Medon

Assing, V., 2011, The Sunius species of the Palaearctic region (Coleoptera: Staphylinidae: Paederinae), Linzer biologische Beiträge 43 (1), pp. 151-193 : 189-191

" Medon " ghumensis CAMERON 1943 ( Figs 78-83 )

Medon (Hypomedon) ghumensis CAMERON 1943: 35 .

Sunius ghumensis: SMETANA (2004) .

T y p e m a t e r i a l e x a m i n e d Holotype: "Type / Ghum district, v-vi-31, Dr. Cameron / Fungus / M. ghumensis Cam. Type / M.Cameron Bequest B.M. 1955-147. / Syntype / Holotypus Medon ghumensis Cameron , rev. V. Assing 2010 / " Medon " ghumensis Cameron , det. V. Assing 2010 " (BMNH). Paratypes: 2: Ghum district, v-vi-31, Dr. Cameron / M.Cameron Bequest B.M. 1955-147. / Syntype / Syntype Medon ghumensis Cameron 1943 , det. R.G. Booth 2010 / Paratypus Medon ghumensis Cameron , rev. V. Assing 2010 / " Medon " ghumensis Cameron , det. V. Assing 2010 " (BMNH).

C o m m e n t: In stating "Type in my collection" CAMERON (1943) explicitly designated a holotype. Consequently, despite the syntype labels attached to the above material, the specimen with Cameron´s type label has holotype status and the two other females represent a paratypes. The species is listed as Sunius in the recent Palaearctic catalogue ( SMETANA 2004).

An examination of the external characters and the mouthparts of the type material revealed that the species does not belong to Sunius , as can be inferred particularly from the different shape of the labrum and the different morphology of the labium. Although it is probably not congeneric with true Medon either, it is temporarily attributed to this genus, which already includes numerous species of doubtful generic assignment.

R e d e s c r i p t i o n: Body length 4.2-4.8 mm. Habitus as in Fig. 78 . Coloration: Head dark-brown; pronotum reddish to dark-brown; elytra brown with the anterior portion diffusely and more or less extensively yellowish to yellowish-brown; abdomen reddish to reddish-brown, with the preapical segments sometimes somewhat infuscate; legs and antennae reddish-yellow to reddish.

Head ( Fig. 79 ) 1.05-1.10 times as long as wide; posterior angles moderately marked; punctation moderately fine and moderately dense, somewhat sparser in median dorsal portion; interstices without microsculpture, narrower than, or approximately as wide as diameter of punctures ( Fig. 80 ). Eyes relatively small and weakly protruding from lateral contours of head, approximately half as long as postocular portion or nearly so. Labrum transverse, anterior margin deeply incised in the middle, on either side of this incision with two tooth-like processes and an additional lateral process, mediad of this lateral process deeply sinuate ( Fig. 81 ); maxillary palpus similar to that of " M." fungi; ligula bilobed, without stout seta ( Fig. 82 ); left mandible with two, right mandible with three molar teeth ( Fig. 81 ). Gular sutures relatively broadly separated. Antenna of similar morphology as in Sunius species.

Pronotum ( Fig. 79 ) 1.05-1.10 times as wide as long and approximately 0.9 times as wide as head, weakly tapering posteriad; posterior angles weakly marked; punctation similar to that of head, but on average shallower; midline narrowly impunctate; interstices without microsculpture ( Fig. 83 ).

Elytra approximately 1.1 times as long and 1.20-1.25 times as wide as pronotum, moderately convex in cross-section; lateral margins weakly convex in dorsal view ( Fig. 79 ); punctation relatively fine, shallow, and rather ill-defined; interstices glossy. Hind wings apparently fully developed. Tarsi short; metatarsus approximately 0.6-0.7 times as long as metatibia. Metatarsomere I relatively short, slightly longer than II.

Abdomen approximately as wide as elytra, widest at segment VI; punctation very fine, relatively dense on anterior tergites and somewhat sparser on posterior tergites; interstices with shallow microsculpture and rather glossy; posterior margin of tergite VII with palisade fringe.

: unknown.

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: The known distribution is confined to the environs of Ghum in West Bengal, northeastern India. The type specimens were collected from fungi during the period May-June.

Figures

Figs 78-83: "Medon" ghumensis CAMERON: (78) habitus; (79) forebody; (80) median dorsal portion of head; (81) labrum and right mandible; (82) ligula; (83) median dorsal portion of pronotum. Scale bars: 78: 1.0 mm; 79: 0.5 mm; 80, 83: 0.2 mm; 81-82: 0.1 mm.