Microplinthus newarorum 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 : 9-11

Microplinthus newarorum Meregalli , n. sp.

http://zoobank.org/ urn:lsid:zoobank.org:act:8D6BAC11-B4B2-47AE-A60F-9E5B8944D9D7

Fig. 2

Material examined: Holotype ♂: “ NEPAL Lalitpur / Distr. Phulcoki [= Phulchowki, 27°34’N 85°24’E] / 2600 m 14.X.83 Smetana & Löbl // H. & A. Howden / Collection” ( CMNC).

Diagnostic description. Length 4.26 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 irregular narrow longitudinal rows of deep irregular subquadrate punctures, separated by narrow transverse interspaces, delimited by very irregular narrow longitudinal lines; apex smooth from antennal insertion. 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 shortly oval. Eye oval-oblong, with about 40 ommatidia. Pronotum slightly longer than wide, sides irregularly curvilinear, more strongly convergent in apical quarter; dorsum lacking a median keel, all surface irregularly sculptured, punctures very small, bearing a short yellowish seta inserted at lateral or inferior margin, interspaces among punctures broader than punctures, irregularly raised. Elytra oblong, odd intervals with low elongated tubercles, almost contiguous on base of interval 3, even intervals almost flat, with irregular low humps; striae almost as wide as intervals, with round or elongated, well delimited punctures, interspaces between two punctures shorter than punctures. 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 small sharp inner teeth. 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 punctured, subrectangular. Penis strongly sclerotized, sides broadened medially, narrowed before apical lamella, this very large, broadened and narrowed, so sides of penis in its entirety bisinuate, apex rounded; in lateral view strongly curved in basal part, slightly bent horizontally at apex.

Differential remarks. Three species were found on Phulchowki mountain, this one, M. phulchowkianus and M. godawaricus . The two latter species have simple claws, M. phulchowkianus has the penis completely different, wherae M. godawaricus , only known from a female specimen, has very slender elytra and a pronotum with dense punctures, almost glossy integument and an irregular glossy median line. Microplinthus newarorum is the sister species of M. sherpa , a species that lives much further east and differs in its larger size (4.9–5.8 mm), oblong antennal club (oval in M. newarorum ), pronotum with dense and deep sculpture, punctures often barely delimited, with narrow and convex interspaces, elytra broader, ratio length /width 1.5 (elytra slenderer, ratio l/w 1.7 in M. newarorum ), basal part of even elytral intervals with a larger number of humps and tubercles, and striae with punctures merged in rows. The penis of the two species is very similar, although in M. sherpa it has a slightly angularly broadened lamella and a slightly shorter apex.

Origin of the name. The name derives from the Newar people, who were the first settlers, about one thousand years ago, in the region where the species was found.

Distribution. Central Nepal. Phulchowki mountain is 2750 m in elevation, approximately 20 km SE of Kathmandu ( Fig. 28 ).

Figures

FIGURE 2. Microplinthus newarorum, Holotype ♂. Body (A, B); rostrum (G, H); antenna (D); pronotum (F); elytra (E); femur (M); foretibia and its apex (K, N); tarsus (C); claws (L); ventrites (O); penis (I, J). 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.