Phaonia subdecussata Hennig, 1963

Sorokina, Vera S. & Pont, Adrian C., 2011, Fanniidae and Muscidae (Insecta, Diptera) associated with burrows of the Altai Mountains Marmot (Marmota baibacina baibacina Kastschenko, 1899) in Siberia, with the description of new species, Zootaxa 3118, pp. 31-44 : 42

Phaonia subdecussata Hennig, 1963

Material examined. 2 males, RUSSIA, Respublika Altai, Kosh-Agachskiy rayon, verkhov’ya r. Naryn-Gol [upper River Naryn-Gol], 2520 m, 49º49'N 89º32'E, na surchinakh [from Marmot burrows], 15–19.vii.2009, V. Sorokina ( SZNM & BMNH); 4 males and 1 female, Respublika Altai, Kosh-Agachskiy rayon, dolina r. Tara [River Tara valley], 2300 m, 49º39'N 88º13'E, na surchinakh [from Marmot burrows], 11.vii.2009, V. Sorokina, T. Novgorodova (2 males OUMNH & BMNH, rest SZNM).

Comments. This species belongs to the Phaonia tenuiseta group, which is defined by the presence of setulae on the prosternum. Males can be recognised by the absence of presutural acrostichal setae, the absence of a p seta on fore tibia and an ad seta on mid tibia, by the presence of only 3–4 short weak pv setae on hind femur, and especially by the presence of a tuft of short spinose setulae on the ventral surface of hind trochanter. As in other species of the group, the tarsi, especially fore tarsi, are yellowish-red on the ventral surface, and the eyes are reduced in size, resulting in broad frons, parafacial and gena. The female has 2 p setae on fore tibia and 2 ad on mid tibia. Tergites 1+2–3 bluishgrey pruinose, tergites 4–5 shining silvery with a shifting abdominal pattern.