Neosclerus macer, Assing, 2013

Assing, V., 2013, A revision of Neosclerus CAMERON III. Two new species from India and Laos, and additional records (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 45 (2), pp. 1549-1559 : 1552-1554

Neosclerus macer nov.sp.

( Figs 1-7 , Map 1 )

Type material: Holotype: " Laos, Phongsaly prov., 21°41'N, 102°6'E, Phongsaly env., 6.-17.v.2004, ~ 1500 m, Vít KubáĖ leg. / Holotypus Neosclerus macer sp.n. det. V. Assing 2011" ( NHMB).

Etymology: The name (Latin, adjective: skinny) refers to the slender habitus, one of the characters distinguishing this species from similar congeners.

Description: Small and slender species, 2.7 mm. Coloration: Head blackish; pronotum blackish-brown; elytra dark-brown; abdomen blackish, with the apex (segments VII-X) dark-brown. Legs and antennae yellowish.

Head moderately transverse, approximately 1.15 times as broad as long; punctation conspicuously coarse and dense, only slightly sparser in posterior portion of dorsal surface ( Fig. 1 ); interstices without microsculpture and glossy. Eyes large, but not reaching posterior margin of head; postocular portion short, but noticeable.

Pronotum approximately as long as broad and 0.85 times as wide as head; punctation as coarse and almost as dense as that of head ( Fig. 1 ); midline narrowly impunctate; interstices without microsculpture and glossy.

Elytra approximately as long as pronotum ( Fig. 1 ); punctation dense, defined, and relatively coarse, but distinctly less so than that of head and pronotum. Hind wings fully developed. Metatarsomere I longer than II, but shorter than the combined length of II and III.

Abdomen distinctly narrower than elytra; posterior margin of tergite VII with palisade fringe.

: sternite VII weakly oblong and with sparse pubescence, posterior margin with pair of small tooth-like processes ( Fig. 2 ); sternite VIII oblong, anteriorly with pair of carinae posteriorly extending into a short process with a terminal seta, posterior excision moderately deep ( Figs 3-5 ); aedeagus 0.45 mm long, ventral process subapically bent and apically acute ( Figs 6-7 ).

Comparative notes: Based on the synapomorphically derived shapes of the male sternites VII (bidentate posterior margin) and VIII (anteriorly bicarinate), as well as on the similar general morphology of the aedeagus, N. macer is undoubtedly most closely related to N. bicarinatus ASSING 2011 from Vietnam, most likely its sister species. In the key in ASSING (2011a), the new species would key out at couplet 16, together with N. glaber ASSING 2011 and N. bicarinatus . It is distinguished from both by the shape of the aedeagus, the more slender pronotum, and the distinctly coarser punctation of the elytra, from N. glaber additionally by the modifications of the male sternites VII and VIII, and from N. bicarinatus by the coarser and denser punctation of the head, the uniformly dark coloration of the elytra ( N. bicarinatus : humeral angles and posterior margin reddish), the more narrowly separated and differently shaped carinae on the male sternite VIII, as well as by the less pronounced posterior processes of the male sternite VII. For illustrations of N. glaber and N. bicarinatus see ASSING (2011a).

Distribution and bionomics: ThetypelocalityissituatedinPhongsaly province in northern Laos ( Map 1 ) at an altitude of 1500 m. The fully developed hind wings suggest that N. macer may be widespread.

Figures

Map 1: Distributions of Neosclerus macer nov.sp. (open circle) and N. barbatulus ASSING (filled and open circles) in South Asia.

Figs 1-8: Neosclerus macer nov.sp. (1-7) and N. schuelkei ASSING (8): (1) forebody; (2) male sternite VII; (3) male sternite VIII in ventral view; (4) anterior carinae of male sternite VIII in ventral view; (5) male sternite VIII in lateral view; (6, 8) aedeagus in lateral view; (7) apical portion of aedeagus in ventral view. Scale bars: 1: 0.5 mm; 2-3, 5: 0.2 mm; 4, 6-8: 0.1 mm.