchi in the E. orcesi Group until we know more about the osteology of the species of the E. unistrigatus Group. Eleutherodactylus mercedesae has prominent dentigerous processes that are triangular in outline, each dentigerous process with numerous teeth (Lynch and McDiarmid, 1987; their Fig. 2B); no additional osteological characteristics are provided in the original description of this species. Eleutherodactylus nigriventris is in a clade diagnosed by the peculiar form of the inner margin of the vomer (Lynch, 2001); additionally, E. nigriventris has a neopalatine that partially subtends the dentigerous process of the vomer and a hyoid apparatus with anterolateral alary processes. Eleutherodactylus nyctophylax has larger nasals (Fig. 99 of E. palmeri in Lynch, 1971:147), prominent dentigerous processes that are triangular in outline, and a parasphenoid that reaches the anterior border of the ossified sphenethmoid anteriorly. Eleutherodactylus pluvicanorus has relatively larger nasals that are in median contact along their anterior halfs and vomers with prominent dentigerous processes that are nearly triangular in outline (De la Riva and

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Lynch, 1997). Eleutherodactylus pseudoacuminatus has relatively narrower dentigerous processes of the vomers, no vomerine teeth, and cartilaginous prepollex and prehallux. Eleutherodactylus vicarius has larger nasals and dentigerous processes that are triangular in outline. Additionally, Eleutherodactylus auriculatoides and E. nigriventris have disjunct distributions (Table 5) in relation to the species of the E. orcesi Group, making a close relationship unlikely. Characters shared among species of the E. orcesi Group are listed in Results; below, I provide a list of the characters that differ from the general pattern described for the genus (Lynch, 1971:144–147). The following characters are diagnostic for the E. orcesi Group, but should not be considered as synapomorphies until more is known about their distribution in the genus (numbers correspond to those in Results: The shared osteological characters of the Eleutherodactylus orcesi species Group): (1) skull smooth, lateral head length 87.6– 100% head width at angles of jaw; (7) nasals small, separated medially; (9) frontoparietals not in contact anteromedially, exposing a large portion of frontoparietal fontanelle; (16) dentigerous process of each vomer oblique, slender, and broadly separated medially, with or without teeth (0–6), if teeth present, small; (17) neopalatines short to moderate-sized, slightly curved, expanded laterally, with a ventral triangular ridge; (19) ossified sphenethmoid partially subtending vomers; (21) parasphenoid T-shaped, width 85–103% of its length; (22) cultriform process of parasphenoid broad, narrowing anteriorly, overlying 35–56% of sphenethmoid, not reaching the level of neopalatines and vomers anteriorly; (28) hyoid plate with posterolateral and posteromedial processes, anterolateral alary processes absent; (33) dorsally, Presacral II with process articulating or almost articulating with Presacral I; (42) cartilaginous sternum bifurcated posteromedially, but the sternum can be entire in E. thymelensis (see Results and Fig. 12G); (45) anterior margin of coracoid conspicuously concave, posterior margin nearly straight; (48) each ilial shaft with a dorsal protuberance and with low longitudinal crest (longitudinal crest absent in E. ortizi); and (50) posterior margin of ischia posteriorly concave in lateral view.

