Macrostomus ferrugineus (Fabricius, 1805), the type-species of Macrostomus Wiedemann, 1817 and Porphyrochroa palliata (Coquillett, 1902), the type-species of Porphyrochroa Melander, 1927 are redescribed and figured from the types. Both Neotropical genera are considered sistergroups and their synapomorphies are presented. The species belonging to both genera, and those Neotropical species remaining in the heterogeneous group Rhamphomyia Meigen, 1822 are listed. A key to genera is provided, 25 species are transferred to Porphyrochroa: P. abdominalis (Bezzi, 1905) comb. nov., P. argyrina (Bezzi, 1909) comb. nov., P. barueri (Smith, 1962) comb. nov., P. carrerai (Smith, 1962) comb. nov., P. catarinae (Smith, 1962) comb. nov., P. cyanogaster (Wheeler & Melander, 1901) comb. nov., P. digitata (Smith, 1962) comb. nov., P. distinctipennis (Smith, 1962) comb. nov., P. divisa (Smith, 1962) comb. nov., P. dolichocera (Bezzi, 1905) comb. nov., P. fasciventris (Curran, 1931), P. furcifer (Wheeler & Melander, 1901) comb. nov., P. galactodes (Bezzi, 1909) comb. nov., P. juri (Smith, 1962) comb. nov., P. micrargyra (Bezzi, 1909) comb. nov., P. monstrosa (Bezzi, 1909) comb. nov., P. mundurucu (Smith, 1962) comb. nov., P. mura (Smith, 1962) comb. nov., P. orthoneura (Bezzi, 1905) comb. nov., P. palliata (Coquillett, 1902), P. penicillata (Bezzi, 1909) comb. nov., P. perpulchra (Bezzi, 1909) comb. nov., P. pulchriventris (Bezzi, 1905) comb. nov., P. rotundipennis (Bezzi, 1905) comb. nov., P. seticauda (Smith, 1963) comb. nov., P. variseta (Smith, 1962) comb. nov. and P. wiedemanni (Smith, 1962) comb. nov. A lectotype is designated for P. palliata (Coquillett, 1902).
Empidinae; lectotype; neotropical; new combinations; taxonomy