Anu una Thompson  

Anu is distinguished from all other Syrphidae by the male terga reduced apicomedially so that the abdomen may be bent into an apicodorsal curve (almost always in dead specimens); the 1st tergum is divided into lateral plates as the medial area is entirely membranous; and the scutellum is concave apicomedially with the subscutellum greatly produced so as to be visible dorsally. In the last key to the genera of Syrphini (Vockeroth 1969), Anu runs to couplet #24. The statement about the scutellum in couplet #21 should be ignored; otherwise Anu agrees well with the rest of the first alternative. Anu is distinguished from both Exallandra and Sphaerophoria by the unique autapomorphic characters listed above (Thompson 2008).