Pelignellus subnudus Sturtevant & Wheeler, 1954

Zatwarnicki, Tadeusz & Mathis, Wayne N., 2019, New discoveries in New World Atissini as revealed in revision of Pelignellus Sturtevant & Wheeler (Diptera: Ephydridae), Israel Journal of Entomology (Oxford, England) 49 (2), pp. 11-26 : 22-24

Pelignellus subnudus Sturtevant & Wheeler, 1954

( Figs 1, 11–16)

Pelignellus subnudus : Sturtevant & Wheeler 1954: 252 [ United States, California, Orange, Corona del Mar; HT ♂, ANSP (6700)]; Wirth & Stone 1956: 464 [key], 467 [list]; Wirth 1965: 737 [Nearctic catalog]; Wirth et al. 1987: 1024, fig. 21 [head].

Atissa subnuda : Mathis & Zatwarnicki 1990 b: 896 [generic combination]; 1995: 56–57 [world catalog].

Diagnosis: Small shore flies, body length 1.05–1.55 mm. Body mostly gray with central portion of scutum brown.

Head ( Figs 1, 11, 12): Frons multicolored, posterior portion at level of ocellar triangle brownish gray to blackish gray, parafrons gray, becoming lighter, whitish gray anteriorly, mesofrons forming irregular triangle, wide, posterior portion robust, becoming abruptly narrowed just anterior to anterior ocellus, coloration of narrowed portion purplish blue posteriorly, gradually becoming reddish orange at vertex; 1 pair of interfrontal setae anterior of anterior ocellus; 3 short fronto-orbital setulae in parafrons, anterior 2 proclinate, aligned, posterior setula larger than anterior 2, lateroclinate to lateroreclinate, inserted medially from alignment of anterior 2. Antenna mostly yellowish orange to orange, dorsum sparsely invested with whitish gray microtomentum; basal half of arista swollen, bearing 3–4 dorsal rays, these relatively short, none greater in length than height of basal flagellomere, apical half of arista style-like. Face in lateral view concave, with silvery microtomentum, epistomal margin robustly produced. Facial and genal setae and setulae gray to silvery while. Eye elliptical, obliquely oriented. Gena-to-eye ratio 0.81–0.82.

Thorax: Scutum with much of midportion brown, anterior, lateral, and usually posterior margins gray; scutellar disc variable from mostly gray to mostly brown; 1 pair of presutural acrostichal setae and only posterior dorsocentral seta better developed; other acrostichal and dorsocentral setulae short. Pleural area generally gray, pleural setae reduced, pale colored. Wing uniformly faintly tan, partially hyaline; wing ratio 0.45–0.49; costal vein ratio 0.75–1.00; M vein ratio 0.52–0.56. Legs generally gray to blackish gray, posterior surfaces darker and subshiny; only basal 3 tarsomeres yellowish.

Abdomen: Tergites uniformly gray, similar to pleural areas. Male terminalia ( Figs 13–16): Epandrium in posterior view ( Fig. 13) as an inverted diamond-shaped U, wider than high, in lateral view ( Fig. 14) almost parallel sided, narrowed on ventral ¼; cercus in posterior view ( Fig. 13) broadly ovate on dorsal ⅔, ventral ⅓ narrowed, in lateral view ( Fig. 14) narrowly semihemispherical; surstylus in posterior view ( Fig. 15) relatively short, wide, thumb-like, length less than half length of cerci, bearing several evenly scattered setulae, in lateral view ( Fig. 16) wide basally, tapered gradually to relatively broadly rounded apex; postgonite in lateral view ( Fig. 16) elongate, irregularly funnel shaped, broad on basal ⅓, thereafter gradually tapered apical half almost parallel sided; in ventral view ( Fig. 15) elongate, narrow, irregularly triangular, medial surface shallowly angulate, lateral surface shallowly concave, apex slightly expanded; pregonite in lateral view ( Fig. 16) tiny, more or less triangular, bearing 2 small, apical setulae, in ventral view ( Fig. 15) oriented obliquely medially; fused aedeagus/phallapodeme in lateral view ( Fig. 16) elongate, apical half digitiform, rod-like, basal half more robust and with shallow concavity sub-basally, in ventral view ( Fig. 15) moderately narrow, moderately elongate, apical ¾ thumb-like, almost parallel sided, apex truncate; hypandrium in lateral view ( Fig. 16) very slender, elongate, almost straight to very shallowly concave.

Type material examined: holotype ♂ labeled “ Corona del Mar [,] (33°35.9'N 117°52.4'W) Cal. M[a] r[ch] 19 [handwritten; yellow white]/ TYPE 6700 [number handwritten; red]/ HOLOTYPE Pelignellus subnudus St [urte]v[an]t & Wh[ee]l[e]r [red].” The holotype is glued to a large paper triangle, is in very good condition, and is deposited in the ANSP (6700). Twenty­six paratypes (4♂ 22♀; ANSP, USNM) bear the same locality data as the holotype with dates of collection from 3–19.iii.1950 .

Type locality: United States, California, Orange, Corona del Mar .

Distribution: Nearctic: United States (California).

Remarks: Thus far, this species is only known from the type locality, which is along the maritime coast in southern California. We suspect that this species is more widespread than is indicated by current collection records.