Systematics and taxonomy of the ant parasitoid Kapala (Eucharitidae: Hymenoptera)

Eucharitidae (Chalcidoidea) contains 54 genera and over 475 described species. Kapala is a commonly-collected genus in the New World. It is part of the ‘Kapala Clade’, which is a monophyletic group of 14 Neotropical genera that is supported in both morphological and molecular analyses. However, the relationships of the genera within the clade are not easily resolved. There is a large amount of variation across the group, although most of the genera of the Kapala Clade are easy to distinguish from one another based on their scutellar spine morphologies. Morphology has been less successful, however, in determining robust sister-group relationships among the genera. In many cases, molecules provide crucial information for group relationships and morphological character interpretation. For comparison with morphological hypothesis, we use a molecular dataset of five gene regions (18S, 28S D2 & D3-5, COI, and COII) to determine relationships of Kapala Clade genera, with a focus on Kapala. Kapala is a genus of special interest, since it is easily recognized and is the most geographically widespread of the genera, though there are no morphological synapomorphies to support it. Any study involving Kapala necessarily includes all genera of the Kapala Clade because molecular evidence suggests this genus is polyphyletic and spans the phylogenetic distance of the Kapala Clade. We conclude that morphology is important for identification and is needed for diagnostic description, but there are some groups, such as this one, where molecules may need to take a primary role in the phylogeny-building process.