Ophiomyia laticolis, Lonsdale, 2021

Lonsdale, Owen, 2021, Manual of North American Agromyzidae (Diptera, Schizophora), with revision of the fauna of the " Delmarva " states, ZooKeys 1051, pp. 1-481 : 1

Ophiomyia laticolis sp. nov.

Figs 367-371

Description.

Wing length 2.2-2.3 mm (♂). Female unknown. Length of ultimate section of vein M4 divided by penultimate section: 0.7-0.8. Eye height divided by gena height: 9.0 (non type). Eye angled diagonally. Facial carina thin along length with narrow medial bulb. Gena shallowly produced, forming a 45° angle. Clypeus produced and abruptly narrowed apically with apex truncated. Buccal cavity narrowed anteriorly with anterior margin nearly straight. Distance between crossveins more than length of dm-m. Ocellar triangle and fronto-orbital plate (narrow) subshiny. Head damaged.

Chaetotaxy: Male with vibrissal fasciculus ~ 1/2 length of gena. Two ori (slightly thinner); two ors. Mid tibia with one weak posteromedial seta.

Colouration: Gena relatively high, flat and pale in holotype. Body, including halter dark brown with frons darker. Wing veins brown. Calypter margin and hairs brown.

Genitalia: (Figs 367-371 ) Epandrium broad, rounded, narrower in lateral view and slightly shorter to dorsum. Surstylus fused to epandrium, 1/2 length of distal region of epandrium; apex narrower, rounded; inner surface with two scattered rows of tubercle-like setae. Metepiphallus small and pale with one pair of ventromedial spines. Halves of basiphallus broadly fused at base; left sclerite short, weakly sclerotised and ill-defined, and right sclerite longer, truncated and with slight dextral curve. Distiphallus strongly spinulose on inner surface but with few other internal elaborations; slightly flattened and subquadrate in ventral view.

Host.

Unknown.

Distribution.

USA: MD, VA.

Etymology.

The specific name compounds the Latin for wide (latus) and penis (colis).

Type material.

Holotype: USA. MD: Montgomery Co., Bethseda, 28.iv.1968, G. Steyskal (1♂, USNM),.

Paratype: USA. VA: Fairfax Co., Turkey Run Park, 0.3 km W mouth Turkey Run, 38°58'N, 77°09.6'W, Malaise trap, river trap, 17-24.v.2006, D.R. Smith (1♂, USNM).

Comments.

The new species Ophiomyia laticolis is highly similar to O. ambrosia Spencer from California ( Spencer and Steyskal 1986b: figs 232-234), but the genitalia appear to be slightly smaller, the base of the mesophallus is nearly level with the base of the distiphallus, and the sides are severely flared, almost forming one pair of lateral points. Externally, the gena of O. ambrosia is slightly flatter and paler, but this may be an artifact of preservation; the eye is 5.6 × higher than the gena, and wing length is similar (2.2 mm).

The genitalia of this species also closely resemble those of Ophiomyia duodecima Spencer (Quebec; Spencer, 1969: figs 134-136), in that the distiphallus is subquadrate in ventral view. The distiphallus of this Canadian species, however, is 2 × as large, the mesophallus is small and gracile, the left sclerite of the basiphallus is larger and not basally fused to the right sclerite (a possible artifact of illustration) and the gena is much higher (1/4 eye height).

Figures

Figures 367 - 371. Ophiomyia laticolis sp. nov., male genitalia 367 hypandrium, ventral 368 hypandrial complex, left lateral 369 phallus, ventral 370 external genitalia, left lateral 371 external genitalia, posterior.