Denon silvestris, Bordoni, 2017

Bordoni, Arnaldo, 2017, New data on the Oriental Xantholinini. 43. New species and new records from Thailand in the Naturhistorisches Museum of Basel (Coleoptera Staphylinidae) 281 ° contribution to the knowledge of the Staphylinidae, Linzer biologische Beiträge 49 (2), pp. 1219-1229 : 1223-1224

Denon silvestris nov.sp.

( Figs 10-12 , photo 2)

Examined material: Holotype ♂: W Thailand, Tak prov., Mae Wong Nat. Park , 600 m, Li 15.IV.2001 ( cB).

Description: Length of body 4.2 mm; from anterior margin of head to posterior margin of elytra: 2.3 mm. Body (photo 2) shiny, amaranth with lighter elytra and abdomen; antennae and legs brown light. Head sub-rectangular, slightly dilated posteriad, with sub-parallel and sub-rectilinear sides and largely rounded posterior angles. Eyes medium-sized and a little protruding. Surface of head with evident and sparse punctation. Pronotum longer and anteriorly a little narrower than head, dilated forward, with oblique anterior margins, largely rounded anterior angles and sinuate sides. Surface with dorsal series of 5 fine and spaced punctures and lateral series of 3 very fine punctures. Elytra long, sub-rectangular, not dilated posteriad, longer and wider than pronotum in its widest point, with sub-rectilinear and sub-parallel sides and marked humeral angles. Surface with three series of very fine punctures, one juxtasutural, one median and one lateral. Abdomen with traces of fine, transverse micro-striation and fine, sparse punctation.

Tergite and sternite of the male genital segment as in Figs 10-11 . Aedeagus ( Fig. 12 ) 0.77 mm long, ovoid elongated, with thick, short parameres; inner sac tape-like, covered with fine and very dense spinulae.

Etymology: The specific epithet is the Latin silvestris- e (sylvan).

Distribution: The species is known only from the type locality.

Remarks: The genus Denon BORDONI, 2002 was described for a species (D. silvaticus BORDONI, 2002) from South central Thailand (Nakhon Nayok prov., Ban Na) and it is characterized by the following characters: upper epipleural line of pronotum present only in the proximal and distal portions and therefore not joint with the lower line; by the long and deep frontal grooves, by the prosternum with rectilinear posterior margin and very reduced intercoxal apophysis, and by the shape of the aedeagaus (cfr Figs 1412-1422 in BORDONI 2002).

Until now I do not see other specimens of this genus. The collection of a new species is evidently of great interest. The genus seems actually present only in Thailand.

The new species differs from D. sylvaticus by the following characters: head more narrow and long, less dilated posteriad, with more dense punctation; eyes a little larger; pronotum longer and less dilated forward; elytra evidently sub-rectangular, narrower, not dilated posteriad; aedeagus a little longer (0.77/ 0.74 mm), with different parameres and inner sac.

Figures

Figs 10-15: Tergite and sternite of the male genital segment and aedeagus (10-12) of Denon silvestris nov.sp., Male genital segment, sternite of the same and aedeagus (13-15) of Indolinus inermis nov.sp. (scale bar: 0.1 mm).