Meligethes (Odontogethes) aurorugosus, Liu, Meike, Yang, Xingke, Huang, Min, Jelínek, Josef & Audisio, Paolo, 2016

Liu, Meike, Yang, Xingke, Huang, Min, Jelínek, Josef & Audisio, Paolo, 2016, Four new species of Meligethes Stephens from China and additional data on other species of the genus (Coleoptera: Nitidulidae: Meligethinae), Zootaxa 4121 (2), pp. 101-116 : 109-115

Meligeth es (Odontogethes) aurorugosus sp. nov.

( Figs. 17–18 , 36–37 )

Diagnosis. Meligethes aurorugosus sp. nov. is a member of the subgenus Odontogethes (see Audisio et al. 2015), where it appears to be related only to a single species recently described from W Nepal, M. (Odontogethes) aurantirugosus Audisio, Sabatelli & Jelínek, 2015 . Both species share in fact, among other Odontogethes, the same rather uniformly yellowish to rusty-orange body dorsal coloration, combined with fine but strong and almost complete transverse elytral strigosity. The new species can be otherwise easily differentiated by the much longer and uniformly distributed golden dorsal pubescence, the paler (yellowish-orange) dorsal coloration, and the similarly shaped but more slender male genitalia, with V-shaped and much less deep distal excision of the tegmen ( Figs. 17, 19 ). Female genitalia of both species are unknown.

Description (male holotype). Size: Length 2.8 mm, width 1.7 mm.

Body color and pubescence: External habitus and coloration as figured ( Figs. 36–37 ); dorsal body surface uniformly yellowish-orange on elytra, while being slightly darker (pale brown-castaneous) on head and discal portion of pronotum; ventral surface mostly brownish-castaneous, with paler (yellowish-orange) prosternum and last four visible abdominal ventrites. Antennae yellowish, with slightly darker (pale brown) antennal club; legs entirely yellowish. Pubescence on head, pronotum and elytra with peculiarly long, dense and recumbent golden setae (this character state is markedly atypical among members of the subgenus Odontogethes), uniformly distributed, partly obscuring the dorsal surface.

Dorsal habitus: body moderately convex, relatively wide and short ( Fig. 36 ). Ratio LPR1/LELY = 0.53; ratio WPR1/LPR1 = 1.90; ratio WPR2/LPR1 = 1.88; ratio WPR2/WPR1 = 0.99; ratio LELY/WELY = 0.90; ratio WPR1/WPRA = 1.52; ratio WPR1/WELY = 0.91; ratio WPR2/WELY = 0.90.

Anterior margin of clypeus slightly and widely arcuately emarginated; pronotum with blunt but distinct posterior angles ( Fig. 36 ), not projecting backwards. Frons and pronotum with punctures nearly of the same size as eye facet, separated by <1 diameter. Elytral punctures slightly finer, shallower and more dense than those of pronotum, slightly smaller in size than eye facet, oval, separated by <1 diameter, with fine, marked and almost complete transversal strigosity. Interspaces between punctures on head, pronotum and elytra shining. Pygidium with obtusely rounded apex ( Figs. 36–37 ).

Ventral habitus: Prosternal process subparallel-sided, narrow, roundly pointed distad. Male metaventrite exhibiting a barely distinct longitudinal impression, widened and slightly deeper behind its midlength, area lateral to this impression markedly convex, moderately convex, densely punctate, shining, without tufts of erect hairs.

Appendages: antennae ( Fig. 37 ) rather short, exhibiting ratio ANLE/HWEA = 0.84; ratio CLLE/W10J = 1.20; ratio L03J/W03J ≈ 2.60; ratio L03J/L02J = 0.90; ratio L03J/L04J = 1.20. Protarsal plates ( Fig. 37 ) moderately wide, ratio WFTA/LFTA ≈ 0.30; protibiae with minute rather sharp teeth on apical third of their outer margins ( Fig. 37 ), exhibiting a ratio LETI/WITI ≈ 3.3. Male metafemora normally developed, when extended protruding outwards beyond the elytral sides as in most other known species of the genus, the ratio between the protrusion of distal apex of male metafemora beyond elytral lateral edge being less than 0.22× of the head width (HWEA) ( Fig. 37 ); this character state is combined with not sinuate, simply arcuated male meso- and metatibiae along their inner edge ( Fig. 37 ). Posterior tibiae only moderately elongated, ratio WPTI/LPTI = 0.32.

