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i11ustratedfrom specimens reared from eggs of the subsocial spider species Anelosimus studiosus and A. jabaquara respectively. They mainly differentiate ...
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Zootaxa 1162: 45-52 (2006) www.mapress.com/zootaxaJ

Copyright @ 2006 Magnolia Press

ISSN 1175-5326

(print edition)

ZOOTAXA ISSN 1175-5334 (online edition)

Two new species of Baeus (Hymenoptera: Scelionidae) from Southeastern Brazil parasitoids of Anelosimus (Araneae: Theridiidae) CECILIA B. MARGARÍAl, MARTA S. LOIÁCONO1 & MARCELO O. GONZAGN DivisiónEntomología,Museode La Plata,PaseodelBosques/n, 1900,La Plata,Argentina. E-mail:[email protected];[email protected] 2

Departamento de Zoologia, lB, Unicamp, Campinas, Silo Paulo, Brazil. E-mail: [email protected]

Abstraet Two new species, Baeus anelosimus sp. nov. and Baeus jabaquara sp. nov., are described and i11ustratedfrom specimens reared from eggs of the subsocial spider species Anelosimus studiosus and A. jabaquara respectively. They mainly differentiate based on habitus, body color, pilosity, antennal morphology, and wing venation. An identification key isprovided. Key words: Baeus, parasitoids, spiders, egg sacs, Anelosimus

Introduetion The genera Apobaeus, Baeus, ldris and Odontacolus (Scelioninae: Baeini), include species that develop as primary, solitary, endoparasitoids of spider eggs. Baeus, with worldwide distribution conteins 25 species (Johnson 2004). The genus is represented by five species in the Neotropical region and two in the Andean region, according to the new biogeographit scheme (Morrone 2001), all of them associated with spiders of the families Araneidae and Theridiidae (Brethes 1913; Dozier 1931; Girault 1915; Ogloblin 1957; Loiácono 1973; Loiácono & Margaria 2004). However, the fauna of the neotropics remains poorly known. The first Brazilian species, for example, was not described until 2004 (Loiácono & Margaria 2004).

1

This is the first known record of Baeus parasitizing eggs of Anelosimus

Simon

(Theridiidae). Females of Anelosimus take care of their egg sacs until the emergence of the .

spiderlings (e.g. Nentwig & Christenson 1986; Ito & Shinkai 1993; Furey 1998; Marques et al. 1998) (Fig. 1). The presence of Baeus in egg sacs of these spiders indicates that the

Accipted by M. Buffington: lO Feb. 2006; published: 30 Mar. 2006

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maternal care is probably not effective against the attack of egg parasitoids. In fact, a high incidence of parasitism by Baeus was previously reported for another theridiid species with maternal care, Theridion grallator Simon, from Hawaii (Gillespie 1990). According to Austin (1985) the egg sac wall and the presence of a guarding female appear to result in a high level of protection against opportunistic scavenging predators, but specialized parasitoids of eggs show a seriesof adaptations (such as small size, burrowing behavior) which allow them to escape from detection.

FIGURE 1. Female of Anelosimus sp. (O. P.-Cambridge) protecting.an egg saco

Methods

Egg sacs of A. studiosus and A. jabaquara were collected on Serra do Japi, a protected subtropical humid forest located in Jundiaí (23°11'S, 46°52'W), state of SiloPaulo, Brazil. Both hosts are subsocial spiders with extended maternal care (see Brach 1977, Furey 1998, Marques et al. 1998, Gonzaga & Vasconcellos-Neto 2001, 2002a, b). Terminology for morphological features are those proposed by Masner and Denis

(1996).Abbreviationsusedin thetextinclude:antennalsegments(A1.">,lateral-ocelar line (LOL), ocular-ocelar line (OOL), posterior-ocelar line (POL), sternite (S), tergite (T). Measurements are used for body length; relativeproportions were used for other measurements. Holotypes were deposited at the Museu do Zoologia da Universidade de Silo Paulo (MZUSP), and allotype and paratypes at the Museo de La Plata (MLP) entomological collections.

Bo:eusanelosimus Margaría and Loiácono, n. sp. (Figs. 2-6). Diagnosis Female body yellow ochraceous; antennal club longer than A2-A6with visible segments. Male body color chestnut brown, metasoma lighter and appendages yellowish, 46



Description Holotype female (Figs. 2-3) Color. Body and appendages yellow ochraceous. Body. Length 0.66 mm (Fig. 2). Head in dorsal view transverse (32:29), wider than mesosoma (32:20); vertex and frons with very short pilosity, and polygonal sculpture; head in lateral view higher than long (15:12), slightly higher than mesosoma; eye height: malar space (11:10); LOL:POL:OOL (10:13:1); head in frontal view subcircular, wider than high (29:19); eye with scattered very short pilosity; eye height:interorbital space (11:15). Antenna (Fig. 3). Antennal segments in the following relative proportions (46:11), (22:12), (S:7), (3:7), (5:7), (5:9), (13:20), (9:26), (7:25), (S:21), (9:13), antennal club longer than A2-A6(46:43). Mesosoma. In dorsal view with fine polygonal sculpture, wider than long (1S:12); mesoescutumtransverse (1S:lO); scutellum and metanotum stripe like; mesonotum with short semidecumbent pilosity. Metasoma. In dorsal view with T2(first visible tergite) wider than long (27:1S); T3- T6 wider than long (25: 19); T 7 triangular. S[ with short longitudinal crenulae.

