Meligethes auropilosus, 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 : 108-109

Meligethes (s.str.) auropilosus sp. nov.

( Figs. 13–14 , 32–33 )

Diagnosis. Meligethes auropilosus sp. nov. is a member of the M. nepalensis group (as delimited by Audisio et al. 2015), where it is likely related to M. volkovichi Audisio, Sabatelli & Jelínek, 2015 and to a lesser extent to M. cinereoargenteus Audisio, Sabatelli & Jelínek, 2015 from Yunnan and Sichuan, respectively. The species of this group share uniformly blackish to dark-brown body coloration, usually with paler pronotal sides, elongate body shape (ratio LELY/WELY always markedly>1), narrow and slender metatibiae in both sexes (ratio WPTI/LPTI <0.27), combined with yellow-orange to piceous-brown legs and antennae, and peculiarly long and prostrate golden to silvery dorsal pubescence, partly obscuring dorsal surface and coloration. The new species can be easily differentiated by the peculiarly shaped male genitalia ( Figs. 13–14 ), with elongate tegmen and long and parallelsided median lobe of the aedeagus, narrowly spatulate and minutely emarginated distad (female genitalia of M. auropilosus sp. nov. and of M. cinereoargenteus are unknown; but see also Taxonomic Remarks below).

Description (male holotype). Size: Length 2.7 mm, width 1.4 mm.

Body color and pubescence: External habitus and coloration as figured ( Figs. 32–33 ); dorsal and ventral body surface uniformly blackish to dark castaneous, including pronotum; pronotal flattened lateral sides narrowly paler (nut brown) than disc; elytral lateral sides same color as disc. Antennae orange-yellowish, with darker antennal club and antennomeres preceding the club infuscate ( Fig. 33 ); legs uniformly orange-yellowish. Dorsal pubescence with peculiarly long and recumbent setae, silvery-golden and dense, partly obscuring the dorsal surface.

Dorsal habitus: body scarcely convex, elongate and oval ( Figs. 32–33 ). Ratio LPR1/LELY = 0.48; ratio WPR1/LPR1 = 1.89; ratio WPR2/LPR1 = 1.86; ratio WPR2/WPR1 = 0.98; ratio LELY/WELY = 1.02; ratio WPR1/WPRA = 1.59; ratio WPR1/WELY = 0.92; ratio WPR2/WELY = 0.91.

Anterior margin of clypeus slightly arcuately emarginate; pronotum with blunt but distinct posterior angles ( Fig. 32 ), not projecting backwards. Frons and pronotum with punctures nearly of the same size as eye facet, separated by little <1 diameter. Elytral punctures markedly finer, shallower than those on head and pronotum, smaller in size than eye facets, oval, separated by ~1 diameter, without traces of transversal strigosity. Interspaces between punctures on head and pronotum shining, only in posterior half of pronotum with faint trace of reticulation; interspaces between elytral punctures with more distinct traces of reticulation and slightly duller. Pygidium with rather dense flatly granular punctures, its apex obtusely rounded ( Fig. 33 ).

Ventral habitus ( Fig. 33 ): Prosternal process subparallel-sided, narrow, roundly pointed distad. Male metaventrite exhibiting a shallow mediolongitudinal impression, widened behind midlength, area lateral to this impression markedly convex, slightly convex, densely punctate, shining, at sides duller, without tufts of erect setae.

Appendages: antennae ( Fig. 33 ) peculiarly long and slender, exhibiting ratio ANLE/HWEA = 1.16; ratio CLLE/W10J = 1.40; ratio L03J/W03J = 2.90; ratio L03J/L02J = 1.00; ratio L03J/L04J =1.45. Protarsal plates ( Fig. 33 ) narrow, ratio WFTA/LFTA = 0.25; protibiae with minute rather sharp teeth on apical third of their outer margins ( Fig. 33 ), exhibiting a ratio LETI/WITI ≈ 3.6. Male posterior femora normally developed, when extended only moderately protruding outwards beyond the elytral sides, the ratio between the protrusion of distal apex of metafemora beyond elytral lateral edge being ca. 0.22× of the head width (HWEA) ( Fig. 33 ); meso- and metatibiae along their inner edge simple, not sinuated. Metatibiae peculiarly narrow ( Fig. 33 ), ratio WPTI/LPTI = 0.22.

