Pristapenesia asiatica Azevedo, Xu et Beaver

Azevedo, Celso O., Xu, Zaifu & Beaver, Roger A., 2011, A new species of Pristapenesia Brues (Hymenoptera, Scolebythidae) from Asia, Zootaxa 2750, pp. 60-64 : 61-63

Pristapenesia asiatica Azevedo, Xu et Beaver , sp. nov.

( Figs 1–6 )

Material examined. Holotype FEMALE: Thailand, Loei, Pha Nok Khao For[est] St[atio]n, Malaise trap, semievergreen forest, [16º47'N 101º57'E], 7–9.II.2010, R. Beaver, L-Y.Liu. ( BMNH). Paratype female: [ China], Shaanxi, Xianyang, 1978, [sweeping], Yang Huai-yu ( SCAU). Holotype condition: specimen complete and in good condition. Paratype condition: Ten apical flagellomeres of left antenna missing, eight apical flagellomeres of right antenna missing, tips of both fore wings missing, last tarsomere of right hind leg missing; mesoscutum broken; prosternum and mesosternum disrupted.

Diagnosis. Female. Mandible with four sharp apical teeth. Clypeus with angulate median lobe, median carina absent. Head slightly narrower anteriorly. Frons weakly coriaceous and with sparse punctures. Malar space broad. Posterior ocelli distant from vertex crest. Vertex rounded. Occipital carina weak, present only ventrally. Pronotal disc very short. Notauli absent. Parapsidal furrow weak. Mesoscutellum long. Metanotum very short medially. Propodeal disc without anterior, median and discal carinae. Prosternum very large. Fore wing ( Fig. 4 ) without tubular Rs vein; Cu vein present as very short stub. Hind wing with basal hamuli absent, with four median hamuli. Legs not spinose. Pretarsal claws simple.

Description. Holotype female. Length of body 5.4 mm; LFW 2.55 mm.

Color ( Figs. 5–6 ). Body mostly evenly dark castaneous, head, pronotum and mesonotum darker, palpi, tarsi lighter; wings subhyaline, veins and pterostigma dark castaneous.

Pubescence. Sparse and long overall, but shorter on antenna and anterior half of metasomal terga, sparser on ventral surface and dorsum of head, mesosomal nota and metasomal terga, [almost absent on ventral propleuron, prosternum and mesosternum,] and denser on antenna and posterior half of metasomal sterna.

Head ( Fig. 1 ). Mandible wholly slightly ventrad, overlapping opposite one about 25% of its length, with four sharp apical teeth, and with shallow sulcus below upper tooth, ventral tooth larger than dorsal one. Clypeus extremely short, median lobe angulate in dorsal view, without median carina, but slightly elevated medially. Antenna appearing short, first four antennal segments in ratio of about 17:12:4.5:6, scape flattened in cross-section, flagellomere 1 as long as wide, flagellomeres 2 and 3 slightly longer than wide. Head slightly narrower anteriorly. Antennal sockets separated from each other by slightly less than their own diameters. Frons slightly elevated above clypeus, with longitudinal line very narrow, inconspicuous between anterior elevation and anterior ocellus; weakly coriaceous, with very few small and shallow punctures; frontal carina absent. Malar space broad, about 1.0 × basal width of mandible. LH 1.16 × WH; WF 0.52 × WH; WF 0.94 × HE; ocellar triangle broad, surpassing imaginary upper tangent of compound eyes, its frontal angle obtuse, OOL 1.5 × WOT; posterior ocelli distant from vertex crest by 5.5 × DAO. Compound eye subtriangular, with rounded angles. Head widest across genae. Vertex rounded, VOL 0.72 × HE; sides of head almost straight, slightly converging anteriorly. Occipital carina weak, present only ventrally. Hypostomal carina evenly arched. Palpal formula 6:4, palpomeres flattened in cross-section.

Mesosoma ( Fig. 2 ). Weakly coriaceous, with very few punctures. Pronotal disc very short, 0.36 × length of mesoscutum; anterior margin of pronotum evenly convex in dorsal view. Notauli absent. Parapsidal furrow weak, narrow, nearly complete, paralleled by outer elevation. Mesoscutum and mesoscutellum separated from each other by narrow sulcus fairly deep medially, but shallower laterally. Mesoscutellum long, 1.1 × as long as mesoscutum, antero-lateral corner with shallow inclined groove. Metanotum very short medially. Propodeal disc 0.57 × as long as wide; anterior margin of propodeum without transverse carina, median and discal carinae absent; spiracle laterad, slit narrow and with elevated rim. Propodeal declivity without carinae, very short medially, with subhorizontal lamina projecting posterad, slightly covering metacoxa. Propleuron large, produced strongly forward. Prosternum very large, its width 2.1 × length of propleuron, and 0.95 × length of profemur, diamond-shaped, posterior margin slightly sinuous. Mesopleuron with deep scrobal pit above mid-height. Mesosternum with narrow and deep median longitudinal groove. Metasternum narrow, but separating base of mesocoxae.

Wings. Fore wing ( Fig. 4 ) about 2.8 × as long as its maximum width; dorsal surface not densely setose, setae on veins longer than those of on surface; anterior margin to point slightly beyond pterostigma and apical margins fringed, posterior margin not fringed; only costal, basal and first discal cells closed; costal cell narrow and longitudinally folded, partially visible in full dorsal view, median and submedian cell triangular; prostigma absent; pterostigma wide, 0.6 × as long as wide; Rs vein entirely spectral and progressively less pigmented distad; 1cu-a vein nearly vertical; Rs+M vein reaching Sc+R vein, far from pterostigma, about 0.5 × its length; Cu vein present as very short stub.

Hind wing with dorsal surface not densely setose; margins fringed, except apical two-thirds of anterior margin; costal vein 2.8 × as long as median vein, arched basally, anal lobe distinct; basal hamuli absent, with four equidistant median hamuli.

Legs. Weakly coriaceous, without spines. Procoxae very large, nearly touching each other medially, gibbous, subcircular in ventral view, only slightly longer than wide. Profemur 2.7 × as long as thick, ventral surface flat, so that transverse section is subtriangular, contrasting to elliptical section of meso- and metafemora. Metatibia about 1.2 × longer than metafemur. Metacoxae closely set. Metabasitarsus of very long, longer than one-half length of metatibia and longer than remaining metatarsomeres combined. Tibial spur formula 1:1:1. Pretarsal claws simple and arched, dilated basally, sharp apically.

Metasoma ( Fig. 3 ). Not petiolate, coriaceous, longer than both mesosoma and head together. Tergum 1 with anterior half declivitous, remaining area horizontal. Sternum 1 with median line sharply produced ventrad on anterior half.

Variations. A few differences between the two specimens are noted as follows: prosternum width is 1.0 × length of profemur; fore wing is about 2.4 × as long as its maximum width; costal vein is 2.6 × as long as median vein; and the tergum 1 with anterior half vertical, rather than declivitous.

MALE. Unknown.

Distribution. China (Shaanxi) and Thailand (Loei).

Etymology. Specific epithet is an adjective and refers to the continent where the species was found.

Remarks. The main diagnostic character of this new species is the absence of a tubular Rs in fore wing; instead there is a long faint impression of it. It can be identified with the following key to fossil and extant species of world Pristapenesia:

Figures

FIGURES 1 – 6. Pristapenesia asiatica sp. nov. 1, Head, dorsal view. 2, Mesosoma, dorsal view. 3, Metasoma, dorsal view. 4, Fore wing. 5, Habitus, dorsal view. 6, Habitus, lateral view.