Australocyon keralensis ( Hebauer, 2002 ) Hebauer, 2002

Fikáček, Martin, Jia, Fenglong & Prokin, Alexander, 2012, A review of the Asian species of the genus Pachysternum (Coleoptera: Hydrophilidae: Sphaeridiinae), Zootaxa 3219, pp. 1-53 : 48

Australocyon keralensis ( Hebauer, 2002) , comb. nov.

Pachysternum keralense Hebauer, 2002a: 16 .

Pachysternum keralense: Short & Hebauer (2006: 349, catalogue) .

Type material examined. Paratype: 1 spec. ( NMPC): “ INDIEN: Kerala / Thekkady, Peryar W. L. S. / 2. 9. 1989 / leg. A. Riedel ”

Taxonomic note. The species bears all diagnostic characters of the Australocyon pilocnemoides species group mentioned by Hansen (2003), and moreover differs from Pachysternum species by the antennal grooves not reaching the lateral margin of hypomeron, and metaventrite lacking any trace of the femoral lines. Morphology of its genitalia (see Hebauer 2002a, Fig. 22 ) also do not correspond with the Pachysternum species, but largely agree with those illustrated by Hansen (2003, Figs. 18–21 ) for the species of the Australocyon pilocnemoides group. For that reason, the species is transferred here to the genus Australocyon .

Australocyon keralensis may be diagnosed as follows: dorsal surface uniformly dark brown; antennal club unicolored; pronotum without sublateral depressions; posterolateral corners of pronotum bluntly rounded; pronotal punctation moderately coarse but sparse, consisting of punctures of two slightly different sizes; pronotal interstices bearing strong mesh-like microsculpture; elytra evenly convex, not humpy in humeral areas. Based on the key provided by Hansen (2003), the species seems to be very similar especially to A. pilocnemoides Hansen, 2003 and A. puncticollis Hansen, 2003 .

Figures

FIGURES 12 – 25. General morphology of the Asian Pachysternum. 12 – 14: pronotal punctation (12: P. nigrovittatum, 13: P. haemorrhoum, 14: P. r u g o s u m); 15: meso- and metathorax of P. nigrovittatum, ventral view; 16 – 19: preepisternal elevation of mesothorax (16: P. haemorrhoum, 17: P. s u l a w e s i c u m, 18: P. apicatum, 19: P. rugosum); 20 – 21: surface sculpture of metaventrite mesally and laterally of femoral line (20: P. nigrovittatum, 21: P. haemorrhoum); 22: elytral punctation of P. nigrovittatum; 23: scutellum of P. nigrovittatum; 24: anterior leg of P. nigrovittatum; 25: abdomen of P. nigrovitattum.