Stipomorpha was established for those Microdon species "with the first two abdominal segments greatly flared and flattened and wider than the thorax; [with] remainder of abdomen immediately compressed into rounded, subcylindrical pipe-like form." This character is of little more than species group significance (Cheng and Thompson 2008).
Ubristes (Stipomorpha) species have postmetacoxal bridge complete; abdomen triangular, broad basally, strongly narrowed apically, long, not equilateral; metatibia with long pile along dorsal edge, forming a distinct brush of pile; basoflagellomere not furcate, usually not greatly elongate; metabasitarsomere not enlarged; and vein R4+5 with an appendix extending posteriorly into cell R4+5.
Adapted from original description (Shannon 1927).
MALE.
Very similar to goettei in coloration and to trigoniformis in structure. Antennal segments 1:0.25:1; face and front broader than in trigoniformis; pro- and mesolegs yellow, tarsi dark brown; metafemur yellowish, tibia and first three tarsal segments dark brown, dorsal incision on tibia not as pronounced as in trigoniformis; abdomen as in trigoniformis; wings subhyaline, no whitish vitta.
Ubristes (Stipomorpha) fraudator (Shannon, 1927).
Shannon, R.C. (1927) A review of the South American two-winged flies of the family Syrphidae. Proceedings of the United States National Museum 70(9)[= No. 2658], 34 p. [1927.04.29]
Length: body, 8.5 mm; wing, 6 mm (Shannon 1927).
Neotropical species, which type locality is "Amazon".
unless otherwise stated