DEVELOPMENT OF TIPHODYTES GERRIPHAGUS (HYMENOPTERA: SCELIONIDAE) IN LIMNOPORUS DISSORTIS EGGS (HEMIPTERA: GERRIDAE)
AbstractInvestigations of preimaginal development in Tiphodytes gerriphagus Marchal reveal two larval instars, based on counting exuviae and comparing mandible length during development within Limnoporus dissortis Drake & Harris eggs. Tiphodytes gerriphagus eggs are stalked, as is typical of scelionids, and are 282.6 ± 3.48 μm (mean ± SE) long. The chorion ruptures at 8–9 h postoviposition and releases a nonfeeding embryo into the host. Feeding begins at 18–20 h postoviposition, after the embryonic cuticle is shed and a fully differentiated and active larva is released. The first larval stage is teleaform and lasted up to 5 days postoviposition, and its total length increased from 183.6 ± 3.35 to 517.0 ± 14.67 μm. The second larval stage is hymenopteriform and lasted from 5 to 13 days postoviposition, and grew from 920.2 ± 24.65 to 1352.4 ± 11.89 μm total length before pupating. The pupal period lasted about 11 days, with male pupae being shorter and thinner than female pupae. These findings differ from previous descriptions of T. gerriphagus, and it is suspected that the first instar was mistakenly divided into two stadia. The sex ratio under laboratory conditions was female biased (22% males), and males were smaller but did not emerge significantly earlier than females.