Abstract
BACKGROUND: A new species, Dendrocerus scutellaris Trietsch & Mikó (Hymenoptera: Megaspilidae), is described here from male and female specimens captured in Costa Rica. This species is the only known ceraphronoid wasp with a straight mandibular surface and raised dorsal projections on the scutellum, called the mesoscutellar comb. It is hypothesised that the function of the mesoscutellar comb is to aid the emergence of the adult from the host, especially since the mandibles lack a pointed surface to tear open the pupal case. The authors also provide phenotypic data in a semantic form to facilitate data integration and accessibility across taxa and provide an updated phenotype bank of morphological characters for megaspilid taxonomic treatments. In updating this phenotype bank, the authors continue to make taxonomic data accessible to future systematic efforts focusing on Ceraphronoidea. NEW INFORMATION: A new species, Dendrocerus scutellaris (Hymenoptera: Megaspilidae) Trietsch & Mikó, is described from both male and female specimens captured in Costa Rica.