Phyladelphus, Becker, 1910

Deeming, John C., 2018, A revision of the Afrotropical species of Pachylophus Loew (Diptera: Chloropidae) and some related Ovoviviparous genera, Zootaxa 4482 (1), pp. 1-51 : 25

Key to Western Old World species of Phyladelphus

1 Lateral edge of abdomen yellowish, contrasting with the black dorsal surface and the ventrally-facing lateral extremities of the tergites. Ocellar prominence lightly dusted, the dust extending onto a slightly depressed oval area on either side of it. A pair of submedian yellow vittae present on entire length of scutum. Parafacial and gena deeper, two thirds as deep to deeper than the postpedicel........................................................................................... 2

- Abdomen black throughout. Ocellar prominence bare or dusted, lacking any tongue of dust extending laterally from it. Yellow markings on scutum restricted to notopleuron and hind margin of postpronotal lobe. Gena narrower, in depth not exceeding one half of depth of postpedicel. Arista lanceolate with short fine pilosity......................................... 3

2 Gena deeper than postpedicel. Median black vitta of scutum extending to tip of scutellum. Inner vertical seta slightly longer than the outer. Dusted area on either side of ocellar prominence yellowish in ground colour. Arista acute apically, on apical quarter of its length the lanceolate core filiform with compact rays................................................................................................... thalhammeri Becker ( Hungary, Mediterranean and Black Sea)

- Gena two thirds as deep as postpedicel. Disc of scutellum yellow throughout. Outer vertical seta slightly longer than inner. Ocellar triangle black throughout. Arista lanceolate throughout and rounded apically, the flattened blade-like core with very short setae.......................................................... geminus Becker (highlands of East Africa)

3 Ocellar prominence dusted. Gena narrower, less deep than arista. Apical segment of arista apically rounded and longer than the combined length of the pedicel and postpedicel.......................................... woodi sp. n. (S.E. Africa)

- Frontal triangle completely undusted. Gena slightly wider, wider than the arista. Apical segment of arista pointed apically and not longer than the combined length of pedicel and postpedicel.............................. maraisi sp. n. (Namibia)