Coleoptera: Scarabaeoidea: Passalidae: Passalinae ...

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Instituto de Ecología, A.C, Xalapa, Veracruz, Mexico. Abstract. Keywords. Bess beetles, cloud forest, Mountain. Mesoamerican pattern, Tehuantepec. Isthmus.
Neotrop Entomol https://doi.org/10.1007/s13744-018-0619-2

SYSTEMATICS, MORPHOLOGY AND PHYSIOLOGY

A New Species of Vindex Kaup (Coleoptera: Scarabaeoidea: Passalidae: Passalinae: Proculini) from Oaxaca, Mexico ER ARIZA-MARÍN , P REYES-CASTILLO, V MOCTEZUMA, JL SÁNCHEZ-HUERTA Instituto de Ecología, A.C, Xalapa, Veracruz, Mexico

Keywords Bess beetles, cloud forest, Mountain Mesoamerican pattern, Tehuantepec Isthmus Correspondence E.R. Ariza-Marín, Instituto de Ecología, A.C, Carretera antigua a Coatepec 351, El Haya, 91070 Xalapa, Veracruz, Mexico; erarizam@ unal.edu.co Edited by Takumasa Kondo – CORPOICA Received 20 March 2018 and accepted 26 June 2018

Abstract Vindex chimalapensis Ariza-Marín, Reyes-Castillo, Moctezuma & SánchezHuerta, a new species, is described from the cloud forest in Oaxaca, México. Vindex chimalapensis is like V. sculptilis Bates in the form of lateral elytral punctures and glabrous epipleura, but has dorsal punctures in the pronotum and the form of the aedeagus differs on the basal piece. Male genitalia, female genitalia, and head are shown in photographs. Vindex chimalapensis is the only species known from this genus with dorsal punctures on the pronotum. Ecology, distribution, and biogeography of Vindex and the Mountain Mesoamerican distribution pattern are discussed, with emphasis on V. chimalapensis.

* Sociedade Entomológica do Brasil 2018

Introduction Vindex Kaup is a genus from mountain cloud forest of the Mexican Transition Zone (ZTM), which follows a Mountain Mesoamerican distribution pattern (Reyes-Castillo & Halffter 1978). Vindex has four valid species; two species are distributed to the east of Isthmus of Tehuantepec and the other two to the west from México to Guatemala and El Salvador (Hincks & Dibb 1935, Reyes-Castillo 2003). According to Boucher (2006), Vindex is a monophyletic genus, supported by two autapomorphies corresponding to female sexual characters. Recently, another new species was discovered from San Miguel Chimalapa, Oaxaca, Mexico, and is herein described.

Material and Methods Specimens of new species were compared with specimens of four species described. External morphological characters were examined using an LEICA EZ4HD microscope. Male and female genitalia were dissected for holotype and 10 paratypes, cutting surrounding tissues of the last tergal and

sterna abdominal segment; each genitalia was cleaned in a 10% KOH solution and then washed in 95% ethanol. The aedeagus was glued in a new label and placed in the pin of the corresponding specimen; female genitalia were placed into a genitalia vial with 95% ethanol. External morphology pictures were taken using a Leica Z16APOA stereomicroscope and the fabricant software (z-stack image capture method). Genitalia photographs were taken using a LEICA EZ4HD microscope. The right membranous wing was dissected for holotype and a female paratype. Pictures of paratype wing plectrum were taken with a Scanning Electron Microscope (JEOL JSM – 5600 LV). Measurements of body parts were taken with a digital caliper. The length of the body was measured from the mandible apex to elytra end. Type series will be deposited in the following collections: IEXA Colección entomológica del Instituto de Ecología, A. C. CNIN Colección Nacional de Insectos, Instituto de Biología, Universidad Nacional Autónoma de México UVGC Arthropod Collection, Universidad del Valle de Guatemala JLSHC Jose Luis Sánchez-Huerta Collection VMC Victor Moctezuma Collection

