Dolichostyrax Aurivillius, 1911

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 : 50-51

Taxon classification Animalia Coleoptera Cerambycidae

Genus Dolichostyrax Aurivillius, 1911

Dolichostyrax Aurivillius, 1911: 194.

Dolychostyrax Breuning, 1950: 162 (incorrect subsequent spelling).

Type species.

Dolichostyrax moultoni Aurivillius, 1911.

Diagnosis.

Dolichostyrax differs from Microdolichostyrax gen. n. and Eurystyrax gen. n. by longer antennae (0.9-1.3 times as long as BL vs. 0.6-0.7, respectively), antennomere XI shorter than III (Figs 5, 16, 24, 31, 37, 44), relatively thinner antennomeres (antennomere III length/width ratio = 3.2-4.1 vs. 1.7-2.4, respectively), and metatarsomere III longer than metatarsomere I. Borneostyrax gen. n. differs from Dolichostyrax by bidentate mandibular apex (vs. unidentate; Figs 6, 52), elytra with tubercles forming distinct ridges (vs. rows of individual tubercles; Figs 2, 48, 60), distinct protrusions on apices of protibiae and mesotibiae along with tibial spurs 0-0-2 in males (vs. no protrusions and tibial spurs 2-2-2; Figs 8, 54), and terminal maxillary and labial palpomeres widened, flattened and truncate in males (vs. fusiform; Figs 7, 53).

Redescription.

Body elongate to broadly oval, 9.4-11.8 mm long and 3.5-4.3 mm wide in males, and 11.1-12.5 mm long and 4.3-4.9 mm wide in females. Body coloration brown to black; antennae, palpi and legs (or only appendage joints) lighter (Figs 1-2, 13-14, 21-22). Body densely clothed with very short yellowish to light brown pubescence, incorporating fine detritus particles.

Prothorax sub-cylindrical, 0.9-1.1 times as long as wide, widest slightly before middle, then gradually narrowed towards posterior margin, laterally with one small more or less distinct tubercle; pronotal disc weakly convex, sparsely covered with deep puncturation, with more or less distinct, smooth or punctured tubercles (Figs 1, 13, 21), anterior and posterior angles obtuse. Prosternum in front of coxae 0.6-0.7 times shorter than diameter of coxal cavity, procoxal cavities circular, with lateral extension, narrowly separated. Scutellum transverse, widely rounded apically, about 3-4 times as wide as long. Elytra elongate, 1.4-1.6 times as long as wide at widest part, 1.6-1.9 times as long as pronotum in males and 1.8-2.3 times in females, basally slightly wider than posterior pronotal margin, widest near middle, from middle gradually tapered towards apex, fused along the elytral suture; each elytron with three rows of tubercles irregular in shape and size (Figs 1, 13, 21), sparsely covered by large deep punctures arranged irregularly in rows; outer elytral margin curved at lateral view (Figs 2, 14, 22). 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 as wide as long, posterior margin emarginated, with short narrow median groove. Metacoxal cavities separated as widely as mesocoxal ones, extending laterally to meet elytra. Hind wings 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: 0.7-1.0: 1.2-1.5: 1.8-2.4; last tarsomere with four long erected setae at ventral face, claws simple, empodium absent.

Abdomen with five ventrites (Fig. 3), 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. Male genitalia with tegmen elongate, widest before middle, basally with or without strut; parameres elongate, less than half of phallobase length, setose apically (Figs 11-12, 19-20). Penis weakly curved at lateral view, apically truncate; dorsal struts diverged from about 1/2 of penis length. Internal sac long, with paired small medial sclerites and distinct flagellar sclerites (Figs 9-10, 17-18). Female genitalia with ovipositor elongate, narrow, apically with short styli (Fig. 25). Vagina narrow, with pair of vaginal plates. Bursa copulatrix small. Spermatheca present, well-sclerotized, simple, slender, elongate, curved; sclerotized part of spermathecal duct simply coiled, distinctly shorter than spermatheca itself (Fig. 26).

Distribution.

Malaysia: Borneo (Sarawak: Dolichostyrax moultoni Aurivillius, 1911; Sabah: Dolichostyrax longipes Aurivillius, 1913), Indonesia (Sumatra: Dolichostyrax basispinosus Breuning & de Jong, 1941; Java: Dolichostyrax tuberculatus Fisher, 1936; Dolichostyrax cylindricus Breuning, 1939).