Tetrastichus howardi (Olliff) (Hymenoptera:Eulophidae), a Hyperparasitoid of Tachinid Natural Enemies of Helicoverpa armigera (Hubner) (Lepidoptera:Noctuidae) in India

Tetrastichus howardi (Olliff) was found to be a hyperparasitoid of the tachinids Goniophthalmus halli (Mesnil) and Senometopia (= Eucarcelia) illota (Curran) parasitising Helicoverpa armigera (Hubner) pupae in pigeonpea fields in South India. Fifty nine per cent of G. halli and S. illota pupae were parasitized by T. howardi resulting in a hyperparasitism rate of 1.9 per cent. Unlike previous studies, T. howardi was not recorded as a primary parasitoid of H. armigera pupae. Rather than behaving as a pupal guild parasitoid, the data suggest that T. howardi wasps oviposit in the larval stage of the tachinid parasitoids while they are developing inside the H. armigera pupa. The fact that T. howardi was not found to be a primary parasitoid of H. armigera pupae, suggests that this species is able to distinguish between parasitised and unparasitised H. armigera pupae.