Pterodontia Gray, 1832

Winterton, Shaun L., 2012, Review of Australasian spider flies (Diptera, Acroceridae) with a revision of Panops Lamarck, ZooKeys 172, pp. 7-75 : 58-63

Pterodontia Gray, 1832 Figs 3D65-66

Pterodontia Gray, 1832: 779 - Macquart 1838: 174; Erichson 1840: 161; Walker 1855: 346; Westwood 1876: 513; White 1914: 68; Hardy 1921: 76, 1946: 66; Paramonov 1957: 529; Schlinger 1959: 158. Type species: Pterodontia flavipes Gray, 1832: 779 by monotypy.

Nothra Westwood, 1876: 514 - Hardy 1921: 77, 1946: 66. Type species: Nothra bicolor Westwood, 1876: 514 by monotypy.

Note.

Synonymy and usage list restricted to Australasian region fauna only.

Diagnosis.

Body length: 3.0-7.0 mm [male], 4.0-10.0 mm [female]. Body shape not arched. Body colouration non-metallic; head much narrower than thorax width; shape nearly spherical; postocular ridge and occiput rounded; three ocelli; posterior margin of eye rounded; eye pilose (dense); antennae located adjacent to mouthparts; eyes contiguous above antennal base, not contiguous below antennal base; palpus absent; proboscis greatly reduced; flagellum stylate, apex with terminal setae (multiple); antenotum shape not collar-like behind head; subscutellum not enlarged, barely visible; tibial spines present; pulvilli present; wing markings absent; costa circumambient; wing costal margin straight or with anterior projection (males); humeral crossvein present or reduced; radial veins curved or angled towards wing anterior margin; R1 inflated distally at pterostigma (especially in male); pterostigma and cell r1 membranous, not ribbed; R2+3 present; R4+5 present as single vein; basal cell r4+5 (portion basal to bisecting 2r-m) merged with discal cell to form composite cell comprising d+r4+5; cell m3 absent; medial vein compliment usually a single M vein fused with CuA1, petiolate to margin, sometimes with second medial vein originating from cell d+r4+5; CuA2 fused to A1 before wing margin, petiolate, rarely open to wing margin; wing microtrichia absent; anal lobe well developed; alula present or absent, rarely well developed; abdominal tergites smooth, rounded; abdomen shape greatly rounded, inflated.

Included species.

Pterodontia davisi Paramonov, 1957; Pterodontia longisquama Sabrosky, 1947; Pterodontia mellii Erichson 1840 (= Pterodontia variegata White, 1914 syn. n.).

Key to Australasian Pterodontia species

Comments.

Pterodontia is a cosmopolitan genus containing 19 valid species, three of which are recorded from the Australasian region ( Schlinger and Jefferies 1989). Pterodontia variegata was described by White (1914) and differentiated from Pterodontia melli (as Pterodontia macquarti Westwood, 1848) based on colouration of the fore femur, scutellum and abdomen. Paramonov (1957) examined a range of specimens from various localities and suggested that the former was likely a synonym of the latter. Based on examinations of these and additional specimens this synonymy is supported herein.

Some species of Pterodontia have greatly enlarged and sclerotized lower calypters, appearing somewhat like a second pair of wings (e.g. Pterodontia davisi ). Males in this genus typically have sclerotized projections on the costal margin of the wing. Characteristics which diagnose this genus from other acrocerids include head very small relative to thorax width, tibial spines present, cells m3, d and basal r4+5 fused to form a single cell, eyes densely pilose, antennae adjacent to the ocellar tubercle and mouthparts reduced. Contrary to other authors, Pterodontia has been placed previously in Panopinae by Schlinger (1981, 1987, 1989) based on the presence of tibial spines. The wing venation of Pterodontia is unique among acrocerids.