Orphnabaccha coerulea (Williston, 1891):38

The subgenus Orphnabaccha is distinguished by having the metasternum pilose, anterior anepisternum pilose, facial tubercle well-developed and metaespisternum bare.

Vockeroth (1969) divided Orphnabaccha in three species groups based on abdomen shape and male genitalia. The coreuleus group have black and grey abdomen, black face, darkened costal area and infuscate apical wing. The amplus group has a typical Syrphus-type abdominal pattern and furcate superior lobe of the male genitalia. The caldus group is more variable but members share yellow face with medial black vitta and abdominal yellow markings.

Ocyptamus (Orphnabaccha) coeruleus (Williston, 1891).

Williston, S.W. (1891-92) Fam. Syrphidae. Biologia Centrali Americana, Zoologia - Insecta - Diptera. 3: 1-56; 57-72; 73-78, pl. 1, 2, figs. 1-12.

New description:

MALE.

Head: Face with facial tubercle, black, with two medial yellow maculae on lateral margins, white pollinose laterally, black pilose; gena black, white pilose, white pollinose; lunule rugose, shiny black with ventral margin yellow; frontal triangle black, bluish-white pollinose, black pilose; holoptic, eye bare; vertical triangle black, black pilose; antenna dark brown, basoflagellomere orange ventrally; occiput black, silver pollinose, withish pilose on ventral 2/3, black pilose on dorsal 1/3.

Thorax: Scutum bluish-black, densely bronze pollinose with two dorsomedial dark pollinose vittae separating posteriorly, with long yellow pile; postpronotum dark, bare; notopleuron mostly black pilose; scutellum bluish-black, mostly black pilose with yellow pile, subscutellar fringe sparse with long dark pile. Pleuron bluish-black, white pollinose, pale pilose with some black pile on posterior anepisternum; anterior anepisternum pilose; metasternum pilose; calypter white; plumula white; halter dark; spiracular fringes white. Wing: Wing membrane brownish, anterior margin very dark brown, with small vitta on Rs furcation, also dark before vein h; extensively microtrichose, bare on basal cell R. Alula broad, bare with microtrichia apically. Legs: coxae, trochanters and femora black, femora yellow apically, pro- and mesotibiae yellow, pro- and mesotarsi yellow, except the apical 3 tarsomeres dark; metatibia dark, yellow on apical 1/4; metabasitarsomere yellow, the others tarsomeres dark.

Abdomen: Parallel-sided, unmargined. Dorsum mainly shiny bluish-black, white pilose; terga 2, 3, 4 and 5 with medial semicircular opaque black macula, which on tergum 2 does not reach anterior margin, Sterna very shiny black.

FEMALE.

Very similar to male except: frons black, shiny blue, white pollinose laterally, with medial bronze pollinose vitta, ocelalr triangle shiny black; wing more bare mediobasally, cells BM and R extensively bare; terga 3 and 4 with opaque black macula divided narrowly medially.

Described originally as Baccha, Hull (1949) designated this species as the type species of his new genus, Orphnabaccha. Thompson et al. (1976) included it in Ocyptamus.

Synonym:

Baccha coeruleus Williston, 1891: 38.

GenBank accession number for this species are: protein-coding gene COI (EU409138), rRNA 28S (EU409193) and 18S (EU409254).

Species known from Texas, south to Costa Rica.