Microplinthus sherpa Meregalli, 2020

Meregalli, Massimo, 2020, Revision of the Nepalese genus Microplinthus Zherichin, 1987 (Coleoptera: Curculionidae: Molytinae), with description of 25 new species, Zootaxa 4794 (1), pp. 1-63 : 11-13

Microplinthus sherpa Meregalli n. sp.

http://zoobank.org/ urn:lsid:zoobank.org:act:3FAEAD9A-CDA0-47CF-9EE1-331C38F2BDA8

Fig. 3

Material examined: Holotype ♂: “ NEPAL Khand- / bari District // “ Bakan ” W of Ta- / shigaon [=Tashi Gaon, 27°38’N 87°12’E] 3200 m / 3.IV.1982 / A. & Z. Smetana // H. & A. Howden / Collection” ( CMNC) . Paratypes: “ NEPAL Khandbari / Distr. Forest S Man- / singma [27°30’N 87°18’E] 2200 m 12.iv. / 84 Smetana & Löbl // H. & A. Howden / Collection” 1♂ ( MER) 1♀ ( CMNC) ; “ NEPAL Khandbari / Distr. Ridge NE Mang- / maya [27°30’N 87°25’E] 2800 m 7.iv.84 / Smetana & Löbl // H. & A. Howden / Collection” 1♀ ( CMNC) .

Diagnostic description. Length 5.84 mm. Body elongate, integument matt, dark brown, distinctly reticulate. Vestiture composed of very sparse, small setae appressed to integument. Rostrum short, stout, moderately broadened apicad, dorsal margins subparallel at base and more strongly convergent apicad, in lateral view strongly curved, slightly thicker at midlength, junction with head distinctly sinuate; dorsum with dense punctures, generally merged in longitudinal impressions, delimited by narrow longitudinal lines, the median line more regularly raised from base to almost antennal insertion; apex smooth from antennal insertion. Head densely and regularly punctured. Antennal scape abruptly thickened apicad, with some slender setae directed forwards; funicle antennomeres 1 and 2 conical, at least twice as long as wide, 1 thicker than 2, 3–6 subquadrate, 7 larger, transverse; club oblong. Eye oval-oblong, with about 40 ommatidia. Pronotum 1.10x longer than wide, sides irregularly curvilinear, more strongly convergent in apical quarter; dorsum lacking a median keel, surface very irregularly sculptured, with dense punctures in part merged in short curved rows, interspaces not broader than punctures, in part raised to form obtuse humps. Elytra oblong, odd intervals with low, oblong tubercles, even intervals with irregular low humps or oblong tubercles in basal part; striae almost as wide as intervals, with poorly delimited punctures, in part not clearly differentiated. Femur slender, at midlength weakly thickened, with a small and sharp inner tooth; tibia short, with erect setae; apex curved, slightly prominent, with short oblique margin; tarsomere 3 with broad lobes, twice as wide and long as 2, outer lobe slightly smaller than inner; claws with strong inner teeth, as long as half the length of the claw. Ventrites 2–5 scarcely restricted, 1 and 2 with small deep punctures, rather evenly impressed and spaced, interspaces often broader than punctures, 3–4 short, only slightly narrower than previous ones, with a row of punctures, 5 regularly and shallowly punctured, subrectangular. Penis strongly sclerotized, sides broadened medially, less narrowed before apical lamella than the width at midlength, lateral sclerification very broad, membranous part as wide as sclerotized part; lamella very large, angularly broadened and narrowed, apex rounded; in lateral view strongly curved in median part, slightly bent horizontally at apex. Female ventrite VIII with arms curved, X-shaped with branches, joined, branches continuing curvature of arms, very long, directed downwards, plate very short, scarcely sclerotized.

Variation. The body length varies between 4.90 and 5.84 mm. The paratypes have slightly shallower sculpture, with punctures on the pronotum better differentiated and elytral humps less raised.

Differential remarks. See the description of M. newarorum for the differences from its sister species, and the descriptions of M. arunensis and M. khandbariensis for differences from those sympatric species. Microplinthus koshianus is smaller (3.9 mm), has shorter elytra and glossy integument and rostrum strongly thickened basad in lateral view.

Origin of the name. This name derives from the Sherpa people.

Distribution. Eastern Nepal. Found in the mountains to the east of the Arun valley, in Khandbari district ( Fig. 28 ).

Figures

FIGURE 3. Microplinthus sherpa, Holotype ♂, paratype ♀. Body (A, B); rostrum (F, G); antenna (C); pronotum (E); elytra (D); femur (I); foretibia and its apex (L, H); claws (O); ventrites (M); penis (J, K); female sternum VIII (N). Bar: 2 mm.

FIGURE 28. Distribution map of some species of Microplinthus. Map data: Google Earth, Maxar Technologies, used according to Google Earth Terms of Service.