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Hennig (1966) characterized the essence of phylogenetic analysis as the search of the sister group. The phylogenetic relationships within the Eleutherodactylus orcesi Group are not addressed herein because we still don’t have a good understanding of the distribution of most osteological characters within Eleutherodactylus. Therefore, the selection of adequate outgroups is problematic. RESUMEN: El ge´nero Eleutherodactylus se encuentra distribuı´do en Sudame´rica, Centroame´rica y las Indias Occidentales, e incluye casi 700 especies descritas. La diversidad de Eleutherodactylus dificulta la realizacio´n de estudios que abarquen todas o la mayorı´a de sus especies. Como consecuencia, Eleutherodactylus ha sido histo´ricamente dividido en grupos fe´neticos infragene´ricos. Esta divisio´n se basa en la similitud entre especies y no es necesariamente congruente con grupos monofile´ticos dentro del ge´nero. Sin embargo, los grupos de especies se pueden considerar como hipo´tesis de grupos naturales (monofile´ticos). Este trabajo se enfoca en las ocho especies incluidas en el grupo Eleutherodactylus orcesi, el cual esta´ distribuı´do en los pa´ramos y bosques montanos de Colombia y Ecuador entre los 3000–4150 m. Los objetivos principales de este estudio son: (1) describir la osteologı´a de las especies en el grupo Eleutherodactylus orcesi, (2) diagnosticar el grupo en base a caracterı´sticas osteolo´gicas y (3) explorar si existen homologı´as que apoyen la monofilia del grupo de especies Eleutherodactylus orcesi. Para las descripciones osteolo´gicas, estudie´ especı´menes transparentados de las ocho especies incluı´das en el grupo. Para reducir los posibles efectos del dimorfismo sexual y heterocronı´a, revise´ u´nicamente hembras adultas. Para evaluar la validez de las posibles sinapomorfı´as del grupo de especies E. orcesi, examine´ especı´menes transparentados de 135 especies de Eleutherodactylus y obtuve informacio´n de la literatura para 29 especies adicionales. El cra´neo de todas las especies en el grupo E. orcesi tiene una considerable porcio´n de la fontanela frontaparietal expuesta entre los huesos frontaparietales y el esfenetmoides. Se hipotetiza que la presencia de esta fontanela es homo´loga en el grupo E. orcesi y que apoya la monofilia del grupo. Se discute la presencia de esta caracterı´stica en especies fuera del grupo E. orcesi y se hipotetiza que en estas especies la

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presencia de la fontanela es homopla´sica. Se diagnostica al grupo E. orcesi en base a caracteres osteolo´gicos y se discute la variacio´n de algunos de estos caracters en relacio´n al patro´n morfolo´gico descrito para el ge´nero Eleutherodactylus. Por u´ltimo, se discute la variacio´n intraespecı´fica de caracteres osteolo´gicos del cra´neo y postcra´neo de las especies en el grupo E. orcesi y, particularmente, de E. racemus. Acknowledgments.—I thank L. Trueb, J. D. Lynch, W. E. Duellman, E. O. Wiley, C. Sheil, L. A. Fitzgerald, E. Bonaccorso, O. Torres-Carvajal, H. Alamillo, E. Greenbaum, A. Pu´gener, J. B. Pramuk, and an anonymous reviewer for critically reviewing this manuscript and/or for comments during the elaboration of the study; L. Trueb and J. E. Simmons for facilitating access to the KU specimens; and L. A. Coloma and L. D. Lynch for granting loans from QCAZ and ICN, respectively. I am especially grateful to E. Bonaccorso for some of the figures (14F, 14G, 15F, 15G, 16F, 16G) presented in this work. Research was supported by The University of Kansas, the Fundacio´n para la Conservacio´n de Ecosistemas Amenazados (Numashir), and a fellowship from the Fundacio´n para la Ciencia y Tecnologı´a del Ecuador (FUNDACYT), under the sponsorship of the Departamento de Ciencias Biolo´gicas of the Pontificia Universidad Cato´lica del Ecuador.

