Elasmus nephantidis Rohwer

Elasmus nephantidis parasitizes the pre-pupal stage, it is monophagous gregarious ectoparasitoid. It is well adapted to thrive during summer season, which is the peak period of 0pisina arenosella population.

For rearing this parasitoid one or two fully grown late last instar caterpillars of Opisina arenosella are placed in clean dry glass vial. When the host caterpillars start spinning silken cocoon (entering pre-pupal stage) 1-2 day old mated females of E. nephantidis @ 2-3 are released in each vial. The parasitoid readily deposits its eggs inside the host through silken cocoon one by one in groups after stinging and paralyzing it. Each female lays about 14-57 eggs. After egg laying the parasitoids are transferred to other glass vial containing appropriate stage of the host caterpillars. The tubes inoculated with Elasmus are kept upside down on the stand or rack to prevent the possible squeezing in of the parasitoids between the mouth of the glass tube and the cotton plug, as these parasitoids have a tendency to crawl up. The eggs hatch in about 20 hours, the larval period lasts 3.5 - 5 days and pupal period 6-5 days (Egg to adult 11 days). The newly hatched parasitoid larvae are very mobile, can locate the host body and are found all over the body. The developing larvae quickly feed from different points. All the larvae stop feeding more or less simultaneously. Freshly formed pupae are creamy, which soon change to light brown and then brown. Emergence of adults from a brood is completed within 1-3 hours. The females predominate, their population the culture is eleven times that of males.

From each host 50-60 adult parasitoids are obtained. For mass culturing of this parasitoid specimen jars (17.5 x 6.75 cm) containing prepupal stage of Opisina remaining inside the silken galleries can also be used.