Ariza-Marín et al

Description of external morphology and aedeagus follows the nomenclature proposed by Reyes-Castillo (1970) and female genitalia by Boucher (2006). In this work, we follow the phylogenetic species concept (sensu Wheeler & Platnick 2000), because the species described is diagnosable by a unique combination of characters. Taxonomy Vindex chimalapensis Ariza-Marín, Reyes-Castillo, Moctezuma and Sánchez-Huerta, new species Description Holotype male Dimensions. Total length 21.75 mm; body thickness at the metacoxal level 3.78 mm; body thickness at medial part of mesothorax 3.46 mm; elytral length at midline level 12.82 mm; pronotal length at midline level 5.19 mm; pronotal width at lateral fossae level 6.91 mm; elytral width at metacoxal level7.39 mm. Habitus. Small-sized, macropterous, body flattened, shiny black. Head. Anterior border of labrum straight, labrum covered by setae evenly distributed. Clypeus flat directed downward. Fronto-clypeal suture interrupted by internal tubercles. External tubercles directed laterally at an acute angle, each with a sharp apex. Internal tubercles developed similar length than external tubercles. Frontal ridge “U” shape (in frontal view), emerging from base of central tubercle to internal tubercle apex. Frontal area smooth without punctures (Fig 1). Central tubercle small, with apex not free; posterolateral tubercles marked and transverse. Frontal fossae glabrous and rugose at apex. Post-frontal groove entire. Punctures behind supraocular keels. Eyes well developed; canthus glabrous; post-ocular groove wide, with four puncture lines. Antennal club with three short lamellae, basal lamellae as wide laterally as the length of the first three flagellomeres. Mandible apex tridentate, inner tooth reduced; internal inferior tooth bifid in left mandibles and simple in right mandibles. Hypostomal process glabrous, reaching the median part of mentum. Ligula tridentate. Maxilla with lacinia bidentate. Mentum anterior border bilobed in medial third, lateral scars pubescent, lateral margins straight. Thorax. Pronotum disc with dorsal punctures anteriorly and medially; marginal groove on anterior margin glabrous and oblique, length 2/3 of pronotum anterior border length; median groove well defined; lateral fossae well-defined and punctuated (20 punctures per side). Prosternum

Fig 1 Vindex chimalapensis sp. nov., head and pronotum.

posterolaterally pubescent below the dorsal marginal groove of the pronotum. Prosternellum pentagonal. Mesosternum glabrous; mesosternal scar matt, and deeper anteriorly. Posterior angles of mesoepisternum and mesoepimeron glabrous. Metasternal disc not delimited by punctures. Anterior-lateral area of metasternum pubescent; metasternal groove pubescent, narrower than medial portion of mesotibia, apex rounded. Elytra. Shiny, anterior border straight and sparsely pubescent at basal striae, short setae of approximately 0.5 mm; humeri and epipleura completely glabrous; striae with rectangular and marked punctures lateral view, and dorsal view rounded at the base of striae 1–3 in 1/10 of anterior part, striae and interstriae with the same width in dorsal view. Wings. Fully developed (Fig 2). Plectrum with pointed spines, distance between spines 3.9–6.4 um, spine width 2.3– 2.9 um, spine length 8.2–8.9 um (Fig 3). Legs. Anterior border of profemur with marked and complete grove, apical spur rounded; mesotibia with a spine laterally; meso- and metatibiae with long dorsal spur at the apex, the same or longer size than the first two tarsomeres.

Fig 2 Vindex chimalapensis sp.,membranous wing.

A New Species of Vindex from Oaxaca

Fig 3 Vindex chimalapensis sp. nov wing plectrum at X 2500 (A) and X 4000 (B); 10 um scale.

Abdomen. Last abdominal tergite with posterior marginal groove present medially, but not extending laterally, without punctures laterally. Aedeagus. Basal piece in ventral partially divided in “V” shape, completely separated from parameres; parameres separate medially and expanding from the center to the outside in ventral view, parameres in triangular shape with apex narrow in lateral view; median lobe twice as long as than tegmen (basal piece + parameres) in ventral view (Fig 4). Internal sac (endophallus) with pubescence in dorsal and ventral face (Fig 4A). Female Genitalia. Vagina with two proximal ventral lobes (lbpv), one dorsal proximal lobe (lbpd), two flattened and sclerotized medial dorsal lobes (lbmd) surrounding lbpd and two internal sclerotized plates between lbpv and lbpd (Fig 5). Paratype Variation. Lateral fossae of pronotum abundantly punctuated between 12 and 20 punctures on each side. Last abdominal sternite with or without some punctures in lateral margin. Paratype Dimensions (n = 16). Total length 19.98–22.14 mm; body thickness at the metacoxal level 3.73–4.06 mm; body