LITERATURE CITED DE LA RIVA, I. 1994. A new aquatic frog of the genus Telmatobius (Anura: Leptodactylidae) from Bolivian cloud forests. Herpetologica 50:38–45. DE LA RIVA, I., AND J. D. LYNCH. 1997. New species of Eleutherodactylus from Bolivia (Amphibia: Leptodactylidae). Copeia 1997:151–157. DUELLMAN, W. E., AND L. TRUEB. 1986. Biology of Amphibians. McGraw-Hill, New York, U.S.A. EMERSON, S. B. 1979. The ilio-sacral articulation in frogs: form and function. Biological Journal of the Linnean Society 11:153–168. FABREZI, M. 1992. El carpo de los anuros. Alytes 10:1–29. ———. 1993. The anuran tarsus. Alytes 11:47–63. ———. 2001. A survey of prepollex and prehallux variation in anuran limbs. Zoological Journal of the Linnean Society 131:227–248. FLORES, G., AND G. O. VIGLE. 1994. A new species of Eleutherodactylus (Anura: Leptodactylidae) from the lowland rainforests of Amazonian Ecuador, with notes on the Eleutherodactylus frater assembly. Journal of Herpetology 28:416–424. FROST, D. R. 2002. Amphibian Species of the World: an online reference. V2.21 (15 July 2002). ,http:// research.amnh.org/herpetology/amphibia/index.html> (Reference: 01 April 2004). GUAYASAMIN, J. M. 2004. A new species of Eleutherodactylus (Anura: Leptodactylidae) from the northwestern lowlands of Ecuador. Herpetologica 60:103–116. GUAYASAMIN, J. M., D. ALMEIDA-REINOSO, AND F. NOGALES-SORNOSA. 2004. Two new species of frogs (Leptodactylidae: Eleutherodactylus) from the high

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Andes of northern Ecuador. Herpetological Monographs 18:127–141. HENNIG, W. 1966. Phylogenetic Systematics. University of Illinois Press, Urbana, USA. LYNCH, J. D. 1971. Evolutionary relationships, osteology, and zoogeography of leptodactylid frogs. Miscellaneous Publications, Natural History Museum, The University of Kansas 53:1–238. ———. 1975. A review of the broad-headed eleutherodactyline frogs of South America (Leptodactylidae). Occasional Papers, Natural History Museum, The University of Kansas 38:1–46. ———. 1978. A re-assessment of the telmatobiine leptodactylid frogs of Patago´nia. Occasional Papers, Natural History Museum, The University of Kansas 72:1–57. ———. 1981a. Leptodactylid frogs of the genus Eleutherodactylus in the Andes of northern Ecuador and adjacent Colombia. Miscellaneous Publications of the Museum of Natural History, University of Kansas 72: 1–46. ———. 1981b. The systematic status of Amblyphrynus ingeri (Amphibia: Leptodactylidae) with the description of an allied species in western Colombia. Caldasia 13:313–332. ———. 1986. The identification of the Middle American clade of Eleutherodactylus based on jaw musculature (Amphibia: Leptodactylidae). Herpetologica 42: 248–258. ———. 1989. Intrageneric relationships of mainland Eleutherodactylus (Leptodactylidae). I. A review of the frogs assigned to the Eleutherodactylus discoidalis species group. Contributions in Biology and Geology, Milwaukee Public Museum 79:1–25. ———. 1992. Two new species of Eleutherodactylus sulcatus from southwestern Colombia and the proposal of a new species group (Amphibia: Leptodactylidae). Journal of Herpetology 26:53–59. ———. 1995. Three new species of Eleutherodactylus (Amphibia: Leptodactylidae) from paramos of the Cordillera Occidental of Colombia. Journal of Herpetology 29:513–521. ———. 1997. Ranas pequen˜as, la geometrı´a de evolucio´n, y la especiacio´n en los Andes colombianos. Revista de la Academia Colombiana de Ciencias Exactas, Fı´sicas y Naturales 23:143–159. ———. 1999. Intrageneric relationships of mainland Eleutherodactylus: (Leptodactylidae). II. A review of the Eleutherodactylus sulcatus group. Revista de la Academia Colombiana de Ciencias Exactas, Fı´sicas y Naturales 21:353–372. ———. 2000. The relationships of an ensemble of Guatemalan and Mexican frogs (Eleutherodactylus: Leptodactylidae: Amphibia). Revista de la Academia Colombiana de Ciencias Exactas, Fı´sicas y Naturales 24:129–156. ———. 2001. Four osteological synapomorphies within Eleutherodactylus: (Amphibia: Leptodactylidae) and their bearing on subgeneric classifications. Revista de la Academia Colombiana de Ciencias Exactas, Fı´sicas y Naturales 25:127–136. LYNCH, J. D., AND W. E. DUELLMAN. 1997. Frogs of the genus Eleutherodactylus (Anura: Leptodactylidae) in western Ecuador: systematics, ecology, and biogeogra-

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APPENDIX I Alcohol-Preserved Specimens Examined (X-rayed) Eleutherodactylus racemus (KU 168941, 168945–47, 168949–50, 168964–66, 168968).

