Anu una Thompson, 2008:9

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).

In appearance and behavior Anu una is related to Sphaerophoria.

Adapted from original description (Thompson 2008).

MALE.

Head: Face yellow, except tubercle brown, white pilose; gena yellow, white pilose; frontal triangle yellow, black pilose; vertical triangle shiny, black, black pilose; occiput black, white pollinose and pilose on ventral 2/3, black pollinose dorsally except along eye margin, black pilose dorsally; antenna orange except basoflagellomere brownish orange on apical 3/4, black pilose; arista brown.

Thorax: Postpronotum yellow; scutum shiny, black except with yellow lateral vitta from postpronotum to transverse suture, black pilose; scutellum yellow except black basolateral side, black pilose; pleuron shiny, extensively black, yellow dorsad of procoxa, yellow dorsally on katepisternum, yellow posteriorly on anepisternum, yellow narrowly and dorsally on anepimeron, and yellow on katatergum; calypter, plumula and halter yellow. Wing: Hyaline, microtrichose except bare basal 7/8 of cell C, basal 1/8 of cell BM and CuP. Legs: Coxae and trochanters yellow, pale pilose; femora brownish yellow, black pilose; tibiae brownish yellow on basal 3/4. brown apically, black pilose; tarsi black, black pilose.

Abdomen: Terga brownish yellow on lateral 1/4, blackish brown medially, long white pilose on 1st and 2nd terga, short, sparse black pilose elsewhere; sterna brownish yellow.

FEMALE.

Similar to male; front yellow on ventral 1/4, black dorsally, black pilose; 1st tergum black, shiny, white pilose; 2nd tergum shiny, black except yellow small macula on lateral 1/4 medially, white pilose except black pilose medially; 3rd & 4th terga shiny, black except larger yellow triangular macula on lateral 1/3 medially and yellow apical margins; 5th tergum black, black pilose.

Variation. The above description is of the holotype male and allotype female and will match most specimens precisely. However, a few individuals tend to be darker, with the darkest individuals having broad black facial vitta and an almost entirely dark pleuron.

Anu una Thompson, 2008.

Thompson, F.C. (2008) A conspectus of New Zealand flower flies (Diptera: Syrphidae) with the description of a new genus and species. Zootaxa 1716, 1-20. [2008.02.29]

Anu una looks like and acts like a small Sphaerophoria species.

Body length: 5-6 mm.

Anu, along with Exallandra, Giluwea and Sphaerophoria (including Loveridgeana) probably form a monophyletic group characterized by yellow mesonotal vitta, loss or reduced subscutellar fringe, loss or reduced lingula, bare or reduced metasternal pile, and Anu is probably the sister to Giluwea as their genitalia are most similar (both have asymmetric surstyli) (Thompson 2008).

Species endemic from New Zealand, found in North Island and South Island.

There is a paratype collected in a Nothofagus forest.