282 R. W. CROSSKEY 



obvious before - for example the very definite selection by Chaetexorista of hosts 

 in the Limacodidae, by Eozenillia of hosts in the Psychidae, by Thecocarcelia of 

 hosts in the Hesperiidae, by Zygobothria of hosts in the Sphingidae, and by Goniini 

 of hosts in the Noctuidae. 



Although particular tachinid genera and species tend to favour a particular 

 host or host group there are very few instances in the Oriental fauna of strict host 

 specificity, i.e. confinement of one tachinid species to one host species, and apparent 

 cases of this are almost certainly due simply to lack of knowledge. The great 

 majority of host-parasite associations that must exist between Tachinidae and 

 other insects in the Oriental Region remain unknown, and those that are known 

 (listed in the accompanying host catalogue) are a somewhat biased sample - know- 

 ledge of them being derived largely from the fact that the hosts are economic pests 

 or belong to the Macrolepidoptera (a group that has a wide collectorship). 



Many of the major or minor insect pests of the Oriental Region have tachinid 

 parasites that can be regularly reared from them and that presumably play some 

 part in regulating their numbers. The food-plants of the hosts in such associations 

 include agricultural crops such as sugar, rice, cotton and coconut, or forest timbers 

 such as teak, and the most important hosts are lepidopterous. The hosts include 

 for example, the sugarcane borer (Chilo sacchariphagus) that is parasitized by 

 Diatraeophaga striatalis, the rice stem-borers Sesamia inferens and Chilo suppressalis 

 that are parasitized by Sturmiopsis inferens, the cotton bollworm Heliothis armigera 

 that is parasitized by a variety of goniine tachinids, the coconut caterpillar Nephantis 

 serinopa that is parasitized by Stomatomyia bezziana, the teak wood-borer Xyleutes 

 ceramica that is parasitized by Cossidophaga atkinsoni, and the teak defoliators 

 Hyblaea puera and Pyrausta machoeralis that are attacked by many species of 

 Goniinae. Non-lepidopterous pests in south-east Asia that have tachinid parasites 

 include melolonthine beetles, the larvae of which are attacked by Prosena siberita 

 and the adults by Palpostoma incongruum. 



Several species of Neotropical Tachinidae have been introduced into the Oriental 

 Region for the attempted biological control of stem-borers, especially those attacking 

 rice and sugarcane. Lixophaga diatraeae (Townsend) has been released in Formosa, 

 India and Philippines, M etagonistylum minense Townsend in Formosa, India and 

 Malaysia, and Paratheresia claripaipis (Wulp) in Formosa, India and Malaysia, 

 but none has become established. Kamran (1973) reviews the 'dismal record' 

 of attempts to introduce Neotropical tachinids against graminaceous stem-borers 

 in south-east Asia. [See also Appendix, p. 337.] 



Similarly, attempts have been made to introduce Oriental Tachinidae into other 

 regions for the biological control of sugarcane borers, but so far there appear to 

 be no cases of successful establishment. Bennett (1965) discusses the shipment 

 of Diatraeophaga striatalis and Sturmiopsis inferens to Trinidad, and Ghani (1962) 

 records an attempt to establish D. striatalis in Mauritius. On the other hand, 

 the introduction of the Oriental tachinid Bessa remota (i.e. Ptychomyia remota) 

 from Malaya to Fiji for the control of the coconut moth Levuana iridescens Bethune- 

 Baker was resoundingly successful and is now a much-quoted classic of biological 

 control (see DeBach, 1974 : 124-128). 