thickness at medial part of mesothorax 3.08–3.59 mm; elytral length at midline level 12.09–12.85 mm; pronotal length at midline level 4.85–5.27 mm; pronotal width at lateral fossae level 6.45–7.11 mm; elytral width at metacoxal level 6.93– 7.46 mm. All types of materials were measured. Derivatio Nominis. Adjective derived from the name of the region where type series was collected. Type Locality. MEXICO, Oaxaca, municipality of San Miguel Chimalapa, San Antonio. Specimens examined Holotype. ♂, “MEXICO, Oaxaca, San Antonio, San Miguel Chimalapa |16°39’44,5” N 94°13′14,6” W, 1550 msnm | Bosque de Niebla, CD Liquidambar | 3.v.2016, SánchezHuerta & Moctezuma.” Paratypes. 5♀♀, same data as holotype, 7♂♂ 2♀♀ dry specimens, 1♂ & 1♀ in ROH, with the same data except “vii.2017.” Type deposition. Holotype and 1 ♂♂, 3 ♀♀ and 1 ♂♂ dry specimens and 1♂ & 1♀ in ROH paratypes will be deposited in IEXA. Rest of paratypes as follows: CNIN (2 ♂♂, 1♀♀), UVGC (2 ♂♂, 1 ♀♀), JLSHC (1 ♂♂, 1 ♀♀), VMC (1 ♂♂, 1 ♀♀). Diagnosis

Fig 4 Vindex chimalapensis sp., aedeagus. A Ventral view. B Lateral view.

Vindex chimalapensis n. sp. differs from the other species of Vindex by having abundant punctures on pronotum and behind supraocular ridges (Fig 1). Vindex chimalapensis sp. nov. is similar to V. sculptilis Bates (1886) in shape of punctures of elytral striae, teeth in mandible apex, wing development and wide post-ocular groove. However, V. sculptilis can be differentiated by the following characters: mesoepimeron is pubescent; mesotibiae without spines; median lobe and tegmen of aedeagus have similar length; and vagina doesn’t have internal sclerotized plates between lbpv and lbpd.

Ariza-Marín et al

3.

3’

Fig 5 Vindex chimalapensis sp., female genitalia. A Dorsal view. B Ventral view. Ventral proximal lobe (lbpv), dorsal proximal lobe (lbpd), medial dorsal lobes (lbmd). Scale 1 mm.

4.

Distribution and ecology This species only occurs in Los Chimalapas region, the easternmost part of Oaxaca state, but it could be also located on the westernmost area of Chiapas. Vindex chimalapensis is a hygrophilous species that inhabits in conserved cloud forest near 1550 m alt. Type series was hand collected in galleries under rotten fallen logs cortex of the American sweetgum Liquidambar styraciflua L.

Identification key for species of the genus Vindex Kaup, 1871 1.

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2.

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Epipleura pubescent in the 1/10 basal. Lateral punctures of elytra rounded. Frontal fossae smooth. Meso- and metatibiae with short dorsal spur at the apex, the same size of the first tarsomere. Aedeagus round shape (median lobe similar as tegmen). Female genitalia with medial dorsal lobes globular ……………...…………...……….2 Epipleura glabrous. Lateral punctures of elytra elongated (oval or rectangular), Frontal fossae rugose. Meso- and metatibiae with long apical spur, the same or longer size than the first two tarsomeros. Aedeagus elongated shape (median lobe longer than tegmen). Female genitalia with medial dorsal lobes flattened …………………..............………….3 Wings well-developed. Eyes globular, canthus not extending past the lateral margin of the eye. Antennal club with three short lamellae, basal lamellae as wide laterally as the length of the first three flagellomeres (Mexico: Sierra Madre Oriental, Trans- Mexican Volcanic Belt & Oaxaca Mountain System) ………………… Vindex agnoscendus (Percheron, 1841) Wings reduced. Eyes reduced, canthus extending laterally beyond the lateral margin of the eye. Antennal club with three long lamellae, basal lamellae as wide laterally as the length of the first four flagellomeres. (Sierra

4’

Madre del Sur) …….……………………………….……………… …….….… Vindex gonzaloi Reyes-Castillo & Castillo, 1993 Elytra with dorsal punctures rounded. Wings well- developed. Eyes globular, canthus not extending past the lateral margin of the eye. Antennal club with three short lamellae, basal lamellae as wide laterally as the length of the first three flagellomeres …........…………...4 Elytral dorsal punctures elongated. Wings reduced. Eyes reduced, canthus extending laterally beyond the lateral margin of the eye. Antennal club with three long lamellae, basal lamellae as wide laterally as the length of the four flagellomeres (Mexico: Chiapas, & Guatemala) …………. ………………………………………. Vindex synelitris Gravely, 1918 Punctures on pronotum and behind supraocular ridges. Prosternellum pentagonal. Mesoepimeron pubescent. Mesotibiae with spine. Female genitalia with two internal sclerotized plates between lbpv and lbpd. Aedeagus with median lobe twice longer than tegmen (Mexico: Oaxaca) …..…………………...... Vindex chimalapensis n. sp. Pronotum and area behind supaocular ridges without punctures. Prosternellum narrowly rhomboidal. Mesoepimeron glabrous. Mesotibia without spines. Female genitalia without two internal sclerotized plates between lbpv and lbpd. Aedeagus with median lobe similar in length with tegmen (Mexico: Chiapas; Guatemala & El Salvador) ………………………….………………… ………………………….……………… Vindex sculptilis Bates, 1886

