Pseudolathra sepikensis ( LAST , 1984) Assing, 2014

Assing, V., 2014, A revision of Palaearctic and Oriental Pseudolathra. IV. New species, new combinations and additional records (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 46 (2), pp. 1151-1166 : 1154-1156

Pseudolathra sepikensis ( LAST, 1984) , nov.comb.

( Figs 1-5 , Map 2 )

Lathrobium sepikense LAST, 1984: 120 .

Type material examined: Paratypes: 1: "S 266, Blackwater River , N.G. 6.74. / Manchester Museum, Paratype / Paratype / F3008.5149 / Lathrobium sepikensis [sic] sp.n., H.R. Last. det., Paratype / Pseudolathra sepikensis (Last) , det. V. Assing 2014" ( MMUM); 1: "S 266, Sepik, NG. 6.74 / Manchester Museum , Paratype / Paratype / F3008.5150 / Lathrobium sepikensis [sic] sp.n., H.R. Last. det, Paratype" ( MMUM) .

Comment: The original description is based on a male holotype and a female paratype from "Yentchan, main River, Sepik " and three paratypes from "Blackwater River, Sepik " ( LAST 1984). An examination of the above two paratypes revealed that this species belongs to Pseudolathra .

Redescription: Small species; body length 4.4-4.8 mm; length of forebody 2.7 mm. Coloration: body blackish-brown to blackish, with the posterior margins of the abdominal segments VII and VIII broadly reddish-yellow, distinctly contrasting with the remainder of the body; legs yellowish; antennae brown, with the apical 2-4 antennomeres, antennomere I, and the bases of the remaining antennomeres pale-reddish.

Head ( Fig. 1 ) approximately 1.1 times as broad as long, subparallel behind eyes; punctation coarse and sparse on dorsal surface, median dorsal portion more or less extensively impunctate; microsculpture absent. Eyes large, distinctly longer than postocular region in dorsal view. Antenna slender, 1.7-1.8 mm long; all antennomeres oblong.

Pronotum ( Fig. 1 ) short, 1.06-1.09 times as long as broad and 1.00-1.02 times as broad as head; lateral margins nearly straight in anterior two-thirds in dorsal view; dorsal series composed of approximately 11-14 macropunctures; midline broadly impunctate; laterad of dorsal series with rather sparse and coarse punctation; microsculpture absent.

Elytra (Fig. 1) 1.04-1.06 times as long as pronotum; epipleural line absent (lateral view); punctation rather fine, arranged in series. Hind wings fully developed. Metatarsomere I slightly longer than II. Protarsomeres I-IV strongly dilated in both sexes.

Abdomen as broad as, or narrower than elytra; punctation very dense and very fine, somewhat sparser on tergite VII than on tergites III-VI, sparse on tergite VIII; interstices with microreticulation, matt; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII strongly convex.

: sternite VII ( Fig. 2 ) moderately transverse and with weakly modified pubescence, posterior margin weakly concave; sternite VIII ( Fig. 3 ) weakly transverse, posterior excision U-shaped; aedeagus ( Figs 4-5 ) 0.85 mm long; ventral process subapically with pronounced tooth; dorsal plate long, thin, and lamellate.

Comparative notes: Characters suggesting a closer relationship to any of the species known from the Oriental and Palaearctic regions were not found. Pseudolathra sepikense is characterized by numerous characters, particularly its small body size, the absence of an epipleural line, the shape of the male sternite VIII, and the morphology of the aedeagus. The absence of an epipleural line is remarkable, since the presence of such a line was previously considered one of the main characters distinguishing Pseudolathra from Lathrobium GRAVENHORST, 1802 and some other lathrobiine genera. Interestingly, an analogous reduction of the epipleural line was observed also in one species group of Lobrathium MULSANT & REY, 1878 from Taiwan ( ASSING 2010).

Distribution and natural history: The type locality is a river basin in the north of Papua New Guinea ( Map 2 ). According to LAST (1984), two of the type specimens were collected in "aquatic vegetation by a swampy creek".

Figures

Map 2: Distributions of Pseudolathra armata (black triangles), P. bisinuata (star), P. sepikensis (white circle), P. naviculum (black circle), P. puncta (white triangle), and P. cyanea (diamond).

Figs 1-5: Pseudolathra sepikensis (LAST), paratype: (1) forebody; (2) male sternite VII; (3) male sternite VIII; (4-5) aedeagus in lateral and in ventral view. Scale bars: 1: 1.0 mm; 2-5: 0.5 mm.