Ptecticus semimetallicus, Rozkošný, Rudolf & Hauser, Martin, 2009

Rozkošný, Rudolf & Hauser, Martin, 2009, Species groups of Oriental Ptecticus Loew including descriptions of ten new species with a revised identification key to the Oriental species (Diptera: Stratiomyidae), Zootaxa 2034, pp. 1-30 : 14-15

Ptecticus semimetallicus sp. nov.

( Figs 31–33 )

Type material. Holotype, female, NEPAL. Katmandu, Godavari, 6000 ft, 31.vii.1967, Canadian Nepal Expedition, in CNC. Paratypes, 2 females, with same locality label but dates 14.vii and 30.vii.1967, ( CNC).

Etymology. The specific name refers to the unusual metallic pattern on the scutum, which may demonstrate intermediate species between australis and longipennis group.

Diagnosis. A species from the australis group differing from the related species by the position of vein R2+3 that starts slightly beyond crossvein R-M and a subquadrate metallic green patch in the middle of the prescutellar area; also central part of the scutellum metallic green. The hind tibia and more than basal half of the hind basitarsus are black and black haired.

Description. Female. Head semiglobular, deeply concave posteriorly. Upper frons, vertex and entire occiput black. Frontal vitta band-shaped, almost parallel-sided, slightly dilated in front of ocellar tubercle, distinctly broader than ocellar triangle, frontal index 3.8–4.0. Frontal callus prominent and rounded, about as high as distal end of fore tibia is broad, contrastingly white though more yellowish on lower surface. Antenna ochre yellow, basal antennal segments shining, scape about 1.5 times as long as broad, pedicel only narrow on outer surface and with usual subtriangular projection on inner side. Flagellar complex matt and rounded but transverse cut at distal margin, with dark arista placed in upper corner. Face, proboscis and palpus pale yellow. Head pile mostly erect, as long as scape and black, partly yellowish only below antennae, entirely yellow on proboscis and lower postocular area. Short hairs on lower surface of frontal callus brownish and pile of both basal antennal segments blackish.

Thorax shining yellowish brown, pleura paler but katatergite and mediotergite nearly brown. Subquadrate medial area in front of scutellum and extensive central patch on scutellum dark, metallic green. Postpronotal callus, a narrow subnotopleural stripe and postalar callus more yellow. Thoracic pile pale yellow to white, erect and almost as long as on frons especially on anterior half of scutum and mediotergite, even longer on propleuron and katatergite, shorter on rest of pleuron and scutellum, anepisternum extensively bare.

Wing membrane almost hyaline, veins dark brown to black, pterostigma yellow. Vein R2+3 starting distinctly beyond crossvein R-M, about 1.8 times as long as Rs, both radial veins converging but well separated at costal margin. Radial triangle (r2+3) thus low, barely higher than crossvein R-M is long, crossvein M-Cu very short but distinct. M3 straight, parallel to M2, its missing apical part much longer than crossvein R- M, postcubitus (CuP) unpigmented. Halteres brownish, only basal half of stem yellow. Hairs on posttegula pale yellow.

Legs yellow including all coxae, only hind tibia and more than basal half of hind basitarsus black and black haired. Last tarsomere of fore and mid legs darkened, nearly brown. Leg pile predominantly yellow, mostly short and appressed, only on posteroventral surface of mid femur longer and erect. Short black hairs (in addition to the black parts of hind legs) also visible on distal four tarsomeres of fore leg, last tarsomere of mid leg and hind femur. Distal haf of hind basitarsus and all following tarsomeres with snow white pile.

Abdomen yellow with black broad transverse bands dorsally. Black bands reaching lateral margins of tergites, leaving only very narrow anterior margin and broader posterior margin of tergites yellow. Yellow posterior part of tergites 2 and 3 may reach 1/3 of tergite length. Apical tergites beginning from segment 6 black, rarely yellowish laterally, last tergite between cerci yellowish. Sternites predominantly yellow, differently darkened at base and apex of abdomen. Dark parts of abdomen with a distinct bronze sheen. Abdominal pile mostly short and appressed, black on dark parts and yellow on pale parts, longer yellowish and erect hairs distinct on tergite 1 and along lateral margin of segments becoming shorter caudad, also black hairs on abdominal apex somewhat longer and semi-erect to erect.

Female terminalia ( Figs 31–33 ) with relatively short and stout black cerci. Basal segment of cercus cylindrical, barely 4 times as long as broad and apical segment somewhat shorter, more spindle-shaped. Proctiger deeply emarginated posteroventrally, tergite 9 replaced by two lateral sclerites, genital furca speciesspecific, with well defined round middle aperture.

Length: body 9.4–11.0 mm, wing 9.0– 10.8 mm.

Male. Unknown.

Remarks. P. semimetallicus sp. nov. is based on the female holotype and two female paratypes. The definitive species group cannot be proposed because the male terminalia could not be examined. Nevertheless, the wing venation confirms the relation to the australis or longipennis species groups though the origin of R2+3 slightly beyond crossvein R-M is rather unusual. On the other hand the bronze sheen of the abdomen is well known in some members of the australis group (e.g. P. vulpianus ).

Figures

FIGURES 31 – 33. Ptecticus semimetallicus sp. nov., female terminalia in dorsal view (31), ventral view (32) and genital furca (33). Scale: 0.5 mm.