APPENDIX II Cleared-and-Stained Specimens Examined Eleutherodactylus achatinus (KU 288942). Eleutherodactylus actites (KU 288916). Eleutherodactylus acuminatus (KU 148720). Eleutherodactylus alcoae (KU 266022). Eleutherodactylus altae (KU 114769). Eleutherodactylus altamazonicus (KU 108982). Eleutherodactylus andi (KU 28255). Eleutherodactylus angelicus (KU 65797). Eleutherodactylus anotis (KU 132613). Eleutherodactylus antillensis (KU 45631). Eleutherodactylus appendiculatus (KU 166264). Eleutherodactylus armstrongi (KU 266359). Eleutherodactylus atkinsi (KU 203369). Eleutherodactylus atratus (KU 202307). Eleutherodactylus auriculatoides (KU 279103). Eleutherodactylus bakeri (KU 276275). Eleutherodactylus barlagnei (KU 221426). Eleutherodactylus baryecuus (KU 202315). Eleutherodactylus bogotensis (KU 110408–09). Eleutherodactylus boulengeri (KU 169055). Eleutherodactylus bransfordii (KU 113696). Eleutherodactylus brevirostris (KU 276329). Eleutherodactylus bromeliaceus (KU 146975). Eleutherodactylus buckleyi (KU 170125). Eleutherodactylus bufoniformis (KU 107102). Eleutherodactylus cajamarcensis (KU 120023). Eleutherodactylus calcarulatus (KU 120278). Eleutherodactylus caryophyllaceus (KU 113957). Eleutherodactylus celator (KU 177684). Eleutherodactylus cerasinus (KU 172285). Eleutherodactylus chloronotus (KU 170129). Eleutherodactylus caprifer (KU 177680). Eleutherodactylus cochranae (KU 279104). Eleutherodactylus colodactylus (KU 142155). Eleutherodactylus conspicillatus (KU 148827). Eleutherodactylus coqui (KU 79947). Eleutherodactylus crassidigitus (KU 114607). Eleutherodactylus cremnobates (KU 166290). Eleutherodactylus croceoinguinis (KU 119530). Eleutherodactylus crucifer (KU 120144). Eleutherodactylus crenunguis (KU 165226). Eleutherodactylus cruentus (KU 103016). Eleutherodactylus cuneatus (KU 203379). Eleutherodactylus curtipes (KU 288976, 288980). Eleutherodactylus cruralis (KU 173232). Eleutherodactylus danae (KU 164061). Eleutherodactylus devillei (KU 166269). Eleutherodactylus diadematus (KU 126147). Eleutherodactylus diastema (KU 31634). Eleutherodactylus discoidalis (KU 206433). Eleutherodactylus duellmani (KU 179283). Eleutherodactylus erythropleura (KU 170131). Eleutherodactylus elassodiscus (KU 168013). Eleutherodactylus escoces (KU 103006). Eleutherodactylus fenes-

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tratus (KU 175097). Eleutherodactylus fitzingeri (KU 107148). Eleutherodactylus fleischmanni (KU 68265). Eleutherodactylus gaigaeae (KU 114588). Eleutherodactylus glandulosus (KU 166275). Eleutherodactylus guentheri (KU 92819). Eleutherodactylus hectus (KU 200194). Eleutherodactylus huicundo (QCAZ 14746). Eleutherodactylus labiosus (KU 145000). Eleutherodactylus lancini (KU 129100). Eleutherodactylus lanthanites (KU 153018). Eleutherodactylus leoni (KU 189968). Eleutherodactylus