TACHINIDAE OF ORIENTAL REGION 19 



that - at least on present evidence and as currently understood - do not occur 

 outside the Oriental Region, but the other five genera are shared with other zoo- 

 geographical regions. 



The shared genera comprise two, viz. Pentatomophaga de Meijere and Besserioides 

 Curran, that are Oriento-Australasian, and three that are very widespread in 

 several zoogeographical regions, viz. Alophora Robineau-Desvoidy s.l. (which some 

 authors consider should be called Phasia Latreille), Ectophasia Townsend (Phasia of 

 many authors), and Gymnosoma Meigen. These should be considered in more 

 detail. 



As pointed out previously (Crosskey, 19736 : 32) the genus Pentatomophaga is 

 virtually impossible to distinguish from the Ethiopian genus Bogosia Rondani, 

 and in my opinion probably ought to be synonymized with it. However, I refrain 

 from formally establishing this synonymy because it is better left to a specialist 

 undertaking a comprehensive revisionary study of phasiine genera (when it may 

 well be found that not only should Pentatomophaga be synonymized with Bogosia 

 but also with Ectophasia, the oldest name Bogosia then coming into use for a much 

 widened generic concept and applying to forms in several extra-Ethiopian regions 

 as well as to African forms). (Here I note in passing my view that nowhere in 

 the Tachinidae has generic splitting reached more ludicrous proportions than in the 

 Phasiini. Even a casual inspection of the Phasiini is sufficient to show that many 

 of the so-called generic characters that are used in the group are of the most trivial 

 kind and do not work satisfactorily when the world fauna is considered in toto. 

 At present excessive splitting is serving only to obscure the interrelationships of 

 the fauna.) 



The genus Besserioides has hitherto only been recorded from Australia but speci- 

 mens of a specifically undeterminable species near to the Australian B. varicolor 

 (Curran) are in the BMNH collection from India and Ceylon. A similar problem 

 of generic limits and geographical range exists with this genus as with Pentato- 

 mophaga, since Besserioides shows obvious affinities with the tropical African 

 genus Bogosiella Villeneuve and could well be united with it on a redefined basis. 

 Besserioides differs from Bogosiella by having prolonged posterior puparial spiracles 

 and the frons broad in both sexes but it is questionable whether these features 

 justify generic separateness. As with Pentatomophaga it is here retained as valid 

 pending full-scale revision of genera on an inter-regional basis. 



The genus Gymnosoma is mainly Holarctic and African, but occurs more widely 

 than has been generally realized in the Oriental Region; it seems, however, to be 

 totally absent from Australasia. The distribution in the Oriental area is unusual 

 because Gymnosoma occurs in the Philippines, but is apparently absent from most 

 of the south-east Asian mainland and from Malaysia and Indonesia. In general 

 in the Oriental area the genus occurs across the northern borders, and is best known 

 from Pakistan and northern India, but the northerly Oriental range includes Formosa 

 and it seems likely than Gymnosoma reached the Philippines by a trans-Formosan 

 route. (The same route might account for the unexpected presence in the Philip- 

 pines of some other 'northerly' genera, e.g. Periscepsia Gistl in the Wagneriini.) 



The remaining two genera, Alophora s.l. and Ectophasia, are still poorly known 



