Enhancing identification of the genus Melanagromyza from California (Diptera: Agromyzidae)

Agromyzids are phytophagous flies that, as leaf-miners on California specialty crops, can be potential pests. The genus Melanagromyza is the second largest genus of the subfamily Agromyzinae, distributed worldwide, with 70 described species in the Nearctic Region, of which 34 are known in the USA. For California, there are 24 described and 4 new species, which feed on 36 host plants present in the state. The species of the genus Melanagromyza are black and shiny metallic, and are often confused with some species of the genus Ophiomyia. Based on examined materials from CDFA, EMEC, CAS, UCD and USNM, 26 diagnostic characters of adults can be used to distinguish among the 28 species of California. Photographs of characters by scanning electron microscopy and light microscopy are given. Comparing characters of some species of the two genera Melanagromyza and Ophiomyia that are difficult to separate, five comparative characters are analyzed. A Lucid interactive identification key, combined with morphological descriptions, photographs, host plant data, distribution and literature is discussed.

Keywords: Lucid key, Melanagromyza, Agromyzidae, California