Ptecticus bannapensis, 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 : 4-6

Ptecticus bannapensis sp. nov.

( Figs 4–7 )

Type material. Holotype, male, LAOS: Bolikhamsai Province, Ban Nape environs, 18°20´N, 105°08´E, 400– 100 m a.s.l., 7–16.v.2004, E. Jendek & O. Šauša, in ZIB.

Etymology. The name of this species indicates the type locality (Ban Nape) in Laos where the unique male was collected.

Diagnosis. A larger species from the histrio -group with a yellowish brown upper frons, vertex and median occipital sclerite. The thorax is yellowish brown, without dark, broad, longitudinal stripes. The legs are predominantly yellow, only the hind tibia and the last three tarsomeres on all legs are blackish. The male terminalia and especially the aedeagal complex are asymmetrical.

Description. Male. Head almost semiglobular in lateral view, only slightly narrowed ventrally in profile, ocellar triangle distinctly prominent, frontal callus arched but barely as high as width of fore tibia in the middle. Majority of head yellowish brown including median occipital sclerite, only ocellar tubercle and rest of occiput black. Upper frons gradually tapering towards frontal callus, about as broad as anterior ocellus at narrowest point. Frontal callus somewhat paler, almost drop-like, with a fine longitudical medial groove, face and proboscis also yellowish brown. Antenna concolourous with face, both basal segments indistinctly darker, shining, inner finger-like extension of pedicel well developed, flagellar complex laterally somewhat depressed, longer than high, suboval but more pointed at base of arista, arista dark brown. Head pubescence inconspicuous, uniformly yellow, more brownish only on postocular area. Basal antennal segments covered with dense short yellowish brown hairs.

Thorax uniformly pale brown, pleura more yellow, scutum without broad longitudinal vittae as in other species of group. Thoracic pubescence short and appressed to semi-erect, golden yellow on scutum and scutellum, more yellowish on pleura, longer and erect only on propleuron and katatergite.

Wing membrane uniformly tinged with pale brown, stronger veins, costal cell and pterostigma yellow, weaker veins brown. Crossvein R-M very slightly beyond origin of R2+3, radial triangle (r2+3) not as high as half length of crossvein R-M, R2+3 converging to R1 and touching it at wing margin..Upper proximal part of discal cell distinctly arched, crossvein M-Cu short but distinct. Vein M3 markedly sinuate, its short apical part (barely equalling length of crossvein M-Cu) missing. Postcubitus (CuP) distinct, almost as strong as cubital vein in basal part, yellow. Halter pale but its knob black. Posttegula with short black hairs.

Fore and mid legs pale yellow, only their last three tarsomeres deeply black and black haired, pubescence on femora and tibiae very short, mostly appressed and golden yellow, only on ventral surface of tarsomeres very dense and more erect. Hind coxa, trochanter and femur yellow and again with short golden yellow pile, hind tibia black and black haired except for both ends which are with dense golden yellow hairs distinct distally up to beginning of distal third on ventral as well as dorsal surface. Last three tarsomeres again black and black haired but also tarsomere 2 darkened and black haired dorsally. Ventral dense fringe of hind tarsomeres golden yellow.

Abdomen yellow, with relatively reduced black transverse bands on tergites 2–5, all of them ending far before lateral margins of tergites, only very narrow and interrupted medianly on tergites 2 and 3. Broader transverse bands on tergites 4 and 5 occupying slightly more than medial third of tergites and with a distinct medial incision at posterior margin. All sternites yellow to yellowish brown. Abdominal pubescence generally short and appressed, predominantly golden yellow but black on dark spots. Longer and erect yellow hairs distinct only on sides of abdominal segment 1.

Male terminalia ( Figs 4–7 ) yellow and short yellow haired, only gonostylus with long, black hairs. All parts distinctly asymmetrical. Proctiger and cerci rather long, cerci longer than proctiger and subpointed apically, epandrium longer that wide, with a semicircular proximal emargination. Genital capsule long and somewhat constricted at middle, asymmetrically dilated proximally. Gonostylus elongate and rounded apically, with a beak-like projection on lower inner side. Aedeagal complex highly asymmetrical, S-shaped in lateral view, more slender than in related species, with distinctly reduced left distal part and mainly black medially and distally. Length: body 17.6 mm, wing 15.5 mm.

Female. Unknown.

Remarks. The wing venation and structures of the male terminalia confirm an evident relationship to the other members of the histrio group though the typical broad longitudinal vittae on the scutum are absent. Likewise as in P. brevipennis and P. pangmapensis the abdomen is not spatulate but slender, spindle-shaped. The shape of gonostylus resembles P. proximus but the epandrium and the genital capsule are much longer and the aedeagal complex is quite different.

Figures

FIGURES 4 – 7. Ptecticus bannapensis sp. nov., male terminalia. 4, lateral view. 5, epandrium, proctiger and cerci. 6, genital capsule and gonostyli. 7, aedeagal complex. Scale: 1.0 mm.