Discussion Vindex chimalapensis exhibit a character combination that conforms well to the genus Vindex, notwithstanding the fact that the new species is the only member in the genus which shows dorsal punctures in pronotum. Vindex chimalapensis seems to be closely related to V. sculptilis, but differences in external morphology and genitalia help to easily separate these species. We found that female genitalia pattern for Vindex proposed by Boucher (2006) only apply for species reviewed in that work (V. agnoscendus, V. gonzaloi and V. sp. Nicaragua). According to Boucher (2006) Vindex has a female genitalia pattern, consisting of two sclerotized proximal ventral lobes (lbpv), one dorsal proximal lobe (lbpd) and two globular mendian dorsal lobes (lbmd); which we did not find in V. chimalapensis and V. sculptilis. These species have a Xylopassaloides’ female genitalia pattern, and the median dorsal lobes are flattened. Phylogenetic studies are needed in order to confirm or refute the relationship betwen V. chimalapensis and V. sculptilis. This is the second study on Passalidae that describe the female genitalias; it seems to be taxonomically informative because clear differences in vagina sclerotization are shown between V. chimalapensis and V. sculptilis.

A New Species of Vindex from Oaxaca

Nevertheless, the use of female genitalia for species delimitation must be explored on different genera of Passalidae. The formerly known distribution of Vindex on the tropical mountains of the Mexican Transition Zone showed a disjunction at Tehuantepec Isthmus: V. agnoscendus (Percheron) from Sierra Madre Oriental, Trans-Mexican Volcanic Belt and Oaxaca Mountain System; V. gonzaloi Reyes-Castillo & Castillo, from Sierra Madre del Sur; V. sculptilis from the Chiapas Central Massif, Sierra Madre de Chiapas and the Central American Nucleus and V. synelytris Gravely from Sierra Madre de Chiapas and the Central American Nucleus. Vindex host specificity knowledge is not complete, but some associations have been reported: V. agnoscendus collected on Fagus mexicana Martínez, Pinus sp., Quercus sp.; V. gonzaloi on Pinus sp. (Reyes-Castillo 2003) and V. chimalapensis on L. styraciflua. The Proculini genera Heliscus, Odontotaenius, Oileus, Petrejoides, Proculus, Pseudacanthus, Verres and Veturius are also associated with L. styraciflua (Reyes-Castillo 2003). Vindex chimalapensis is only known from the type locality and apparently has a restricted and isolated distribution area, as occurs with diverse Scarabaeoidea species from Los Chimalapas (Moctezuma & Halffter 2017). The restricted distribution and hygrophylous habits of V. chimalapensis could indicate a high degree of susceptibility of this species to habitat transformation. Los Chimalapas is one of the most diverse, best preserved and largest regions of tropical forest in Mesoamerica, but its experiencing a fast land-use change process as a consequence of agrarian conflicts (Aguilar-López et al 2016, Lira-Torres et al 2012, Peterson et al 2003). The long-term conservation of V. chimalapensis and other endemic Scarabaeoidea could be threatened in future years if adequate protection practices are not implemented on Los Chimalapas forests. Acknowledgments The first author wants to thank Dr. Pedro ReyesCastillo for his advice, guidance and invaluable teachings. CONACYTMexico awarded a grant for postgraduate studies to E Ariza-Marín (no. 609153) and V Moctezuma (no. 412700). We sincerely thank the General Directorate of the Instituto de Ecología, A.C., for providing a special project to support this work (no. 20035/30916). This work was possible

with the support of Los Chimalapas residents, particularly from the communities of Benito Juárez and San Antonio. Nomenclature LSID of publication: http://zoobank.org/urn:lsid: zoobank.org:act:93152162-CA76-43E8-83F3-2E16AE1299D3 LSID of species: http://zoobank.org/urn:lsid:zoobank.org:pub: B9A19803-2ABB-4483-975B-FE4DCF619AB Funding Information The Organization for Tropical Studies (OTS) partly funded field work (Hovore-Horn Fellowship no. 3116).

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