Haematobosca aberrans, Duvallet & Changbunjong, 2020

Pont, Adrian C, Duvallet, Gérard & Changbunjong, Tanasak, 2020, A new species of Haematobosca Bezzi (Diptera: Muscidae) from Thailand, Zootaxa 4763 (4), pp. 538-544 : 539-542

Haematobosca aberrans sp. nov.

( Figs 1–7 )

Diagnosis. Among the species with the palpus about as long as proboscis and grooved internally, the new species can be recognised by the absence of the anterior katepisternal seta together with arista plumose (not pectinate), and proepisternal depression, meron and prosternum bare.

Etymology. The name indicates the aberrant feature of this species, namely the absence of the anterior katepisternal seta.

Type Material Examined. Holotype ♂. THAILAND: Chiang Mai Province, Mae Wang district , N18°38’58.48’’ - E98°31’44.93’’, Nzi trap, 12.iii.2018, T. Changbunjong, in BMNH . Paratypes 2♂ 3♀. THAILAND: Data as for the holotype, in VSMU.

Description. Male. Head ( Figs 1–2 ). Ground-colour black. Eye bare; posterior eye-margin concave at middle. Frons narrow ( Fig. 1 ), at narrowest point almost 3 times diameter of anterior ocellus. Fronto-orbital plate and parafacial silvery pruinose, gena and lower half of occiput whitish-grey pruinose. Fronto-orbital plates separated throughout by a distinct frontal vitta which at narrowest point is slightly narrower than diameter of anterior ocellus. Ocellar setae minute, fine, hardly distinct from adjacent setulae. 8–10 pairs of frontal setae, in a row from ocellar tubercle to lunule, all except the lowest pair proclinate. Antenna black; postpedicel barely twice as long as broad in lateral view. Arista with very long plumes dorsally and ventrally, bare on basal third ventrally. Gena linear, with short fine setae on margin. Palpus yellow, brownish near tip ( Fig. 2 ). Proboscis dark brown, shining.

Thorax ( Figs 4–5 ). Ground-colour black. Scutum densely yellowish-grey dusted with a pair of broad black vittae running from neck to the middle of the scutum and laterally to postalar callus ( Fig. 4 ), each vitta briefly divided with a narrow indistinct brown line; also with a median brownish line postsuturally that impinges on to base of the yellowish-grey dusted scutellum. Pleura yellowish-grey dusted. Spiracles brownish-yellow. Setae: acrostichals 0+1; dorsocentrals setulose, only 1 presutural and 2 prescutellar pairs detectable, only the last prescutellar pair well-developed; intra-alars 0+1; supra-alars 1+1; prealar absent; only 1 strong postpronotal; 2 postalars. Postalar wall and suprasquamal ridge bare. Notopleuron with 2 setae, each with several adjacent setulae. Prosternum bare. Proepisternal depression bare. Anepisternum with a fine seta in upper anterior corner. Anepimeron setulose on subalar sclerite and below. Katepisternal setae 0+1, the anterior one replaced by 1–2 tiny fine setulae ( Fig. 5 ). Katepimeron and meron bare. Posterior spiracle without setae on posterior margin. Katatergite pilose. Anatergite bare. Scutellum with apical, lateral and subbasal lateral setae; disc sparsely setulose; lateral margin and ventral surface bare.

Legs. Coxae and trochanters black. Femora black, yellow at tips. Tibiae black, yellow on basal third or more. Tarsi black. Fore tibia without submedian setae. Mid femur with only setulae on ventral surfaces; with a row of setae on basal half of anterior surface; 0 anterior and 1 posterior preapical seta, preceded by a series of short setae on apical half of femur. Mid tibia without submedian setae. Hind femur with 1 ventral seta near base and 1 anteroventral just before apex. Hind tibia without setae on the shaft, but the row of anterodorsal setulae well-developed; 1 dorsal but 0 anterodorsal preapical seta. Tarsi without setae or long hairs, but hind tarsomere 1 with a short anteroventral seta near base.

Wing. Clear. Vein M bowed evenly towards vein R4+ 5 in apical half, and cell r4+5 at apex as broad as length of cross-vein r-m ( Fig. 6 ). Veins bare, including base of R4+5. Calypters yellowish-white, the margins more smoky yellow. Haltere yellow.

Abdomen. Ground-colour black. Tergites densely yellowish-grey dusted with black markings as follows ( Fig. 7 ): syntergite 1+2 with a transverse crescent-shaped band; tergite 3 with a pair of large quadrate spots occupying the length of the tergite and with a broad black vitta on the dusted area separating them; tergite 4 with a pair of dark brown oval spots at middle of tergite and a black vitta on the dusted area separating them; tergite 5 unmarked. Sternite 1 setulose laterally. Terminalia not examined.

M easurements. Wing-length, 3.5 mm. Body-length 4.0 mm.

Female. Differs from the male as follows:

Head. Frons broad ( Fig. 3 ), at middle 0.38 of greatest head-width in frontal view. Fronto-orbital plate and parafacial grey pruinose. Fronto-orbital plate at middle not much narrower than frontal vitta and with convex margins. Frontal triangle indistinct, narrow, grey, reaching lunule. Ocellar setae very short, setulose. 1 pair of frontal setae at lunule, and above this with 3 short frontal setae and 3 setulose exclinate orbital setae ( Fig. 3 ). Frontal vitta without setae. Palpus brown in apical part.

Thorax. The dark pattern reduced to absent before suture; after suture as in male but not so dark and therefore not so contrasting with the dusted areas.

Legs. Hind femur with the posteroventral seta near base shorter and finer.

Wing. Calypters and margins wholly creamy-white.

Abdomen. Dark pattern reduced, with the dark spots smaller and the dark vitta on the dusted area separating them shorter and narrower. Terminalia not examined.

Measurements. Wing-length, 3.0 mm. Body-length, 3.5 mm.

Figures

FIGURES 1–4. Haematobosca aberrans sp. nov. 1, Male head, in frontal view (holotype). 2, Male head, in lateral view (holotype). 3, Female frons, in dorsal view (paratype). 4, Male scutum, viewed from above and behind (holotype).

FIGURES 5–7. Haematobosca aberrans sp. nov. 5, Male pleura (holotype). 6, Male right wing (holotype). 7, Male abdomen, viewed from above and behind (holotype).