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Allotype male (Figs. 4-6) Color. Body light chesthut brown, metasoma lighter than remaining parts of body, and appendages yellowish. Body. Length 0.9 mm. Head in dorsal view transverse(24:1S); eye height:malar space (S:7), LOL:POL:OOL (6:13:2); head in frontal view wider than high (25:16); eyes with very short pilosity; eye height:interorbital space (10:16); mandibles with three teeth (Fig. 4). Antenna. (Fig. 5). Antennal segments in the following relative proportions: (36:15), (1S:11), (12:12), (5:10), (5:10), (5:11), (6:11), (6:13), (7:14), (4:21), (13:16), (17:16). Mesosoma. In lateral view higher than long (24:20). Wings. Fore wings hyaline, relatively narrow, length:wide (70:19), apically rounded, overlapping the apex of metasoma; stigmal vein as in Fig. 6; hind wings hyaline with setae slightly longer than wing width. Metasoma. Metasoma in dorsal view longer than high, with first tergite trapezoidal, wider than long (13:4), with longitudinal costae; T2wider than long (21:10), with costae in the posterior portion of the segment. Genitalia. Digitus with three small teeth, penis valves and ventral portion of aedeagalvolsellar shaft without sclerotization; volsellar laminae developed as a weakly ventral ,; TWO NEW BAEUS

@ 2006 Magnolia Press

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ZOOTAXA

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plate; aedeagallobe and aedeago-volsellar shaft combined near to two times length of basal segment. 5

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Mesosoma. In dorsal view with setigerous puncture sculpture, as wide as long (15:12); mesoescutum transverse (15:7); scutellum and metanotum narrow stripe like; mesonotum with conspicuous semidecumbent pilosity.

Metasoma. T2 (first visible tergite) wider than long (26: 15) and conspicuous pilosity; T3- T6 wider than long (15:10); T7 triangular. SI with short longitudinal crenulae.

Allotype male (Figs. 9-11). Color. Body walnut brown, metasoma lighter, and appendages yellowish. Body. Length close to 0.8 mm, eye height:malar space (9:8), LOL:POL:OOL (7:14:1); head in frontal view wider than high (26:18); eyes with scattered very short pilosity; eye height:interorbital space (9:21). Antenna. (Fig. 9). Antennal segments in the following relative proportions: (40:15), (22:10), (10:10), (7:11), (8:13), (8:10), (8:11), (10:12), (7:13), (11:11), (11:13), (16:10). Mesosoma. In lateral view longer than high (33:20). Wings. Fore wings hyaline narrow, length:width (55:18), apically rounded, overlapping the apex of metasoma, stigmal vein (Fig. 10); venation and wing darker than in B. anelosimus;hind wings hyaline, with setae longer than wing width. Metasoma. Metasoma with first tergite trapezoidal wider than long (14:4), with longitudinal costae in all segment surface; T2 wider than long (23:14), with costae in the anterior portion of the segment surface. Genitalia. (Fig. 11). Digitus with three very small teeth, penis valves and ventral portion of aedeago-volsellar weak1ysclerotized; volsellar laminae developed as a weakly ventral plate; relative length between aedeagal lobe, and aedeagal-volsellar shaft and basal segment (34:53). VariabiUty Body completely

yellow, or yellow with castaneus

dorsal surface.

Type material designation Holotype female (on card), Brazil, Jundiaí, State of Sao Paulo, Serra do Japi, 20-III2005, Gonzaga coll., reared from Anelosimus jabaquara (Araneae: Theridiidae) eggs. Allotype male (on microscopic slide), same data as holotype. Paratypes females (5), (4 on cards, 1 on microscopic slide), same data as holotype.

Distribution Baeus jabaquara sp. nov. is distributed in the Brazilian state of Sao Paulo. This area corresponds to Paraná subregion of the Neotropical region, according to the new biogeographical scheme ofMorrone (2001).

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@ 2006 Magnolia Press

MARGARÍA

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Etymology This species is named after the epithet of the spider host Anelosimus jabaquara used as noun in apposition.

Key to Neotropical species ofBaeus 1. Body color black '~ \

1'. Body color yellow, yellow-ochraceous 2.

2

;

or walnut

3

Head and tarsi dull honey yellow. Al < A3-A6, male black with antenna and legs

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(except coxae) yellow

Baeus auraticepsGirault

2'. Head black, first coxae walnut brown, second and third coxae brownish yellow, antennal club yellowish, Al>A3-A6,male with legs yellowish Baeus achaearaneus Loiácono 3. Antennal club> 2 times longer than wide 3'. Antennal club < 2 times longer than wide 4.

4 5

Antennal club 2.91 times longer than wide. Body color walnut, antennae, trochanters,

apex oftibiae and first four tarsomeres lighter Baeus platensis (Brethes) 4'. Antennal club 2.14 times longer than wide. Body color walnut brown, antennae and 5.

legs yellowish Baeus metazygiae Loiácono et Margaría Head 1.79 times wider than mesosoma. Body and appendages yellow, with conspicuous pilosity. Al 1.33 times longer than wide. Antennal club compact with traces of segmentation, 1.4 times longer than wide .......................................................................

, Baeusjabaquara Margaría et Loiácono sp. nov. 5'. Head < 1.79 times wider than mesosoma. Body color walnut to yellow ochraceous, with normal pilosity. Antennal club 1.70 to 2.30 times longer than wide 6

6. Antennal club: Al-A61.80 times longer than wide. Antennal club subcompact; ~ 1.83 times longer than wide. Head 1.60 times wider than mesosoma. Body and appendages yellow ochraceous. Baeus anelosimus Margaríaet Loiácono sp. nov. 6'. Antennal club: Al-A6 1.24 times longer than wide; antennal club compacto Head 1.22 times wider than mesosoma. Head, thorax and vertex walnut brown; antennal club and I

legs cinnamon buff to cinnamon and ochraceous tawny

Baeus latrodecti Dozier

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Acknowledgments

Financial support from the Secretaría de Ciencia y Técnica de la Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina), and Funda