Ocyptamus (Hybobathus) amabilis (Hull)
Ocyptamus (Hybobathus) amabilis (Hull, 1943).
Hull, F. M. 1943. New species of syrphid flies in the National Museum. Journal of the Washington Academy of Sciences 33(2), 39-43.
Ocyptamus (Hybobathus) amabilis (Hull, 1943).
Hull, F. M. 1943. New species of syrphid flies in the National Museum. Journal of the Washington Academy of Sciences 33(2), 39-43.
Synonym:
Baccha amabilis Hull, 1943: 74.
Hybobathus was a genus described by Enderlein (1938) for his species quadrilineatus. Thompson (pers. com.) consideres quadrilineatus as a member of the lineatus group sensu Hull (1949). Hybobathus species are distinguished by linear, vittate pattern upon the petiolate abdomen. They are light yellow flies with scutum yellow laterally, yellowish-green pollinose medially, with wing light greenish yellow and legs yellow.
O. amabilis is somewhat similar to Ocyptamus flavipennis Wiedemann, with narrower abdomen and fewer linear vittae. Hull (1943) placed this species in the lineatus group.
O. amabilis has second abdominal tergum slightly constricted in the middle, about twice as long as its greatest width or longer; sides of second tergum yellow on basal two-thirds. Third and fourth terga with sublateral vittae incomplete, though reaching through most of the tergum and curved or attenuate (Hull 1943).
Adults are pollinators and feed on pollen and nectar.
Adapted from original description (Hull 1943).
MALE
Head: Vertex shining black. The front on dorsal third is opaque black viewed vertically, and at the eye margin at each lower angle of this triangle there is a small, punctate, white, hemispherical pollinose macula. The very swollen front is shining brown below, yellowish above the antennae. Face tuberculate, metallic black, with another white pollinose macula on each side at the upper eye margin. Antennae small, light brown, the basoflagellomere orange below; pedicel nearly as long as basoflagellomere.
Thorax: very dark brown, with a pair of linear, widely separated, very obscure, gray or blue-black vittae; medially there is a pair of close, still more faint, brown-black vittae. Scutellum light brown, translucent, its pile and that of scutum erect, black, its basal fringe of five or six pale pile. Legs: All the femora light yellow, except a wide subapical ring upon the metafemur; remainder of first two pairs yellowish except the tarsi; tarsi and remainder of metalegs blackish brown; all pile blackish; mesofemur with a long fringe on the posterior surface. Wings: light gray, very gradually becoming smoky brown on the basal third.
Abdomen: moderately slender, parallel-sided from beyond the second tergum, which is constricted a little upon the basal half; color of abdomen light orange-brown, with darker vittae. Terga 3-5 with a pair of very narrowly separated (confluent upon the fifth tergum) and narrow, medial vittae; these terga, on each side, with a pair of narrow lateral vittae, each pair of which is confluent upon its posterior half, and whose outer section comprises the lateral margin itself. Second tergum light brown with a small, rounded, yellowish, diffuse spot near the middle upon each side. Abdominal pile black, fairly long and abundant on the sides of the first segment.
Body length: 7 mm (Hull 1943).
In the molecular analysis by Mengual et al. (2008), Ocyptamus (Hybobathus) lineatus was resolved as sister group of O. (Hermesomyia) wulpianus, as a sister group of a clade comprising other Ocyptamus species and the genus Toxomerus.
Type locality: Peru, Iquitos.