Bengalia subnitida James, 1964

Rognes, Knut, 2018, Revision of the Bengalia torosa Wiedemann, 1819 species-group (Diptera: Calliphoridae), with notes on the systematic position of B. robertsi Kurahashi, 1987 and B. subnitida James, 1964, Zootaxa 4391 (1), pp. 1-71 : 65-67

Bengalia subnitida James, 1964

( Figs 263–270 )

Bengalia subnitida James, 1964: 172 . HoloType ♂ ( NHMUK; examined), by original designaTion. Type localiTy: Nepal ( Taplejung Distr , below Sangu).

Bengalia subnitida: James (1977: 530; catalogue entry) .

Bengalia subnitida: Kurahashi & Thapa (1994: 218) ( Nepal; several males and females).

Type material examined. HOLOTYPE ♂ (NHMUK), labelled (1) Holo- / type [printed on circular white label with a red rim]; (2) TAPLEJUNG DISTR., / below Sangu. / By stream in / shady ravine. / c 6000' 30.x.1961. [printed]; (3) BRIT. MUS. / East Nepal Exp. / 1961-62. / R.L.Coe Coll. / B.M.1962-177 [printed]; (4) Bengalia / subnitida / ♂ / James / HOLOTYPE [handwritten by James on red label except two last lines, which are printed] [Right mid leg lost; right hind leg glued to stage; right wing broken at base and detached, glued to a card on a separate pin with copy of original labels; lower half of anepimeron with pale and black setulae; upper half with setulae black; abdomen black; ST5 flap roughly as in the NSMT males, but see Descriptive notes, below]. PARATYPE ♀ (NHMUK), labelled (1) Allo / Type [first line handwritten, second line printed, on white circular label with a red rim]; (2) [text as in holotype]; (3) [text as in holotype]; (4) Bengalia / subnitida / ♀ James / ALLOTYPE [handwritten by James on red label] [Sternites all yellow, with a pair of marginal setae; right wing and both mid legs lost]. [Both specimens staged on long polyporus strips; no discal setae on T 5 in either of the two specimens.]

Other material examined. NSMT. Nepal: 2 ♂, labelled (1) NEPAL / Phedi / Pokhara / 28 July 1992 / R. Kano [printed]; (2) Bengalia ♂ / subnitida / James, 1964 / Det. H. Kurahashi [printed] ( Fig. 263 ) [One “greased” male dissected by me, the other male not “greased”]; • 2 ♂, labelled (1) NEPAL: Gandaki / Kaski, Chandrakot / - Phedi, 1640 - / 1215m, 16.X.1990 / Col. H. Kurahashi [printed]; (2) Bengalia ♂ / subnitida / James, 1964 / Det. H. Kurahashi [printed] [Both “greased”].

Descriptive notes. Length. 13.0mm (n=3). Frons at vertex / head width ratio 0.33–0.35 (mean 0.34, n=4). Thorax. Greater ampulla oval. Anepimeron with black setulae in upper half and with many pale and a few black setulae in lower half, the black ones hardly reaching katepisternum. Legs. All tibiae fringed posteroventrally, the hind tibia also anteroventrally, ventrally and posteroventrally. Abdomen. Very dark, black and white microtrichose in shifting pattern, with yellow background colour showing through only at base of T1+2 ( Fig. 270 ). T5 lacking discal setae, though one of the males from Gandaki has a single discal seta on T5. ST5 flap. Distal bay rather deep and narrow ( Figs 265–266 ), deeper and much narrower than in B. emarginata Malloch ( Rognes 2009b, figs 12, 15, 19, 23). Small lateral bays ( Fig. 266 ) similar to those of B. emarginata . James’s (1964, fig. 39) figure of the ST5 flap in the holotype is a little different. The distal bay in the holotype is somewhat deeper in the actual specimen (ST5 flap in situ) than in James’s drawing, but not as deep as in the dissected NSMT male. Distal bay also more Vshaped and not as evenly curved as in B. emarginata . The ST5 flap is very different from the one in B. emarginatoides Rognes (Rognes 2009, figs 35, 37–38, 40, 42). Distiphallus. In the dissected NSMT specimen the left surstylus was absent ( Fig. 264 ). The distiphallus ( Figs 267–269 ) is very similar to that of B. emarginatoides , viz. (1) distal edge of upper lip (ul) slightly convex ( Fig. 269 ); (2) anterior serrate edge of lateral wall straight ( Fig. 268 , lower arrow); (3) antler with two small processes distally ( Fig. 267 , arrow); (4) lateral wall between lateral end of upper lip and base of antler oblique and almost straight in lateral view, different from B. emarginata Malloch ( Fig. 268 , upper arrow); (5) lateral finger (lf) reaching beyond outer edge of lateral hypophallic lobes in ventral view ( Fig. 269 ); (6) cercus similar to but not as narrow as in emarginatoides ; also with a relatively abrupt narrowing towards long prongs in dorsal view ( Fig. 264 ) (for comparisons, see Rognes 2009b, figs 26–28, 33).

Discussion. This species, like Bengalia robertsi , lacks discal setae on T5 (though one of the four NSMT males has a single discal seta on T5). Even though described by James (1964), it was not placed to species-group by him.

The structure of the distiphallus shows beyond doubt that B. subnitida belongs in the Bengalia peuhi Villeneuve species-group (see Rognes 2009b). Bengalia emarginata , B. emarginatoides and B. subnitida form a group of closely related species within that species-group. The dark colour and lack of discal setae on T5 are diagnostic for B. subnitida . The ST5 flap of B. emarginatoides is different from those of B. marginata and B. subnitida . Bengalia emarginata (with discal setae on T5) occurs in Nepal together with B. subnitida . Bengalia emarginatoides (also with discal setae on T5) occurs only in South India and Sri Lanka ( Rognes 2009b). The frons measurements in B. subnitida agree with those in B. emarginata (see Rognes 2009b).

Figures

FIGURES 263–270. Bengalia subnitida James (male from Phedi, Pokhara, Nepal, NSMT). 263. Labels. 264. Epandrial complex, posterior view (left surstylus lost). 265. Tip of degreased abdomen with ST5 flap in situ, ventral view. 266. ST5 flap. 267. Phallus, left lateral view; arrow showing tip of antler. 268. Detail of apical part of distiphallus, left lateral view. Arrows pointing to important details. 269. Distiphallus, ventral view. 270. Degreased abdomen on card pinned with dissected specimen, dorsal view. All scale bars = 0.25mm. Abbreviations: lf = lateral finger; ul = upper lip.