Porocallus vietnamensis, Assing, 2015

Assing, Volker, 2015, A revision of Porocallus SHARP. V. The first records of the genus from Vietnam (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 47 (2), pp. 1229-1234 : 1230-1233

Porocallus vietnamensis nov.sp. ( Figs 1-7 )

T y p e m a t e r i a l: Holotype 3 [slightly teneral]: "N-Vietnam - pass 8 km NW Sa Pa , 22°21'10''N, 103°46'01''E, 2010 m, second. forest, 12.VIII.2013, V. Assing [7b+2] / Holotypus 3 Porocallus vietnamensis sp. n., det. V. Assing 2015" (cAss).

E t y m o l o g y: The specific epithet is an adjective derived from Vietnam.

D e s c r i p t i o n: Relatively large species; body length 6.8 mm; length of forebody 3.0 mm. Coloration: head blackish; pronotum and blackish brown, with the humeral angles of the elytra dark-reddish and the elytra posterior margins narrowly pale-reddish; abdomen bicoloured: segments III-V reddish with the anterior impressions of the tergites slightly darker, segments VI-VIII blackish-brown; legs yellowish-brown; antennae and maxillary palpi dark-reddish.

Head ( Fig. 1 ) 1.17 times as broad as long, broadest across eyes; punctation extremely dense and umbilicate, not confluent ( Fig. 3 ); interstices reduced to narrow ridges and with shallow microsculpture ( Fig. 3 ); surface matt. Eyes large and bulging, somewhat longer than distance from posterior margin of eye to posterior constriction in dorsal view. Antenna long and slender, 2.1 mm long; antennomeres IV-IX oblong, X approximately as long as broad, and XI slightly longer than the combined length of IX and X ( Fig. 2 ).

Pronotum ( Fig. 1 ) strongly transverse, 1.28 times as broad as long and 1.32 times as broad as head, broadest approximately in the middle; lateral margins strongly convex in dorsal view; posterior angles distinctly marked, lateral margins sinuate near posterior angles; punctation ( Fig. 4 ) similar to that of head, but somewhat confluent.

Elytra ( Fig. 1 ) 0.97 times as long as pronotum; punctation coarser than that of head and pronotum and distinctly confluent ( Fig. 5 ). Hind wings present. Metatarsomere I longer than the combined length of II-IV.

Abdomen narrower than elytra; tergites III-V with deep and coarsely punctate anterior impressions, tergites VI and VII without impressions, coarsely punctate anteriorly; remainder of tergal surfaces with rather sparse and moderately fine punctation; interstices without microsculpture and glossy; posterior margin of tergite VII with palisade fringe.

3: posterior margin of sternite VIII obtusely pointed in the middle; median lobe of aedeagus 0.95 mm long and shaped as in Figs 6-7 .

♀: unknown.

C o m p a r a t i v e n o t e s: Porocallus vietnamensis differs from its congeners by the shape of the median lobe of the aedeagus, by the coloration of the abdomen, and additionally as follows:

from the widespread P. insignis SHARP, 1888 by larger body size, the coloration of the elytra ( P. insignis : elytra usually extensively yellowish-red in the posterior two-thirds of sutural portion and with broadly yellowish-red posterior margin), the much more transverse pronotum, the less oblong antennomere X, and the confluent punctation of the pronotum and elytra;

from P. tianmuensis ( PACE, 1999) (Zhejiang) by larger body size, much longer and more slender antennae, much shorter pubescence, and the non-granulose punctation of the elytra;

from P. ligo ASSING, 2006 (Guizhou) by larger body size, the coloration of the elytra and the legs ( P. ligo : elytra dark-reddish; legs brown), less oblong antennomeres IV-X, and more acutely marked posterior angles of the pronotum;

from P. hlavaci ASSING, 2006 (Fujian) by much larger body size, the coloration of the elytra and the legs ( P. hlavaci : most of elytra dark-reddish; legs dark-brown); much longer and more slender antennae, a more transverse pronotum with more distinctly marked posterior angles, and more defined punctation of the head;

from P. wrasei ASSING, 2012 (Yunnan, Vietnam) by slightly larger body size, paler legs, and a more transverse pronotum with more convex lateral margins and with confluent punctation;

from P. sinensis PACE, 2012 (Guangxi; male unknown) by larger body size, a less transverse and differently shaped pronotum ( P. sinensis : maximal width in anterior half), the coloration of the elytra ( P. sinensis : elytra blackish), and the shorter elytra in relation to the pronotum;

from P. cicatricatus ASSING, 2015 (Yunnan) by much larger body size, much longer and more slender antennae, a matt forebody, the shape of the pronotum ( P. cicatricatus : maximal width in anterior half; lateral margin less convex; posterior angles less pronounced), denser and confluent punctation of the pronotum and elytra, and the coloration of the elytra ( P. cicatricatus : posterior angles of elytra pale-yellowish).

For illustrations of other Porocallus species see ASSING (2001, 2006, 2012, 2015a), PACE (1999, 2012), and Figs 8-9.

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: The type locality is situated at a pass to the northwest of Sa Pa, North Vietnam. The slightly teneral holotype was sifted from leaf litter and roots of herbs at the margin of a secondary deciduous forest at an altitude of 2010. The type locality is illustrated in ASSING (2015b: figure 12) and ASSING (2015c: figure 26).

Figures

Figs 1-9: Porocallus vietnamensis nov.sp. (1-7) and P. wrasei from Vietnam (8-9): forebody (1); antenna (2); median dorsal portion of head (3); median portion of pronotum (4); median portion of left elytron (5); median lobe of aedeagus in lateral and in ventral view (6-8); spermatheca (9). Scale bars: 1-2: 1.0 mm; 6-9: 0.5 mm; 3-5: 0.1 mm.