Tachydromia carnarvonensis, Grootaert, 2011

Grootaert, Patrick, 2011, The Genus Tachydromia Meigen (Diptera: Hybotidae) from Australia, Records of the Australian Museum 63 (1), pp. 103-112 : 107-108

Tachydromia carnarvonensis n.sp.

Fig. 3

Type material. HOLOTYPE ♂, Australia, Queensland, Carnarvon Nat. Pk, Mt. Moffat Sect. E. branch Maranoa River, nr. Top Moffat Cmp (25°03.2'S 148°03.5'E), 10–11.x.2002, J.M. Cumming, PT [ QMB].

Diagnosis. This species can be readily recognized among Australian congeners by a short subapical seta on the palpus and largely shining thorax with prothoracic sclerites (including anterior part of postpronotal lobe) densely silvery grey pollinose.

Description. Male length 2.0 mm; wing 1.9 mm. Head black in ground-colour, with black setation. Eyes with posterior margin slightly produced beyond ocellar tubercle; vertex broader than frons in front of ocellar tubercle. Occiput almost entirely shining, with narrow space of fine pollinosity between vertex and neck; vertex entirely shining; 2 inclinate, long, black postvertical setae, some setae around neck and near mouth-opening and row of minute postoculars. Ocellar tubercle shining, with 2 short lateroclinate setae. Frons shining, slightly widened toward ocellar tubercle, above antennae 2.0–2.5 times broader than anterior ocellus. Antenna brownish. Postpedicel elongate oval, short, with somewhat long subapical brownish stylus which is about 3.0 times as long as pedicel and postpedicel combined. Palpus unmodified, slender, pointed, nearly as long as proboscis, brownish; lacking silvery setae, with some scattered black setulae and bearing moderately long (somewhat shorter than palpus) black apical seta. Thorax black in ground-colour, almost entirely shining; prothoracic sclerites (including anterior part of postpronotal lobe) densely silvery grey pollinose, scutellum, metanotum and hypopleuron greyish pollinose. Postpronotal lobe large, lacking conspicuous setae. Mesonotum with 1 notopleural [missing], 1 moderately long black postalar and 2 similar scutellar setae; some minute setulae present behind postpronotal lobe; mesosternum and metasternum bare between posterior four coxae. Acrostichals lacking. Dorsocentrals partly missing, arranged in 1 row, mostly minute (including prescutellars), at least one pair on middle part strong. Legs long, slender, almost entirely brownish; fore and hind coxae (except extreme base), trochanters, fore and mid femora on extreme base and apex, hind femur on about basal 1/5 and tibia on extreme base yellowish; fore tarsomeres 1–3 yellowish, tarsomeres 4–5 brown, mid and hind tarsomeres becoming gradually darker from tarsomere 1 (almost entirely yellowish) to tarsomere 5. Coxae mostly with short pale hair-like setae, bearing some longer and stronger setae apically; fore coxa anteriorly, mid and hind coxae laterally silvery grey pollinose. Fore femur slightly thickened, pale pubescent ventrally, with minute dark anteroventral and posteroventral setulae longer basally. Fore tibia slightly spindle-shaped. Mid femur slender, with rows of anteroventral and posteroventral setae stronger on apical half of the femur. Mid tibia with hardly prominent subapical projection, bearing black ventral spinule-like setulae. Hind leg unmodified, lacking prominent setae. Wing normally developed, rounded at apex, with unmodified venation; two broad brown bands connected on cells r 1 and r 2+3 leaving narrow basal, apical and median hyaline spaces. One short costal bristle present. Vein R 2+3 slightly arched about middle toward costa. Veins R 4+5 and M 1+2 parallel toward wing-apex. Crossveins r-m and bm-cu separated. Calypter pale coloured and fringed. Halter whitish. Abdomen entirely blackish brown; tergites subshining, finely greyish pollinose, sternites shining; with scattered minute dark setulae. Terminalia ( Fig. 3 ) rather large, elongate oval, blackish brown. Right cercus rather short, subrectangular, with several setae of different lengths and bearing 5 short subapical spines on inner side. Left cercus hardly prominent, with minute setulae. Right epandrial lamella subrectangular, covered with numerous setae of different length, lacking ventral process. Right surstylus hardly differentiated from epandrium, broad, rather long, slightly curved inward, with numerous moderately long subapical setae and several spines on inner side. Left surstylus differentiated from epandrium, bilobed; upper lobe broad, rather long, with several setae of different length; lower lobe small, with several short setae. Hypandrium humped basally, lacking setae. Phallus elongate.

Female. Unknown.

Etymology. The epithet refers to Carnarvon National Park where the new species was collected.

Distribution. This species is currently recorded from a single locality in Queensland, taken in the beginning of October.

Remarks. Tachydromia carnarvonensis n.sp. is very similar to T. papuana described from Papua New Guinea ( Grootaert, 1987). The main distinguishing characters between these species are given in the key.

Figures

Fig. 3. Tachydromia carnarvonensis: (a)right surstylus, dorsal; (b) terminalia, dorsal; (c) left epandrial lamella and left surstylus, lateral. Scale 0.1 mm.