H2 R. W. CROSSKEY 



with excavation of Ti + 2 not reaching beyond the middle of the tergite and with 



a pair of erect median marginal setae on T3 . . PHYTOMYPTERA Rondan 



Tribe SIPHONINI 

 (Actiini) 



The Siphonini are a worldwide group of unusually small Tachinidae that mainly 

 attack the larvae of smaller Lepidoptera; some species of Siphona Meigen apparently 

 also parasitize the leatherjacket larvae of crane-flies (Tipulidae) but there are no 

 Oriental records of such a habit. In the Oriental Region the tribe is very richly 

 developed, and many species have been described from the area, particularly by 

 Malloch and Mesnil. There are some doubts, however, as to how many of these 

 supposed species are taxonomically valid and the group badly requires a full revision; 

 it is not justified to continue describing so-called new species from the area when 

 we still have insufficient idea as to how many of those already described are to be 

 considered valid and what characters are dependable for their separation. Many 

 of the Siphonini have the wing veins very extensively setulose on both upper and 

 lower surfaces, and differences in the distribution of setulae along the veins (e.g. 

 whether present or absent on vein C% and whether present on the whole of R 1 

 or only on the apical part) have been widely used as specific characters in the tribe, 

 but it is questionable whether such characters are as dependable as they first appear: 

 it would be of interest and value to investigate whether differences in distribution 

 of the wing setulae correlate with differences in male terminalia. 



Up to now the Siphonini have generally been regarded as a segregate within 

 the subfamily Goniinae, but Herting (personal communication) believes that they 

 would be better placed in the Tachininae. The tribe is here retained in its traditional 

 position within the Goniinae, where it can be easily recognized by possessing the 

 following characters. 



Head form not sexually dimorphic, frons of equal width in £ and 9. both sexes with outer 

 vertical setae and proclinate orbital setae. Pre-alar seta minute. Scutellum with very strong 

 convergent subapical setae that almost meet or cross at the apices. Wings short and broad, 

 costal margin conspicuously incised at apex of vein 5c, vein M with bend very gently and 

 evenly curved and very remote from the wing margin (apical section of M completely obliterated 

 in some forms); veins more extensively setulose than is usual in Goniinae, R t often partly or 

 wholly setulose, Cu 1 (fifth vein) also often setulose. Legs rather short and with stiff setae, 

 mid tibia never with more than one ad seta in Oriental forms, hind tibia with three strong 

 d preapical setae (i.e. a pd preapical present in addition to the usual ad and d preapicals). Abdo- 

 men with Ti + 2 excavate only on its basal half, all tergites lacking discal setae. 



Four genera are recognized as occurring in the Oriental Region, all of which are 

 found widely in other zoogeographical regions. They may be distinguished by the 

 key that follows. 



Key to Oriental Genera of SIPHONINI 



1 Proboscis very long and slender, geniculate and capable of being 'doubled back' in 

 the resting position, total length greater than the height of the head and the 

 labellae very long and thin (Text-fig. 52) .... SIPHONA Meigen 



