Geotragus declivis, Ren, Li, Alonso-Zarazaga, Miguel A. & Zhang, Runzhi, 2013

Ren, Li, Alonso-Zarazaga, Miguel A. & Zhang, Runzhi, 2013, Revision of the Chinese Geotragus Schoenherr with description of three new species (Coleoptera: Curculionidae: Entiminae), Zootaxa 3619 (2), pp. 161-182 : 170-172

Geotragus declivis sp. nov.

( Fig. 5 )

Diagnosis. This new species is allied to Geotragus tuberculatus Chen , but it can be distinguished from the latter by the following characters: surface of elytra only raised and expanded along basal 1/3, forming longtitudinal crests, and slightly raised just before declivity, forming short tubercles (instead of forming three consecutive tubercules as in G. tuberculatus ). It is also close to G. brevidens but differs from it in its flat frons and convex eyes (as opposed to moderately flat in G. brevidens ) and elytral interstria 5 not distinctly raised along base, with tubercle only distinct at declivity.

Description. Holotype-male. Measurements (in mm): Standard length: 6.40; pronotal length: 1.78; pronotal width: 1.98; elytral length: 4.40; elytral width: 2.81; rostral length: 1.00; rostral width: 0.88.

Habitus and color ( Fig. 5 A, 5B): Integument reddish brown to dark brown, antennae and legs reddish brown; with coppery metallic white to yellowish brown scales, scales large, imbricate; scales on dorsal surface of rostrum sparse, round to oval, on lateral surfaces of rostrum oval; posterior half of antennal scrobes glabrous; pronotum with round scales, imbricate; scales on elytra round, dense, imbricate; scales on ventrites moderately dense, round to oval, gradually narrowing from ventrite 1, so ventrite 5 with oval scales; body with recumbent to subrecumbent sparse setae; rostrum covered with subrecumbent fine setae; setae of antennal scape and desmomeres 1–7 moderately long, fine and sparse; setae of interstriae fine, sparse; setae on ventral surface fine and dense, subrecumbent.

Head ( Fig. 5 C): Moderately flat, dorsal surface wrinkled, punctures small and dense; eyes quite convex, with a moderately deep circumocular sulcus; frons flat, on the same plane with rostrum in lateral view.

Rostrum ( Fig. 5 C): In dorsal view, 1.14× length of wide; greatest width at base, base of rostrum as wide as frons; dorsal surface slightly depressed in median area of rostrum, with a wide, median and moderately deep sulcus, extending from antennal insertion to vertex, with a longitudinal short keel on each side of median sulcus, gradually approaching to median sulcus and extending from antennal insertion to base of rostrum; dorsal surface corrugated, densely punctured; epistome broad, posterior angle of epistome 100°, not forming a distinct carina; mandible scars oblong; both margins of scrobes carinated, in dorsal view ventral margin bisinuate, visible from apex to middle of rostrum; in lateral view, lateral surface flat between eyes and antennal scrobes, with a deep sulcus near ventral margin of rostrum.

Antennae: Scape short, stout, reaching but not surpassing middle of eyes, 0.83× length of funicle; desmomere 1 elongate clavate, gradually widened towards apex, apex stout, 1.30× length of desmomere 2, slightly shorter than 2 and 3 combined; desmomere 2 elongate clavate; desmomeres 3 and 4 equal in length, slightly elongate moniliform, combined 0.96× length of desmomere 2; desmomere 5 0.91× length of 4, moniliform; desmomere 6 1.20× length of and slightly wider than 5, elongate moniliform; desmomere 7 1.25× length of and much wider than 6, rounded; pubescence of funicle similar throughout; club segment 1 0.85× length of 2, segment 2 0.95× length of 3; segment 3 with a marked annulus at middle.

Pronotum: 0.90× as long as wide, slightly transverse; anterior and posterior margin slightly curved; disc with a discontinuous longitudinal fine furrow; posterior margin distinct carinate, moderately thick; dorsal surface of pronotum with large and round granules, granules slightly flat at top, close to each other, some granules joined together forming wide wrinkles, each granule with one recumbent fine seta on top; postocular vibrissae long.

Scutellum: Small , indistinct.

Elytra: Base not truncate; in lateral view moderately convex; in lateral view, lateral margins clearly diverging from base to basal 1/4, then subparallel, reaching its greatest width nearly at mid length, thence clearly converging towards the apex, apex W-shaped; all interstriae similarly raised; interstria 1 strongly raised at declivity, forming prominent longitudinal crest, top of crest sub-rectangular in lateral view; interstria 3 much wider than remaining interstriae, distinctly raised and expanded along basal 1/3 forming a longitudinal crest, slightly raised just before declivity forming short tubercles; interstria 5 irregularly raised from basal 1/4 towards declivity, more strongly so at declivity, forming two elongate-oval tubercles before declivity and one cone-like tubercle at declivity; interstriae 3 and 9 coalescing, slightly raised at declivity but not forming tubercles.

Abdomen ( Fig. 5 D): Surface of ventrite 1 deeply depressed at middle and convex on lateral areas; suture I strongly bisinuate; ventrite 2 moderately flat medially, without apical transverse impression; mesal length of ventrites 1 1.12× length of 2, ventrite 2 1.34× length of 3 and 4 combined; ventrite 5 moderately convex, widely parabolic.

Legs: Short; protibiae bent inwards at apical 1/5, inner margin moderately bisinuate, outer margin almost straight except apical 1/5; inner margin of protibiae with 11 moderately large, blunt teeth, each tooth with a spiniform seta just behind it, length of the longest denticle subequal to 1/5 width of tibia at the same point; teeth of meso- and metatibiae fewer and smaller than protibiae; protibial mucro small, distinct, not covered by setae; tarsi slender; tarsomere 1 2.0× length of 2.

Male genitalia and terminalia: Penis ( Fig. 5 E, 5F) in dorsal view with tube 2.81 mm in length, ca. 6.6× length of wide, temones 1.17 mm long; lateral margins subparallel at middle, slightly expanded at ostium level, thereafter converging straight, apex truncate; in lateral view strongly curved near base; greatest width near base; tegmen much shorter than penis, with ring narrow.

Female. Unknown.

Material Examined. Holotype: 3: (white): [Yúnnán, printed], [Yúnlóng Zhìbēnshān, handwritten] / 2430m [handwritten] / [ Zhōngguó Kēxuéyuàn, printed]; (white): 1981. VI.24. [handwritten] / [Cǎijízhĕ, Wáng Shūyǒng, printed]; (red, printed): HOLOTYPE; (white, printed): IOZ(E) 905055.

Holotype is to be conserved in IZCAS.

Distribution. China: Yunnan (Yunlong).

Etymology. The specific epithet is given in reference to the distinct sub-rectangular declivity of the species in lateral view.

Remarks. The holotype had been previously dissected. Only the penis and tegmen were preserved and attached to a paper card; sternite VIII was missing.

Figures

FIGURE 5. Geotragus declivis sp. nov., male, holotype: A habitus, dorsal view B habitus, lateral view C head, dorsal view D ventrites, ventral view E penis, dorsal view F penis, lateral view. Scales: A – C: 1 mm; D – F: 0.5 mm.