Gabrius oceanicus TOTTENHAM 1956

Hromádka, L., 2011, Revision of the genus Gabrius STEPHENS 1829 from Madagascar and adjoining Islands (Coleoptera: Staphylinidae: Philonthina), Linzer biologische Beiträge 43 (2), pp. 1377-1397 : 1387

Gabrius oceanicus TOTTENHAM 1956 (Figs 32-34)

T y p e m a t e r i a l e x a m i n e d Holotype: ″ Seychelles Exp., Silhouete , 1908, // Gabrius oceanicus Tottenham TYPE [white oblong label handwritten], Percy Sladen Trust. Exped. Brit. Mus. 1926-246. // Philonthus fimbriolatus Er. , [white oblong label handwritten]″ ( BMNH).

R e d e s c r i p t i o n: Body length 5.2 mm, length of fore body (to end of elytra) 2.4 mm. Head black, pronotum reddish-brown, scutellum, elytra and abdomen brownblack, posterior margin of all tergites narrowly reddish. Maxillary and labial palpi, antennomeres 1-2 and base of antennomere 3 yellow-brown, remaining antennomeres black, mandibles brown, slightly paler distally, legs yellow-brown.

Head wider than long (ratio 18: 15) slightly narrower posteriad, posterior angles obtusely rounded, bearing several varying long bristles. Between eyes 4 punctures, distance between medial punctures 3 times as long as distance between lateral and medial puncture. Medial punctures slightly shifted anteriorly. Eyes shorter than temples (ratio 5: 7.5), posterior angles with 3 punctures arranged in oblique row. Surface lacks microsculpture.

Antennae stout and short, ar reast reach middle of pronotum when reclined, slightly widened distally. Antennomeres 1-3 and 11 longer than wide, antennomeres 4-10 slightly wider than long. Antennomere 1 twice longer than antennomere 11, as long as antennomeres 2-3 combined.

Pronotum highly convex, slightly longer than wide (ratio 18: 16.5), parallel-sided. Anterior angles obtusely rounded, bearing several short bristles, posterior angles markedly rounded. Each dorsal row with 5 approximately equidistant punctures, each sublateral row with 2 punctures, puncture 2 situated behind level of puncture 4 in dorsal row and slightly shifted to the lateral margin. Surface lacks microsculpture.

Scutellum very finely and sparsely punctate, diameter of punctures smaller than eyefacets, separated by 2 puncture diameters in transverse direction.

Elytra wider than long (ratio 24: 22), slightly widened posteriorly. Punctation coarse and sparse, diameter of punctures larger than eye-facets, separated by one or one and half puncture diameters. Surface lack microsculpture; setation greyish.

Legs. Metatibia slightly longer than metatarsus (ratio 13: 12), matatarsomere 1 as long as metatarsomere 5, almost as long as metatarsomeres 2-4 combined.

Abdomen very gradually narrowed posteriorly, punctation at base of all tergites very fine, diameter of punctures smaller than eye-facets, separated by 2 puncture diameters in transverse direction, becoming finer and sparser towards posterior margin of each tergite. Surface lacks microsculpture; setation of the same colour as that on elytra.

C o m p a r a t i v e n o t e s G. oceanicus seems to be a sister species of G. fimbriolatus , it differs in having wider head, coarser and denser punctation of elytra, coarser punctation of abdomen and by the different shape of the aedeagus.

D i s t r i b u t i o n: Seychelles ( HERMAN 2001).