Pterorthochaetes tsurui Ballerio & Maruyama 2010

Description. HL = 0.69 mm; HW = 1.44 mm; PL = 1.38 mm; PW = 2.33 mm; EL = 2.36 mm; EW = 2.27 mm. Medium sized Pterorthochaetes, surface shiny, setose; “rolling up” coaptations perfect; volant. Dorsum brown, setation yellowish, sternum reddish, antennae reddish.
Head: subrectangular, wider than long, fore margin irregularly sinuated, serrated, tip acute, interocular distance about 9 times the maximum width of dorsal ocular area, dorsal ocular area large, sculpure distally made of very coarse and deep wrinkles and proximally of impressed small dense horseshoe-shaped punctures, each one having a pore in the middle bearing an erect simple seta.
Pronotum: wider than long (W/L ratio= 1.68), fore angles normally shaped, elytral lateral margins fringed with a row of long simple setae, spaced out by an interval about half of their length, the whole pronotal surface covered by medium sized round, shallow, ocellate punctures, each one having a pore in the middle bearing a long simple erect seta; puncturation relatively dense, the distance between punctures being inferior to their diameter, denser on disc and at sides, only at sides the ocellate punctures are replaced by horseshoe-shaped punctures with openings outwards. Pronotal pubescence relatively long, approximately as long as marginal setae.
Scutellum: punctures horseshoe-shaped, thick and coarse.
Elytra: shape oval, longer than wide (W/L ratio= 0.96); elytral surface covered by medium sized shallow horseshoe-shaped punctures with opening directed backwards, spaced out by an interval inferior to their diameter. Each horseshoe-shaped puncture containing a pore bearing a long erect simple seta.
Male genitalia: parameres about as long as basal piece, slightly asymmetrical (Fig. 7A, B), apex distinctly bent, internal sac armed with longitudinal subrectangular sclerotization about as long as the basal piece with three short distal sclerites (Fig. 7D), genital segment with manubrium long but strongly bent/twisted, so that in dorsal view it appears very short (Fig. 7E).
Female genitalia: bursal sclerites weakly sclerotized and shaped as in Fig. 7C.
Identification. This species is characterized by the following combination of characters: a) pronotal puncturation made of ocellate, shallow, medium sized punctures, b) lateral margins of pronotum fringed by long, simple setae, setae relatively spaced out, c) elytral puncturation made of medium sized horseshoe-shaped punctures with opening backwards and bearing a long erect seta, d) shape of parameres (about as long as basal piece and with bent apex, e) shape of genital segment of males, with manubrium strongly twisted, f) shape of female bursal sclerites and, g) head subrectangular, with fore margin somewhat sinuated in a way very unusual for Pterorthochaetes. Perhaps the species closest to it could be Pterorthochaetes brevisetosus, which, however, has pronotal and elytral puncturation much less dense and shorter setae.

Distribution and habitat. This new species is know only from the type locality. For details on collecting circumstances see the introductory paragraphs.