Morphological and molecular techniques for the differentiation of myiasis-causing Sarcophagidae

Each year myiasis maggots are submitted for identification at the USDA National Veterinary Services Laboratories from infested host animals. Although most of these maggots are identified to species, an absence of adequate descriptions for maggots in the flesh fly family (Sarcophagidae), makes species-level identifications difficult, if not impossible for those specimens. In a survey of entomological literature, a preliminary list of 19 species of sarcophagid flies implicated in myiasis was narrowed to what are probably the seven most important species in North America north of Mexico; those species are Bercaea africa, Gigantotheca plinthopyga, Liopygia argyrostoma, L. crassipalpis, Neobellieria bullata, N. citellivora, and Wohlfahrtia vigil. Detailed descriptions of third-instar maggots were made for six of the seven species (i.e., those for which specimens could be obtained). Using characters in these descriptions, a dichotomous key was made for the identification of the six species. Also, DNA sequence data from the cytochrome oxidase subunit I gene were obtained from five of the seven species and compared to existing sequences in online databases. All of these data will help with the specific identification of sarcophagid maggots found in cases of myiasis in North America north of Mexico