Microplinthus messneri 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 : 13

Microplinthus messneri Meregalli n. sp.

http://zoobank.org/ urn:lsid:zoobank.org:act:2EAFC4C3-A900-4201-A65A-AF458BAF28B9

Fig. 4

Material examined: Holotype ♂: “ NEPAL: 324 Panchthar / Distr., Dhorpar Kharka [approximately 27°05’N 87°55’E] / 13–16.IV.1988 2700 m / leg. W. Schawaller ” ( SMNS) . Paratypes: same data as the holotype, 1 ♂ ( MER) 1 ♀ ( SMNS) .

Diagnostic description. Length 3.52 mm. Body oval, slightly glossy, scarcely reticulate. Vestiture composed of sparse setae, relatively thick, on elytra slightly spatulate, obliquely inserted and slightly recumbent, thickened on tubercles. Rostrum relatively slender, weakly broadened apicad, dorsal sides subparallel from base to midlength, then weakly convergent apicad, in lateral view scarcely curved, dorsum in profile almost rectilinear, sculpture composed of deeply impressed punctures, reciprocally isolate, separated by transverse-oblique interspaces, dorso-lateral longitudinal lines irregularly developed, obtuse, median line not clearly differentiated. Head with large deep punctures. Antennal scape short, strongly thickened apicad, with a few narrow setae; funicle antennomere 1 short, subglobose, as long as wide, 2 conical, longer than wide, 3–6 globose, 7 slightly transverse; club oval. Eye with about 30 ommatidia. Pronotum as long as wide, sides regularly curvilinear, maximum width at midlength, median line sharply raised, almost continuous on the entire length; dorsum densely sculptured, punctures reciprocally isolate, interspaces very narrow, raised, often slightly higher on external part. Elytra convex, oblong, intervals with oblong moderately raised tubercles and umbilicate broad granules bearing a seta; striae scarcely deepened, irregular, with spaced round punctures shallowly impressed, interspaces often as long as the punctures. Femur scarcely thickened medially, with a low obtuse median relief, not sharply tooth-like. Tibia short, slender, moderately sinuate internally, apex narrowed, obliquely extended along lateral part of tibia. Tarsomere 3 scarcely widened, claws with strong inner teeth. Ventrites regularly narrowed from 2 to 5, 1 and 2 deeply punctured, 5 short. Penis strongly curved downwards, apex sharply acute. Female sternum VIII lacking an apodeme, arms shortly narrowed, branches slender, elongate, feebly curved upwards, lamina subquadrate, sclerotization broad.

Variation. Body length in the three specimens varies between 3.56 and 3.68 mm. The morphologic characters are quite uniform among them.

Differential remarks. The species that live in close proximity are M. maior , M. minor and M. ausobskyi . Microplinthus messneri differs from the first two species by the short, oval, convex elytra (elongate in M. minor and M. maior ), the penis strongly curved and acutely pointed (scarcely curved and rounded at apex in M. minor ) and the female sternum VIII lacking an apodeme, with arms not joined (arms joined and apodeme present in M. maior ). Microplinthus ausobskyi has the rostrum in lateral view very thick and strongly curved (see figures in Meregalli 2003, 2004).

Origin of the name. This species is named after the famous Italian mountaineer and explorer Reinhold Messner who was the first climber to ascend all fourteen peaks over 8000 meters high, among which is Kangchenjunga, 8586 m, the nearest high mountain to the habitat of this species.

Distribution. Eastern Nepal, near the border with Darjeeling ( Fig. 28 ).

Figures

FIGURE 4. Microplinthus messneri, Holotype ♂, paratype ♀. Body (A, B); rostrum (F, G); antenna (C); pronotum (E); elytra (D); femur (N); foretibia (H); tarsus (O); claws (P); ventrites (I); penis (K, L, M); female sternum VIII (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.