Male genitalia: shape of both tegmen and aedeagus as figured ( Figs. 13–14 ), characterized by large, rather long and parallel-sided median lobe of the aedeagus, abruptly narrowed at distal fifth, with narrowly spatulate apex, ratio LEAE/WIAE = 2.40. Tegmen elongate, widest at its distal three fifths, medial distal excision moderately deep, narrowly V-shaped (ratio DTIN/LETE ≈ 0.38), its inner margins with marked projection; ratio LETE/WITE = 1.58. Main sclerites of internal sac (endophallus) rather long, rod-shaped in both dorsal and lateral view.

Female: unknown (but see Taxonomic Remarks below).

Variation: The second known specimen (paratype) resembles almost perfectly the type specimen (length 2.7 mm, width 1.4 mm) in size and body coloration.

Type material. Holotype, ♂, China: Tibet, Shigatse District, Nyalam Quxiang [ca. 28.07 ° N, 85.79 ° E], 3600 m a.s.l., 20.v.1966, Wang Shuyong lgt., 1 ♂ ( IZAS). Paratype: same data as holotype, 1 ♂ ( IZAS).

Distribution. EPA: XIZ (SHA?).

Meligethes auropilosus sp. nov. is only known with certainty from a single locality in central NW China, in middle-high altitude areas of SW Tibet; a single female from S Shaanxi could be referred to this same species or to a closely related taxon (see Taxonomic Remarks below).

Chorotype. Central-SW Chinese.

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

Habitat. Scrub, middle altitude plains, river edges; collected at ca. 3600 m a.s.l.; the single doubtful female specimen from Shaanxi (see Taxonomic Remarks below) was collected at ca. 2000 m a.s.l.

Phenology. V-VII?

DNA data. Not available.

Name derivation. Name derived from Latin aurum (= gold) and pilosus (= haired), in recognition of the main diagnostic characters of the new species, the peculiarly long and golden dorsal pubescence, partly obscuring the dark dorsal body surface.

Taxonomic remarks. Meligethes auropilosus sp. nov. is a member of a small group of related species distributed from Nepal and Bhutan westwards to SW and central China eastwards, which are easily distinguished by the different shape of male and female genitalia (see Diagnosis above). This species appears to be geographically vicariant of the more closely related M. volkovichi Audisio, Sabatelli & Jelínek, 2015 from Yunnan.

The authors recently collected and studied an additional isolated female specimen which could be this same species or more likely (considering the long distance separating the provinces of Tibet and Shaanxi), a closely related taxon: China: Shaanxi province, Taibai Mts, Mei Xian, Haopingsi Natural Protection Area, ca. 2000 m a.s.l., ca. 34.04 ° N, 107.42 ° E, 29.VII.2015, Huang, Liu & Cao lgt., 1 ♀ (NWAFU). The ovipositor of this problematic specimen is more similar in shape to that of M. nepalensis than to M. volkovichi ( Figs. 15 a-b in Audisio et al. 2015). The ovipositor of M. cinereoargenteus is unknown, but this species exhibits a larger body size, and blackish flattened pronotal sides.

Figures

FIGURES 9 – 16. Male genitalia of Meligethes spp. 9 – 10: M. aureolineatus Audisio, Sabatelli & Jelínek, 2015 (male from China, Sichuan, Jiuzhaigou Valley). 11 – 12: M. aurifer Audisio, Sabatelli & Jelínek, 2015 (male paratype from China, Shaanxi, Hua Mts). 13 – 14: M. auropilosus sp. nov. (male holotype from China, Tibet, Nyalam). 15 – 16: M. volkovichi Audisio, Sabatelli & Jelínek, 2015 (male holotype from China, Yunnan, Cang Mts). Scale bar = 0.2 mm (Figs. 9 – 16).

FIGURES 30 – 33. Habitus of Meligethes spp. (dorsal and ventral view). 30: M. aureolineatus Audisio, Sabatelli & Jelínek, 2015 (female holotype from China, Sichuan, Jiuzhaigou Valley). 31: M. aurifer Audisio, Sabatelli & Jelínek, 2015 (female paratype from China, Shaanxi, Hua Mts). 32 – 33: M. auropilosus sp. nov. (male holotype from China, Tibet, Nyalam). Scale bar = 0.6 mm (Figs. 30 – 33).