Male genitalia: shape of both tegmen and median lobe of aedeagus as figured ( Figs. 17–18 ), characterized by moderately developed median lobe of aedeagus, abruptly narrowed distad, widest at its distal two thirds, with minutely and rather obtusely pointed apex, ratio LEAE/WIAE = 1.81. Tegmen wide, rather short and parallelsided, medial distal excision moderately deep and widely V-shaped (ratio DTIN/LETE ≈ 0.30), inner margin without any projection, paramera obtusely and widely rounded distad; ratio LETE/WITE = 1.45. Main sclerites of internal sac (endophallus) small and rod-shaped.

Female: unknown.

Type material. Male holotype: China: Tibet, Nyingchi [= Linzhi; ca. 29.39 ° N, 94.22 ° E], 3050 m a.s.l., 07.viii.1983, Han Yinheng lgt., 1 ♂ ( IZAS).

Distribution. EPA: XIZ.

Meligethes aurorugosus sp. nov. is only known from a single locality in SW China (high altitude areas of the SE Tibet) along the high Valley of the Brahmaputra River.

Chorotype. Tibetan.

Host-plants. Unknown. Probably associated with mountain Rosaceae , perhaps Rubus spp. or allied genera.

Habitat. Scrub in high altitude plains; collected at more than 3000 m.

Phenology. VIII.

DNA data. Not available.

Name derivation. Named from Latin aurum (= gold) and rugosus (= strigose), to recall the main diagnostic characters of the new species, the unusually (in Odontogethes) long and golden dorsal pubescence, the orangegolden dorsal coloration, and the markedly transversely strigose elytra.

Taxonomic remarks. Meligethes aurorugosus sp. nov. among other members of the subgenus Odontogethes is probably more closely related to M. (Odontogethes) aurantirugosus Audisio, Sabatelli & Jelínek, 2015 from W Nepal, from which is easily distinguishable by the much longer and golden dorsal pubescence, and the different shape of male genitalia, chiefly the tegmen (see Diagnosis above).

A single male specimen of a closely related but probably distinct species has been studied by the authors from a lower altitude area in the same Nyingchi district, again along the Valley of the Brahmaputra River (Motuo, Bangxinxiang, 1300 m a.s.l.). This isolated specimen, with damaged male genitalia (IZAS), does not presently allow the possible description of a new species, which we prefer to postpone until the collecting of additional material from the same Chinese middle-altitude mountain areas or from neighboring NE Indian Arunachal Pradesh.

Figures

FIGURES 17 – 25. Male genitalia of Meligethes spp. 17 – 18: M. aurorugosus sp. nov. (male holotype from China, Tibet, Nyingchi). 19 – 20: M. aurantirugosus Audisio, Sabatelli & Jelínek, 2015 (male holotype from Nepal, W of Chainpur). Distal portion of the ovipositor of Meligethes spp. 21: M. macrofemoratus sp. nov. (female paratype from China, Ningxia Hui Autonomous Region, Xixia Valley). 22: M. scrobescens Chen, Lin, Huang & Yang, 2015 (female from China, Sichuan, Jiuzhaigou Valley). Outline of metatibiae of M. macrofemoratus sp. nov. (male and female paratypes from China, Ningxia Hui Autonomous Region, Xixia Valley). 23: male. 24: female. 25: Prosternal process of M. macrofemoratus sp. nov. (male paratype from China, Ningxia Hui Autonomous Region, Xixia Valley). Scale bar = 0.2 mm (Figs. 17 – 22); = 0.4 mm (Figs. 23 – 25).

FIGURES 34 – 37. Habitus of Meligethes spp. (dorsal and ventral view). 34 – 35: M. scrobescens Chen, Lin, Huang & Yang, 2015 (male from China, Sichuan, Jiuzhaigou Valley). 36 – 37: M. aurorugosus sp. nov. (male holotype from China, Tibet, Nyingchi). Scale bar = 0.6 mm (Figs. 34 – 37).