New insights on the biology and larval morphology of Neotropical Mesostoinae (Hymenoptera, Braconidae): Hydrangeocola llaollin sp. nov. an endoparasitoid of Centrodiplosis crassipes (Diptera, Cecidomyiidae)

The Southern Hemisphere subfamily Mesostoinae (Hymenoptera: Braconidae) includes, in most cases, species associated with plant galls, although the details regarding their biological traits are largely unknown. In this contribution, Hydrangeocola llaollin sp. nov. is described based on specimens that develop as larval endoparasitoids of Centrodiplosis crassipes (Diptera: Cecidomyiidae) in stem galls on Lycium chilense (Solanaceae). The mature larva of a Neotropical mesostoine wasp is described here for the first time and is compared with the only known larva from Australia. Larval morphology is entirely congruent with features typical of endoparasitoid species, which together with male genital features clearly relates Hydrangeocola with the South American genus Andesipolis, but separates it from the Australian phytophagous genus Mesostoa. These findings reveal the relevance of larval and male genital characters for our comprehension of the relationships among representatives of this poorly known braconid subfamily.