The genus Aphrastomyia Coher & Lane, 1949 in Costa Rica (Insecta: Diptera: Mycetophilidae)

The genus Aphrastomyia Coher & Lane, 1949 is shown to be present in Costa Rica with seven species, which are described as new to science: A. biocellata sp. n., A. brevicornis sp. n., A. communis sp. n., A. flavicornis sp. n., A. longirostris sp. n., A. quadrilineata sp. n., and A. solitaria sp. n. Based on new information on the adult morphology in these species, the description of the genus is supplemented. Even though two infrageneric lineages are recognisable, Aphrastomyia is shown to be a systematic entity quite distinct from other mycetophilid genera. Its peculiar morphology is discussed in a phylogenetic context. A key to the Costa Rican species of Aphrastomyia is given.