Scientists discover new parasitoid wasp in Western Ghats

Bengaluru: A study by entomologists of the Ashoka Trust for Research in Ecology and the Environment (ATREE) in Bengaluru has reported the discovery of a new wasp species in Karnataka.

Taeniogonalos deepaki was discovered from the Western Ghats, in the Nipani region of Belagavi. The genus Taeniogonalos belongs to the family Trigonalyidae of the order Hymenoptera; the Trigonalyidae family consists of a type of insects called hyperparasitoids that “sneak into” parasitoids, or insects whose larvae develop on or within the bodies of other insects.

The Taeniogonalos genus is distributed in Afrotropical, oriental, eastern palaearctic, nearctic, Australian and neotropical regions; 6 of the species have been reported earlier from India and 20 from China. In their diagnosis, the scientists report a combination of characters including head, antenna, and fore-wing that makes the new species different from the other Taeniogonalos species in India.

Taeniogonalos deepaki is named after the medical doctor and nature enthusiast Dr Deepak Deshpande who collected the specimen. The study, conducted by ATREE scientists Femi Ezhuthupallickal Benny, A P Ranjith and Priyadarsanan Dharma Rajan, was published in the latest issue of the international journal Zootaxa.

The scientists have also reported the first male description of another species, Taeniogonalos eurysoma. The female of the species was described from China in 2020. Ranjith collected the male from Arunachal Pradesh. The paper notes that occurrence of the T. eurysoma male from Arunachal Pradesh indicates a “possible overlap” of the fauna between India and China.

“The discovery from Arunachal Pradesh is important since most of the Taeniogonalos species have been reported from south India. Extensive taxonomic studies that cover wider areas could establish the presence of more species,” Femi told DH.

A parasite of parasites

A hyperparasitoid parasitises the larvae of primary parasitoids. A case in point is a hyperparasitoid from the Trigonalyidae family that lays eggs that end up getting eaten by caterpillars. If the caterpillar is already hosting another parasitoid, the Trigonalyidae larvae will take over and grow by attacking the parasitoid larvae.

If the caterpillar is not hosting any parasitoid larvae, and if the caterpillar gets eaten by a wasp larva, the Trigonalyidae will target the wasp larva instead. If none of this happens, the Trigonalyidae larvae cannot grow.