Oedichirus niger, Cameron, 1914

Rougemont, Guillaume de, 2018, New oriental Oedichirus (Staphylinidae, Paederinae, Pinophilini), Linzer biologische Beiträge 50 (1), pp. 461-536 : 492-493

Oedichirus niger CAMERON (Figs 41)

Oedichirus niger CAMERON, 1914: 536.

Oedichirus niger CAMERON 1932: 30.

M a t e r i a l s t u d i e d: ♂ Holotype: [BM Holotype label] / H.L. Andrews, Nilgiri Hills [ NHML]; 1♀ syntype: [BM Paratype label] / Nilgiris / M. Cameron Bequest 1955-147 [ NHML]; 8 syntypes: Ibid, [without BM type labels, including 1♂ with an additional handwritten label " Oedichirus andrewsei Fvl."] [ NHML, one specimen in CRO].

D e s c r i p t i o n: length: 7.2 mm; length of fore-body: 3.9; length of head: 0.95; breadth of head: 1.18; length of antenna: 2; length of pronotum: 1.3; breadth of pronotum: 1.02; length of elytron: 1.3; breadth of elytra: 1.2. Head and pronotum black, elytra and abdomen piceous; palpi, antennae and legs testaceous, the apices of femora slightly and narrowly infuscate. Head and pronotum devoid of microsculpture, elytra with faint but distinct reticulate microsculpture, abdominal tergites more strongly and distinctly microsculptate, the sculpture consisting of mostly transverse micro-striae. Fore body without evident pubescence; abdomen with long pale decumbent pubescence. Habitus: Fig. 41h.

Head strongly transverse, eyes large and prominent; anterior margin of frons deeply indented; post-ocular carina and groove well marked, ending anteriad in a small angle behind posterior margin of eye; disc entirely fairly densely but irregularly punctate, leaving only the anterior margin of frons and a narrow transverse area on vertex impunctate. Pronotum strongly elongate, the sides slightly concave between anterior and posterior angles; lateral margins without evident border; puncturation of disc coarse, forming a pair of discal series of six punctures each, the surface between these slightly umbonate, with one or two punctures, and lateral series of four punctures in posterior half of pronotum, the surface of anterior 1/3 rd of disc (before discal series) with numerous punctures, and punctures along the lateral margin. Elytra elongate, humeral angles marked but narrow, the sides dilated to widest point about 2/3 rds from base, the surface of disc strongly depressed in anterior half; puncturation coarse and dense, the punctures on lateral margins of anterior ¾ asperate, forming small tubercles. Puncturation of abdominal tergites coarse and dense, disposed randomly; keels and furrows of tergites III- IV short, reduced, obsolescent on following tergites.

Male: abdominal sternite VII: Fig. 41s7, with an arcuate apical emargination, the apical angles each produced into a long stout tooth; sternite VIII with a moderately large subtriangular emargination with rounded fundus, the sculpture otherwise unmodified; aedoeagus: Fig 41arl.

O. niger is a distinctive species by virtue of the shape of its elytra (sides constricted between narrow but well marked humeral angles and their broadest point, the surface strongly depressed, concave in lateral view (notwithstanding the elongate elytra, the species probably has reduced, non-functional wings); O. niger resembles O. strictipennis nov.sp. from Thailand in its build and microsculptate abdomen, but the puncturation of the fore-body is coarser and the humeral angles are obsolescent.

Key 4.