Ophiomyia centrosematis (De Meijere, 1940)
O. centrosematis is closely related and very similar to the European Ophiomyia orbiculata but there is no overlap in distribution. In the currently known limits of distribution the male genitalia are reliable for identification of centrosematis.
IMPORTANT CHARACTERS
Adults
Wing length: 1.7 - 2 mm.
Male terminalia
Aedeagus with basiphallus and distiphallus broad, terminal tubules conspicuous.
Immature stages
The larvae and puparia can be distinguished from Ophiomyia phaseoli and Ophiomyia spencerella, which frequently occur on the same plant, by the shape of the anterior and posterior spiracles. In Ophiomyia centrosematis the anterior spiracles are distinctly elongated which normally projecting through epidermis of the host plant during pupal stage. The posterior spiracles consist of only three bulbs whereas in phaseoli and most other Ophiomyia species their number is higher.
BIONOMICS
This species lives mainly as external stem miner like Ophiomyia phaseoli. On some host plants the larvae cause apparently mines in the pod cover (Sehgal, 1965). In these case the eggs are probably laid into the pods.
Normally, oviposition takes place in stems or hypocotyles, one female lays 45-85 eggs (Talekar, 1990). On soybeans, the duration of the larval development ranges from 7-20 days (Talekar and Lee, 1988). Pupation occurs in the cortex of the stem and lasts 7-27 days. The developmental time is strongly affected by the temperature, e.g. at 20°C the larval development took 20 days whereas at 35 the larvae were fully grown in only 8 days (Talekar, 1990).
HOST PLANTS
The species lives in various wild and cultivated fabacean crops. This list of host plants based on various literature references was taken from Talekar, 1990. Cajanus cajan, Calopogonium mucunoides, Centrosema pubescens, Coccina indica, Crotalaria mucronata, Dolichos fiflorus, Glycine max, Lablab niger, Medicago denticulata, Medicago sativa, Phaseolus angularis, Phaseolus lunatus, Phaseolus vulgaris, Pisum sativum, Tephrosia candida, Tephrosia vogelli, Vigna angularis, Vigna marina, Vigna mungo, Vigna radiata, Vigna unguiculata. The original host plant from which the species was described is Centrosema pubescens.
The main host plants appear to be soybean (Glycine max), limabean (Phaseolus lunatus), snapbean (Phaseolus vulgaris) and adzuki bean (Phaseolus angularis).
DISTRIBUTION
Australia, China (Fujyan), India, Indonesia, Japan, Kenya, Malaysia, Micronesia, Taiwan, Tanzania, Thailand, Uganda.
ECONOMIC IMPORTANCE
Ophiomyia centrosematis occur on most fabacean crops that were also infested by phaseoli and in Africa by spencerella. It is generally assumed, that centrosematis is less important than the first mentioned species (Talekar, 1990).
In certain localities in northern India the species is considered as significant pest on the garden pea (Pisum sativum L.) (Singh et al., 1981).
In Java and Malaya centrosematis may cause damage on Centrosema pubescens and Calopogonium mucunoides, which are cover plants of rubber plantations (de Meijere, 1940).