Syrphini conjunctus Wiedemann, 1830:116

Therantha is a subgenus of Ocyptamus for very large (greater than 12 mm), petiolate, light colored flies in which the three antennal segments are of about equal length. Thus, antenna is elongate. Flies with male genitalia enlarged and vein R4+5 straight.

Hull (1943) described Therantha as a new subgenus of Baccha, but in 1949 he considered it as a different genus. Later, Hull (1949) placed it as a subgenus of Baccha again, but Thompson et al. (1976) moved it under Ocyptamus.

Synonyms:

Baccha atypica Curran, 1930: 16.

Syrphus conjunctus Wiedemann, 1830: 116.

Ocyptamus (Therantha) conjunctus (Wiedemann, 1830).

Wiedemann, C.R.W. (1830) Aussereuropaische zweiflugelige Insekten. Zweiter Theil. Schulz, Hamm. xii + 684 pp., 5 pls. [1830.09.22]

New description:

MALE.

Head: Face with facial tubercle, yellow, yellow pilose except black pilose laterodorsally, white pollinose laterally; entennal base bulbose, enlarged; gena yellow; lunule yellow with inverted W-shaped black macula; frontal triangle yellow except the inverted W-shaped black macula, black pilose; holptic, eye bare; vertical triangle elongate, black, black pilose; antenna brown, scape, pedicel and basoflagellomere subequal; occiput black, white pollinose, withish-yellow pilose, dark pilose dorsally.

Thorax: Scutum black, orangish anteriorly, with lateral broad yellow vitta interrupted after transverse suture, with two submedial broad yellowish-white pollinose vittae and medial yellowish-white pollinose vitta divided medially and broadening posteriorly, with short black pile laterally; postpronotum bare; scutellum yellow with medial brown macula, black pilose, subscutellar fringe absent; subscutellum dark, very large. Pleuron mostly yellow, except posterior anepisternum anteriorly and katepimeron ventrally orangish, and anatergum and basalare black; anterior anepisternum pilose; metaepisternum pilose; metasternum bare; calypter yellow, dorsal calypter with black margin; plumula absent; halter yellow; spiracular fringes yellow. Wing: Wing membrane mostly hyaline, yellow on anterior margin; broadly microtrichose except cell R on posterior half and cell BM on anterior half. Alula broad, microtrichose. Legs: Entirely yellow-orangish, metatarsi slightly darker.

Abdomen: strongly petiolate. Dorsum mainly orange or light brown with yellow fascia on anterior margin of terga 1 to 5; terga 3, 4 and 5 with two submedial narrow yellow vittae, reaching the posterior margin only on terga 4 and 5, very short on tergum 3. Male genitalia very enlarged.

FEMALE.

Very similar to male except frons yellow with the inverted W-shaped black macula between antennal bases and with medial black macula joining black ocellar triangle posteriorly.

Neotropical species known from Brazil and Bolivia.