Leucophora subvittata (Malloch, 1934)

Figs. 41–42

Hammomyia subvittata Malloch, 1934:192 . Fig. 27g (female cerci), Type-locality: Argentina, Bariloche. Albuquerque, 1953: 538 (catalogue).

Leucophora subvittata Pont, 1974:7 (catalogue); Ramírez-Mora et al. 2023:323 (catalogue).

Diagnosis. Leucophora subvittata can be differentiated from its congeners by the following combination of characters: arista short plumose with longest hairs about 2x the basal diameter of arista, genae more than 0.5x the eye height, three longitudinal dorsal vittae on thorax, central vitta not extending over the scutellum; wing without darkened transverse veins.

Material examined. Holotype 1 ♂ (USNM): Bariloche, Rio Negro, Agr [Argentina] Nov 1926, R & EShannon. Hammomyia subvittata Type det. JRMALLOCH

Paratypes 1 ♂ (USNM). Bariloche, Rio Negro, Agr [Argentina] Nov 1926. R & EShannon Hammomyia subvittata Type det. JRMALLOCH . 1 ♀ (BMNH). Peulla, Chile https://data.nhm.ac.uk/object/92458a56-8cf2- 4d5e-af47-4333b93fcab3

Description

Male (Fig. 41)

Body length, 8.5 mm, wing length 7.0 mm

Coloration (Fig. 41). Head black with white silvery pruinosity; frontal vitta black with some grey pruinosity (Fig. 41B). Parafacialia in profile with a wide shifting black patch from level of insertion of antennae to level of postpedicel tip (Fig. 41C), genae with a black patch from the vibrissal angle extending to behind the eye, connected with the parafacialia patch on anterior margin. Antennae black, scapus dark brown on distal margin, arista lighter at middle. Prementum and palpi dark brown to black. Thorax black with grey pruinosity; with three longitudinal dark brown vittae (Fig. 41D), central vitta filling the space between the acrostichal setae, not extending over the scutellum, a pair of lateral vittae filling the space from the posthumeral and supra-alar presutural setae and intralar and supra-alar postsutural setae. Disc of scutellum without brown marks. Base of dc setae brown. Anepisternum with a brown patch below notopleuron (Fig. 41A). Legs dark brown to black. Apex of femora brown, mid and hind tibiae brownish. Tarsomeres dark brown. Wing membrane hyaline with brown to dark brown veins. Haltere brown. Abdomen black with grey pruinosity, with a longitudinal dark brown vitta.

Head. Fronto-orbital plate at narrowest point 0.8x width of anterior ocellus, widening anteriorly, with scattered short setulae; frontal vitta at narrowest point 1.9x width of anterior ocellus, slightly widening towards lunule; eyes separated at narrowest point 3.5x width of anterior ocellus (Fig. 41B). 7–8 pairs of fr s, with short setulae in between (Fig. 41C). infr s shorter than the longest fr s. oc s strong and longer than infr s; ocellar triangle with 2 additional pairs of setulae; poc s shorter than oc s. i vt s the longest setae on head, convergent; o vt s pair thin and shorter than poc s, slightly proclinate. Postpedicel 1.8x the pedicel length; arista 1.8x the postpedicel length, pubescent, longest hairs almost 2x the basal diameter of arista. Parafacials 0.5x width of eye. Genae below lowest point of eye margin 0.3x eye height. Vibrissal angle in profile reaching the level of frontal angle (Fig. 41C).

Thorax. Chaetotaxy: 5 pairs of psut acr s, prescutelar pair longer than the longest presut acr s (Fig. 41D). Prealar seta absent. 6 anepst s. 1+2 kepst s.

Female (Fig. 42)

Body length, 7.2 mm, wing length 6.1 mm

Differs from male as follows:

Coloration (Fig. 42). Head black with light yellowish pruinosity; frontal vitta black with some grey pruinosity, parallel sided (Fig. 42B). Parafacialia in profile with a wide shifting dark brown patch from level of insertion of antennae to level of postpedicel tip (Fig. 42C), genae with a dark brown patch from the vibrissal angle extending to behind the eye. Antennae dark brown to black, pedicel lighter distally, arista lighter at middle. Prementum and palpi dark brown to black. Thorax. Vittae less defined than in male (Fig. 42A, D). Anepisternum with a brown patch below notopleuron (Fig. 42A). Legs with hind tibiae brown. Abdomen. Black with brownish-grey pruinosity, with a diffuse longitudinal dark brown vitta.

Head. Fronto-orbital plate at narrowest point 1.4x width of anterior ocellus, widening anteriorly, with scattered short setulae; frontal vitta at narrowest point almost 5.0x width of anterior ocellus, slightly widening towards lunule; eyes separated at narrowest point 9.0x width of anterior ocellus (Fig. 42B). 7–8 pairs of fr s, with short setulae in between (Fig. 42C). infr s shorter than the longest fr s. oc s strong and longer than the longest fr s; ocellar triangle with 3 additional pairs of setulae; poc s shorter than oc s. i vt s strong and the longest setae on head, convergent; o vt s thinner and shorter than poc s, slightly divergent. Postpedicel 2.0 x the pedicel length; arista 2.1x the postpedicel length, pubescent, longest hairs about 3 x the basal diameter of arista. Parafacials 0.4x width of eye. Genae below lowest point of eye margin 0.6x eye height. Vibrissal angle in profile reaching the level of frontal angle (Fig. 42C).

Remarks. The description provided for this species is based exclusively on type material photographs. In external appearance, L. subvittata looks similar to L. chilensis, but differs in having the central longitudinal dorsal vitta on the thorax not extending over the scutellum, and the lateral brown marks on abdominal tergites 3–5 of the male L. subvittata are absent. The females resemble those in L. delestero sp. nov., and L. plumiseta; however, L. subvittata can be separated from L. delestero sp. nov., by the wider interfrontal plate and parafacialia and a higher genae; from L. plumiseta differs in having shorter hairs on the arista, about 2x the basal diameter of arista, and wider parafacialia.

Distribution. Neotropical: ARGENTINA (Bariloche), CHILE (Peulla) (Fig. 57B).