Quedius (Distichalius) biprominulus, Cai, Yan-Peng & Zhou, Hong-Zhang, 2015

Cai, Yan-Peng & Zhou, Hong-Zhang, 2015, Three new species of Quedius elpenor group (Coleoptera: Staphylinidae: Staphylinini: Quediina) from China, Zootaxa 3947 (2), pp. 236-250 : 239-242

Quedius (Distichalius) biprominulus sp. nov.

( Figs. 2, 2-1 )

Type material. Holotype ♂, CHINA: Yunnan Province: Zhongdian County, Bitahai Nature Reserve, 3003 m, 26– 30. VII. 2000, coll. Hongzhang Zhou.

Description. Head and pronotum black; scutellum blackish brown, elytra blackish brown, with inconspicuous dark green metallic hue; abdomen dark brown, each tergite with posterior margin paler; antennae, mouth part and legs blackish brown.

BL = 10.7 mm, BW = 2.4 mm, HL/PL/EL = 1.00: 1.29: 1.64, HW/PW/EW/AW = 1.00: 1.32: 1.57: 1.41

Head ( Fig. 2 A) round, slightly wider than long, HW/HL = 1.09; eye moderately large and convex, in dorsal view tempora shorter than length of eye, gradually narrowed posteriad, HEL/HTL = 1.66; two additional setiferous punctures between anterior frontal setiferous punctures; posterior frontal setiferous puncture situated distinctly behind level of posteriomedial margin of eye, closer to posterior medial margin of eye than to nuchal constriction of head; one smaller setiferous puncture between it and temporal setiferous puncture at posterior margin of eye; temporal setiferous puncture situated about midway between posterior margin of eye and nuchal constriction, with several small setiferous punctures arranged in an oblique curve behind it; two basal setiferous punctures situated very close to nuchal constriction; head with very fine and dense microsculpture of transverse and oblique waves. Antenna somewhat robust, with segment I longer than segment II or III, segment III longer than segment II, segments IV–VII, XI longer than wide, segments VIII–X wider than long.

Pronotum ( Fig. 2 B) wider than long, PW/PL = 1.12, narrowed anteriad, posterolateral and posterior margins continuously and broadly rounded, lateral margins not explanate; three setiferous punctures in each dorsal and sublateral row, one small extra setiferous puncture between each dorsal and sublateral row, last sublateral row puncture situated behind level of large lateral setiferous puncture; surface of pronotum with microsculpture similar to that of head.

Scutellum ( Fig. 2 C) with very fine and dense microsculpture of transverse waves, impunctate.

Elytra ( Fig. 2 C) relatively long, about as wide as long, EW/EL = 1.04, ESL/EL = 0.56, slightly broadened posteriad, each elytron with surface unevenly covered with sparse coarse setiferous punctures, somewhat arranged in longitudinal rows and leaving relatively large areas of elytron impunctate, surface between punctures with microsculpture of dense microscopic punctulation. Wings fully developed.

Abdominal tergite II impunctate; setiferous punctures of other tergites much finer and denser than those of elytra, becoming sparser toward posterior margin of each tergite, and generally becoming so toward apex of abdomen; tergite VII with whitish apical seam of palisade setae.

Male first four segments of fore tarsus strongly dilated, sub-bilobed, each heavily covered with modified pale setae ventrally, segment II slightly wider than apex of tibia; sternite VII with a very inconspicuous medioapical emargination at apical margin, a very small triangular area in front of the emargination impunctate; tergite VIII with basal ridge complete, straight, without any long seta; sternite VIII ( Fig. 2-1 A) with basal ridge complete, nearly straight, with two long setae on each side, apical margin with a deep and wide medioapical emargination, a relatively large acute triangular area in front of the emargination impunctate; sternite IX ( Fig. 2-1 B) with basal portion rather wide, with one long seta on each side, apical margin rounded; tergite X ( Fig. 2-1 C) with basal side broadly and shallowly concave, apical margin widely rounded; aedeagus in lateral view ( Fig. 2-1 D) with apex of paramere not quite reaching that of median lobe, median lobe swollen at about apical 1/4 toward paramere side, with two small hook-shaped processes in characteristic shapes at apex pointing toward paramere side ( Fig. 2 E); aedeagus in parameral view ( Fig. 2-1 E) with paramere gradually narrowed in general from base to apex, but with middle third inconspicuously dilated laterally, being as wide as median lobe at widest point, apex bluntly rounded; median lobe wide at base, then evenly narrowed, and abruptly constricted into small and narrow apex ( Figs. 2 F, 2- 1G); apical portion of paramere with two long setae at apex and three subapical setae on each side, underside with 28 sensory peg setae arranged in two parallel longitudinal groups ( Figs. 2 D, 2-1F).

Female unknown.

Distribution. China (Yunnan).

Diagnosis. This new species can be distinguished from other similar species easily by elytra with dark green metallic hue in color, with sparser coarse setiferous punctures, somewhat arranged in longitudinal rows, and by the two characteristic small hook-shaped processes at apex of median lobe. However, it is also a little similar to Q. (Distichalius) phormio Smetana in male genitalia, but it can be distinguished from the latter by having more sensory peg setae on underside of paramere, arranged in two parallel longitudinal groups, median lobe abruptly constricted into small and narrow apex, with two apical processes; whereas Q. (Distichalius) phormio Smetana has fewer sensory peg setae on underside of paramere, arranged in two more laterally spread curved groups, median lobe gradually and evenly narrowed into acute apex with one hook-shaped apical process.

Etymology. The specific name is derived from Latin prefix bi - (double) and Latin adjective prominulus (projecting slightly), referring to the two characteristically shaped processes at apex of median lobe.

Figures

FIGURE 2. Quedius (Distichalius) biprominulus sp. nov.: A. head (1.0 mm); B. pronotum (1.0 mm); C. elytra (1.0 mm); D. underside of paramere (0.2 mm); E. apical portion of median lobe, lateral view (0.2 mm); F. apical portion of median lobe, parameral view (0.2 mm); G. microscopic punctulation on elytra (0.2 mm). (Scale lengths in parentheses)