Microdolichostyrax, Gabris, Radim, Kundrata, Robin & Trnka, Filip, 2016

Gabris, Radim, Kundrata, Robin & Trnka, Filip, 2016, Review of Dolichostyrax Aurivillius (Cerambycidae, Lamiinae) in Borneo, with descriptions of three new genera and the first case of (ovo) viviparity in the long-horned beetles, ZooKeys 587, pp. 49-75 : 54-55

Taxon classification Animalia Coleoptera Cerambycidae

Genus Microdolichostyrax gen. n.

Type species.

Microdolichostyrax hefferni sp. n.

Diagnosis.

The genus Microdolichostyrax can be easily recognized by the following combination of characters: generally smaller habitus (BL 9.0-10.5), antennae 0.7 times as long as body, surface of scape slightly distorted (unique in Bornean Morimopsini ), antennomere II 0.5-0.8 times as long as antennomere III, antennomere IV longer than antennomere III, antennomere XI longer than antennomere III, antennomeres relatively short (e.g. antennomere III length/width ratio = 1.7-1.8), mandibular apex unidentate, elytra with rows of individual tubercles, and tibial spurs 2-2-2 (Figs 27-28, 34-35).

Etymology.

The name Microdolichostyrax gen. n. refers to the smaller size of the specimens belonging to the genus, and to its similarity to Dolichostyrax Aurivillius. Gender: masculine.

Description.

Female. Body elongate, BL 9.0-10.5 mm, BW 2.9-3.7 mm. Body brown; antennae, legs and palpi lighter (Figs 27, 34). Body densely clothed with very short yellowish or chestnut brown pubescence, incorporating fine detritus particles.

Head slightly wider than anterior pronotal margin; genae convex at frontal view; frontoclypeus with midline running from interantennal groove to labrum, sparsely punctured; antennal tubercles prominent with deep depression in between; anterior margin of anteclypeus shallowly emarginate, with sparse long yellowish semi-erected setae. Labrum free, transverse, glabrous, with sparse long semi-erect setae (Figs 30, 36). Eyes rather small, reniform, vertically elongate, slightly emarginate at antennal articulations, lower lobes narrower than genae. Antennae 11-segmented, 0.7 times as long as body; scape enlarged, slightly curved, longest, reaching about half of pronotum, gradually widened towards apex, thickest at apical part, surface slightly distorted, not smooth, covered with very short dense pubescence; the rest of antennomeres with sparser pubescence, pedicel very small, shortest, the relative ratio of antennomere lengths: I–IV 3.2-3.9: 0.5-0.8: 1.0: 1.1-1.3; antennomere III relatively wide (length/width ratio = 1.7-1.8), antennomere V slightly shorter than IV, antennomeres VI–X subequal in length, apical antennomere simple, 1.4-1.5 times as long as antennomere III (Figs 31, 37). Mandibles short and broad; apex unidentate (Fig. 6). Maxillary palpi 4-segmented, apical palpomere fusiform (Fig. 7). Labial palpi 3-segmented, apical palopmere fusiform.

Prothorax sub-cylindrical, 0.9-1.0 times as long as wide, widest at middle, gradually narrowed towards posterior margin, laterally with one small obtuse tubercle; pronotal disc weakly convex, sparsely covered with deep puncturation, with a pair of tubercles near middle and one median at second half; anterior and posterior angles obtuse; pronotal tubercles punctured (Figs 27, 34). Prosternum in front of coxae 0.8-0.9 times shorter than diameter of coxal cavity, procoxal cavities circular, narrowly separated (Fig. 29). Scutellum transverse, more than three times as wide as long. Elytra elongate, 1.6-1.8 times as long as wide at widest part, 2.1-2.3 times as long as pronotum, basally slightly wider than posterior pronotal margin, widest near middle, from middle gradually tapered towards apex; each elytron with three rows of irregular, slightly elevated tubercles (Figs 27, 34), sparsely covered by large deep punctures irregularly in rows, surface not wrinkled; outer elytral margin curved at lateral view (Figs 28, 35). Mesoventrite with anterior edge on different plane than metaventrite. Mesocoxal cavities circular, separated slightly wider than in procoxal cavities. Metaventrite transverse, more than two times wide as long, posterior margin emarginated, with wide, moderately deep median emargination. Metacoxal cavities separated as widely as mesocoxal ones, extending laterally to meet elytra (Fig. 29). Hind wing absent. Legs long, slender; femora weakly swollen distally, tibial spurs 2-2-2, protibiae with pubescent groove (antennal cleaner) on inner face, mesotibiae with pubescent groove on outer face, metatibiae without groove; tarsal formula 4-4-4; relative lengths of metatarsomeres 1.0: 0.6: 1:0: 1.6-1.7; last tarsomere with four long erected setae at ventral face, claws simple, empodium absent.

Abdomen with five ventrites (Fig. 29), first ventrite (excluding intercoxal process) almost two times longer than second; intercoxal process short, broadly rounded. Fifth ventrite with apex truncate, margin with sparse semi-erect pubescence. Female genitalia with ovipositor elongate, narrow, apically with short styli (Figs 32, 38). Vagina narrow, with pair of vaginal plates. Bursa copulatrix small. Spermatheca present, well-sclerotized, elongate, more or less curved, apex rounded or tapered; sclerotized part of spermathecal duct short or very long, strongly coiled (Figs 33, 39).

Male unknown.

Distribution.

Malaysia: Borneo (Sabah).