leptophus (KU 170153). Eleutherodactylus leucopus (KU 189979). Eleutherodactylus longirostris (KU 166277). Eleutherodactylus luteolateralis (KU 165506). Eleutherodactylus loustes (KU 179245). Eleutherodactylus lynchi (KU 168383, 170140). Eleutherodactylus martiae (KU 126202). Eleutherodactylus megacephalus (KU 157702). Eleutherodactylus megalops (KU 170141). Eleutherodactylus melanostictus (KU 107943). Eleutherodactylus mexicanus (KU 71080). Eleutherodactylus minutus (KU 282823). Eleutherodactylus modipeplus (KU 142134). Eleutherodactylus monensis (KU 282891). Eleutherodactylus montanus (KU 283354). Eleutherodactylus myersi (KU 168440). Eleutherodactylus nasutus (KU 92822). Eleutherodactylus necerus (KU 165541). Eleutherodactylus nicefori (KU 168445). Eleutherodactylus nigriventris (KU 92737, 92739). Eleutherodactylus nitidus (KU 102657). Eleutherodactylus noblei (KU 108575). Eleutherodactylus nubicola (KU 124251). Eleutherodactylus nychtophylax (KU 165547). Eleutherodactylus obmutescens (KU 144090). Eleutherodactylus ockendeni (KU 123784). Eleutherodactylus ocreatus (KU 218508). Eleutherodactylus occidentalis (KU 62261). Eleutherodactylus octavioi (KU 92828). Eleutherodactylus orcesi (KU 177814). Eleutherodactylus orestes (KU 165552). Eleutherodactylus ornatissimus (KU 141969). Eleutherodactylus ortizi (QCAZ 14779). Eleutherodactylus parvillus (KU 111374). Eleutherodactylus parvus (KU 92834). Eleutherodactylus peraticus (KU 170162). Eleutherodactylus philipi (KU 202595). Eleutherodactylus phoxocephalus (KU 288926). Eleutherodactylus percultus (KU 166057). Eleutherodactylus platydactylus (KU 175090). Eleutherodactylus prolatus (KU 146163). Eleutherodactylus proserpens (KU 147046). Eleutherodactylus pseudoacuminatus (KU 123569). Eleutherodactylus pycnodermis (KU 202454). Eleutherodactylus quaquaversus (KU 166281). Eleutherodactylus quinquagesimus (KU 166281). Eleutherodactylus racemus (KU 168948, 170158–61). Eleutherodactylus rhabdolaemus (KU 173492, 175086). Eleutherodactylus riveti (KU 119857). Eleutherodactylus roseus (KU 168556). Eleutherodactylus rubicundus (KU 177452). Eleutherodactylus simoteriscus (ICN 22837). Eleutherodactylus simoterus (ICN 18821). Eleutherodactylus spinosus (KU 174530). Eleutherodactylus sulcatus (KU 123586). Eleutherodactylus surdus (KU 109077). Eleutherodactylus tenebrionis (KU 179230). Eleutherodactylus thectopternus (KU 150725). Eleutherodactylus thymelensis (KU 117722–23). Eleutherodactylus toftae (KU 209176). Eleutherodactylus trepidotus (KU 143436). Eleutherodactylus unistrigatus (KU 170149). Eleutherodactylus ventrimarmoratus (KU 119810). Eleutherodactylus versicolor (KU 119948). Eleutherodactylus vertebralis (KU 288929, 288932). Eleutherodactylus vicarius (KU 170155). Eleutherodactylus vidua (KU 165651). Eleutherodactylus walkeri (KU 178012). Eleutherodactylus w-nigrum (KU 288934).