TACHINIDAE OF AUSTRALIA 63 



[The Eurasian and African genus Steiniomyia Townsend runs here and has all 

 the essential characters of Hyleorus. It should be treated as a synonym of the 

 latter, but definite synonymy is not established at this time] 

 Prosternum bare. Eyes bare or almost completely so. M 2 spur vein or fold short, 

 not nearly as long as the section of M between m—cu and the bend (Text-fig. 82). 

 One or both intermediate abdominal tergites without discal setae. Facial ridges 

 bare (except for the usual very few setulae immediately above the vibrissae) 



HYSTRICOVORIA Townsend 



[The Ethiopian and Oriental genus Afrovoria Curran (synonym A navoria 

 Mesnil) runs here and has all the essential characters of Hystricovoria. It should 

 probably be treated as a synonym of the latter, but definite synonymy is not 

 established at this time] 



Tribe THELAIRINI 



This is a small but widely distributed tribe occurring in both Old and New Worlds. 

 The type-genus Thelaira is found throughout the Palaearctic and Oriental Regions, 

 Africa and Madagascar, in New Guinea and in eastern Australia south to Tasmania, 

 and in the New World occurs southwards as far as Mexico; in the Pacific area the 

 genus is apparently unrepresented eastwards of New Guinea. The only genus found 

 so far in Australia, other than Thelaira, is Halydaia, a very distinctive form occurring 

 in most of the Oriental Region eastwards to Japan, the Ryukyu Islands, New 

 Guinea, the Solomons and Australia (excluding Tasmania) ; at least one rare species 

 of Halydaia occurs also in western Europe. In the Old World Halydaia appears 

 to be rather disjunct from other thelairines, but the genus appears to be rather 

 closely related to the Neotropical genus Xanthodexia Wulp (syn. Minthodexia 

 Brauer & Bergenstamm) which is somewhat intermediate between Halydaia and 

 the more typical Thelairini. 



The chief characteristics of the Thelairini are as follows. Eyes bare or virtually so (some 

 very minute hairs can sometimes be made out under high power examination) ; parafacials 

 bare; eyes extremely large and filling most of the sides of the head, gena correspondingly 

 very reduced and without a definite genal dilation (eyes coming so far down on the head 

 that the lowest point is usually below the level of the vibrissae) ; face and epistome fiat, latter 

 invisible in profile; vibrissae usually level with epistomal margin (above the level in the 

 Oriental genus Proshellomyia Brauer & Bergenstamm) ; antennae small or very small (length 

 less than half of eye-height) and antennal axis at or below level of eye middle; arista usually 

 short plumose or long plumose, sometimes pubescent; proboscis very short, mentum convex 

 on lower edge in profile, palpi well developed (a little flattened) ; prosternum, prosternal 

 membrane, and propleuron bare; two sternopleural setae (rarely three in g) ; 3 + 3 dc setae; 

 pre-alar seta very small ; two or three post ia setae (rarely specimens may have only one) ; 

 infrasquamal hairs usually absent; scutellum with three pairs of very strong marginal setae 

 (basals, subapicals, and strong crossed horizontal apicals) ; pteropleural seta absent (except 

 in Prosheliomyia in which weak pteropleural always evident) ; fore coxa largely bare or fully 

 haired on inner anterior surface; mid tibia with a v seta; hind coxa bare posterodorsally; 

 hind tibia without a pv apical seta; upper surface of wing setulose at least on R i+i half way 

 to r-m, often veins R 1 and Cu 1 extensively setulose (R 1 setulose along all its length in both 

 genera occurring in Australia); cell i? 5 open to the wing margin; bend of vein M moderately 

 sharp or rather evenly rounded, usually without M 2 appendix; second costal sector haired 

 ventrally; excavation of Ti + 2 variable, usually not quite reaching hind margin of tergite; 



