Hemipenthes wilcoxi (Painter)

Ávalos-Hernández, Omar, 2009, A review of the North American species of Hemipenthes Loew, 1869 (Diptera: Bombyliidae), Zootaxa 2074, pp. 1-49 : 43-45

23. Hemipenthes wilcoxi (Painter)

(Figs. 25, 75–76)

Villa wilcoxi Painter, 1933: 15 .

Hemipenthes wilcoxi (Painter) : Hull, 1973: 386

Holotype in USNM.

Diagnosis: Mesonotum anterior margin, mesopleuron, and proepimeron black pilose; sides of first abdominal tergite black pilose (male) or orange yellow pilose (female); abdomen dorsum with black tomentum overall.

Description: Male. Body length: 7–10 mm; wing length: 8–10 mm. Head: Eyes separated by a little more than width of ocellar triangle. Front black pilose, yellowish tomentose, black scales may be present in middle, tomentum not dense. Face brown, rounded, with black hairs and yellowish tomentum, a few black scales in middle and dorsal portion. Scape black, swollen on inner apical margin, with black hairs, twice as long as pedicel; pedicel black, twice as wide as long, with short black hairs in dorsal portion, bare in ventral portion; flagellomere black, longer than scape and pedicel combined; base subconical, tapering to styliform apical two-thirds; stylus minute, terminal. Proboscis short, not projecting beyond oral margin. Palpi black with black hairs. Occiput with short black and white hairs and white scales.

Thorax: Mesonotum anterior and lateral margin black pilose; disc not tomentose, black pilose; bristles black. Mesopleuron black pilose on proepisternum, anepisternum, and katatergite, katepisternum not tomentose, black pilose. Proepimeron with black hairs. Mid coxa with black hairs, all coxae without tomentum. Legs black, femora black pilose and tomentose; bristles black. Halter steam brownish, knob white. Scutellum black, black pilose, not tomentose; bristles black. Black setulae on basicosta. Cells c, sc, br, bm and cell a entirely infuscated (Fig. 25); cell cup entirely infuscated except tip; cells r1 and dm with basal half infuscated; cells r2+3, r5, m2, and cua1 infuscated just at base; cell dm infuscated behind r-m crossvein; r-m crossvein behind middle of cell dm; no crossvein between R4 and R2+3; cell r5 not narrowed at wing margin; first section of vein CuA1 twice the long of r-m crossvein, second section half as long as r-m crossvein, third section twice the long of first two sections combined; cell a as wide as cell cup; alula well developed.

Abdomen: Abdominal dorsum black pilose; black tomentum overall, not dense; sides of abdomen black pilose. Venter black pilose, black tomentose. Genitalia black with black hairs. Epandrium in lateral view, rectangular, lower margin concave in middle, basal corner narrowed; gonocoxite narrow, basal half enlarged; gonostylus small, hooked apically; epiphallus in lateral view narrow ( Fig. 75 ) slightly curved, cap-shaped, apex swollen, rounded; with a ventral extension broad at base with apex acuminate, portion of the epiphallus behind ventral extension longer than aedeagus; epiphallus in ventral view broad ( Fig. 76 ), lateral margins straight, with scattered spines in the middle and dense spines at apex; aedeagus broad at base narrowed at apex, not swollen dorsally; gonopore terminal.

Female. Nearly identical to male. Eyes separated by twice width of ocellar triangle. Mesonotum anterior margin yellow pilose; lateral margin with black and yellow hairs. Tomentum on disc yellowish. Scutellum yellowish tomentose. Sides of first abdominal tergite orange yellow pilose.

Distribution: Mexico (Jalisco, Michoacán), USA (California, Kansas, Nebraska, Utah, Washington).

Specimens examined: USA. Kansas: Pottawatomie Co., 12-V-1963, E. M. Painter (1 male; USNM). Nebraska: 19 mi NE Kimball, 6-VI-1963, R. H. and E. M. Painter (1 male genitalia; USNM). Utah: Utah Co.

Mt. Timpanogos, 4-VIII-1956, D.E. Johnson (1 male 1 female; USNM); Utah Co. Emerald Lake, 23-VII- 1955, D.E. Johnson (1 male; USNM).

Remarks: Although externally Hemipenthes wilcoxi is similar to H. martinorum , it can be distinguished by the absence of scales on the abdomen and by the sinuous color margin on wing. The genitalia are quite different between these species, in H. wilcoxi the epiphallus is cap-shaped with spines and portion of the epiphallus behind ventral extension is longer than the aedeagus, characters not present in H. martinorum . Hemipenthes wilcoxi is the only North American species completely lacking of light colored scales on the abdomen. Just a few specimens have been collected of this species but the collection localities are spread from the center of Mexico to the northwestern USA. Further collecting may show this species to be distributed in Mexico and the whole west of USA, having a distribution similar to that of H. lepidota .

Figures

FIGURES 75 – 76. Hemipenthes wilcoxi male terminalia. 75, lateral view; 76, ventral view.