A new family and genus of acalypterate flies from the Neotropical region, with a phylogenetic analysis of Carnoidea family relationships (Diptera, Schizophora)

The acalypterate family Inbiomyiidae fam.n. (Diptera, Carnoidea) is described for the newly discovered Neotropical genus Inbiomyiagen.n. with its type species I. mcalpineorumsp.n. from Costa Rica. The genus ranges from Guatemala south to French Guiana and Bolivia and includes a total of fourteen undescribed species, ten of which will be described formally in a separate paper. Inbiomyia is distinctive, with characteristic, extremely shortened head with nonfunctional ptilinum and reduced chaetotaxy, shortened first flagellomere with very elongate, dorsoapically inserted arista, proboscis with largely separate labellar lobes that point in different directions, mid tibia lacking apicoventral bristle, unusual fusion of male sternites 5-7, reduced male sternite 8, elongate surstyluslike ventral epandrial lobes, cerci absent in both sexes, extremely truncate female genitalia, and large, extremely flattened eggs. The larva of Inbiomyia and its biology are unknown. Inbiomyia occurs mostly in primary lowland rain forest and often is associated with the decaying foliage of fallen trees. Inbiomyiidae belong in the superfamily Carnoidea. The previously doubtful monophyly of the Carnoidea is accepted tentatively on the basis of newly established synapomorphies of the male genitalia. Family level relationships of the Carnoidea are analysed quantitatively for the first time based on a matrix of fifty-eight morphological characters. The putative sister group relationship of Inbiomyiidae to the monotypic Australasian family Australimyzidae is supported by several synapomorphies, mostly from the male and female postabdomen. Family status for the Australimyzidae is confirmed, rejecting previous claims of a sister group relationship (or synonymy) with the Carnidae. The analysis also leads to revised hypotheses of the relationships of Cryptochetidae and Acartophthalmidae, and the paraphyly of 'Tethinidae' with regard to Canacidae, suspected by previous authors, is confirmed.