Genus Porphyrochroa Melander

Porphyrochroa Melander, 1928: 137 . Type species: Sciodromia palliata Coquillett by original designation. Smith 1967: 29 (catalogue: synonym of Macrostomus). Rafael 2001: 130. Rafael & Ale-Rocha 2002: 241. Rafael & Cumming 2004: 439. Mendonça et al. 2007: 352.

The nominal genus Porphyrochroa has generally been overlooked since it was described by Melander (1928). Smith (1967) considered it a junior synonym of Macrostomus . Porphyrochroa was finally revalidated by Rafael (2001). In this paper, Rafael also transferred Axelempis fasciventris Curran to the genus.

Recognition: The monophyly of Porphyrochroa is based on the following hypothesized synapomorphies: 1) male tergite 8 with only a few setae confined posterolaterally; 2) male tergite 7 with posteroventral protuberances; 3) abdomen metallic blue or blue-green in colour.

Description: See Rafael and Cumming (2004) for redescription.

Remarks: The precise sister-group of the Macrostomus + Porphyrochroa lineage is not yet defined, but possibly is near species within the New World Rhamphomyia Meigen, a diverse polyphyletic genus with world wide distributuion.