Agromyza parilis Spencer, 1986

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

Agromyza parilis Spencer

Figs 205-209

Agromyza parilis Spencer in Spencer and Steyskal 1986b: 266.

Description.

Wing length 2.5-2.7 mm (♂), 3.2-3.4 (♀). Length of ultimate section of vein M4 divided by penultimate section: 0.7. Eye height divided by gena height: 2.5-2.8. First flagellomere slightly longer than high and broadly rounded, without apical tuft of pale hairs. Ocellar triangle relatively small and rounded.

Chaetotaxy: Two ori; two ors. Two well-developed dorsocentrals and one smaller anterior seta. Mid tibia with two posteromedial setae.

Colouration: Body dark brown with halter white, and gena and antenna sometimes slightly paler, with first flagellomere orange on inner-basal 1/3 and tarsi slightly paler. Calypter white with hairs dark brown; hairs sometimes yellowish in females.

Genitalia: (Figs 205-209 ) Surstylus narrow and rounded, entirely fused to epandrium and with numerous medial tubercle-like setae. Hypandrium with broadly rounded subtriangular apex; inner lobe with membranous base and inner-distal emargination. Postgonite small and lobate. Halves of basiphallus interlocking at base and with inner margins dark; outer margin weakly sclerotised, wide, wing-like and pointed; distal section distinct with long processes flanking distiphallus. Hypophallus lobate with pointed medial process. Distiphallus of " Agromyza nigripes -type" (capsule-shaped with subbasal opening for entry of ejaculatory duct, pronounced dorsobasal collar, and medial convolution); distiphallus with dark enlarged sclerite above insertion of ejaculatory duct; distal section dark and elongate with medial suture and subapical texturing; transverse dorsobasal band produced ventrally. Ejaculatory apodeme with narrow rounded blade with numerous striations, long stem, and stout base.

Host.

Unknown - likely Poaceae ( Spencer and Steyskal 1986b).

Distribution.

USA: TN, VA*.

Type material.

Holotype: USA. TN: Hamilton Co., East Ridge, 9.v.1952, G.S. Walley, CNC352947 (1♂, CNC).

Material examined.

USA. VA: Fairfax Co., Turkey Run Park , nr. mouth of Turkey Run , 38°57.9'N, 7°09.4'W, Malaise trap, D.R. Smith, 25.v-6.vi.2006 (1♂ 4♀, USNM), 18-30.v.2007 (3♂, USNM), Turkey Run Park, 0.3 km W mouth Turkey Run, 38°58'N, 77°09.6'W, Malaise trap, D.R. Smith, 17-24.v.2006 (4♂ 1♀, USNM), river, 14-17.v.2006 (4♂ 5♀, USNM), Great Falls Park, quarry, 38°59.1'N, 77°14.8'W, Malaise trap, 18-24.v.2007, D.R. Smith (1♂ 3♀, USNM) .

Comments.

While externally similar to a number of small dark eastern Agromyza , the first flagellomere of A. parilis is entirely dark on the outer face and there is no apical tuft of pale hairs in either sex. The male genitalia are most distinctive, however, and should be examined for confident identification.

Figures

Figures 205 - 209. Agromyza parilis Spencer, male genitalia 205 external genitalia, ventral 206 ejaculatory apodeme 207 hypandrium and postgonite, ventral 208 hypandrial complex, left lateral 209 phallus, ventral.