Enlarged-hind-femora
Guides
Chalcididae
Chalcidid Wasps
Chalcididae is a family of parasitoid wasps within the superfamily Chalcidoidea, comprising over 85 genera and more than 1,460 species worldwide. Members are characterized by greatly enlarged, toothed hind femora that enable powerful jumping. Most species are parasitoids of Lepidoptera and Diptera pupae, though some attack Coleoptera (particularly jewel beetles in the genus Chrysobothris) and other insects. The family is currently considered polyphyletic, with subfamilies potentially warranting elevation to family status. They occur across diverse habitats from tropical to temperate regions, with notable diversity in semiarid regions of Brazil and teak plantations in Southeast Asia.
Chalcosyrphus nemorum
Dusky-banded Leafwalker
Chalcosyrphus nemorum is a common species of syrphid fly with a Palearctic and Nearctic distribution. Adults are medium-sized hoverflies with distinctive enlarged, swollen hind femora bearing ventral spines and curved hind tibiae—adaptations associated with their association with dead wood. The species exhibits sexual dimorphism, with males having holoptic (contiguous) eyes. Larvae develop under the bark of conifers (Larix, Pinus) and various hardwoods, where they function as saprophages in decaying wood. Adults are flower visitors, obtaining nectar and pollen from diverse plant species including white umbellifers, Caltha, Anemone nemorosa, and Ranunculus.