Dialysis rufithorax (Say 1823)

Dialysis rufithorax Say (PI. I. fig. I, PI. II. fig. 15) 1823. Leptis rufithorax Say. Jour. Acad. Nat. Sci. Phila., Ill, p. 365. 1874. Triptotricha rufithorax Loew, Berl. Ent. Zeits., xxvin, p. 382. 1895. Dialysis rufithorax Williston, Kans. Univ. Quart., in, p. 265.
Brownish yellow mesonotum of male usually somewhat darker, abdomen with a row of elongate medium black spots (sometimes almost wanting in female) which in male are usually larger, better defined, and distinct from a dark basal band which is often present on most of the segments; legs yellowish to brownish, the tarsi, and tip of hind tibiae usually blackened; wings slightly tinged with brownish, a little darker along costal border and toward tip.
Male. — Length, 9 to 10 mm. Head: Frontal triangle and face blackish, light gray pollinose; palpi yellowish often brownish towards tip or almost wholly brownish and with a few pale hairs; proboscis with stalk yellowish, whole apical flattened part blackish above; antennae with third segment and arista blackish, first two segments yellowish brown or often more or less darkened, hairs on cheeks long and pale.
Thorax: Mesonotum and scutellum yellowish, sometimes obscurely darkened in places, shining, with fine short pale hairs, humeri somewhat paler, pleura for the most part bare except for some pale hairs on the metapleura, nearly concolorous with the mesonotum except for the usual silvery white pollinose stripe and a large dark brown polished spot on the mesopleura; metanotum bare, halteres brownish yellow, knob dark brown.
Abdomen: Brownish yellow, segments one to four with a medium dark brown to blackish elongate spot which is often wedge-shaped, however, on the first segment; the remaining segments are sometimes almost wholly blackish except the narrow posterior border, the posterior lateral angles only brownish yellow; sometimes all or part of the first four segments have a darkened basal band which, however, is usually quite distinct from the median spot; pile of dorsum pale, shorter and somewhat ap pressed on disc, longer and more erect on sides.
Legs: Coxae yellowish, with fairly long rather numerous pale hairs; femora a little more brownish than the coxae, the hind pair still darker and distinctly blackened towards tip above; base of fore and middle tibiae brownish yellow, the remainder blackened especially toward tip; the hind tibiae and the tarsi blackish except the hind metatarsi which are brownish yellow.
Wings: Distinctly tinged with brownish, a little more distinctly along costal border, and toward tip, the stigma narrow, dark brown, elongate; veins dark brownish yellow.
Female. — Length, 9 to 12.5 mm. Similar to male except as follows: Front, as usual blackish overlaid with almost white pollen; polished spot on mesopleura concolorous with rest of pleura; abdomen with a small rounded or elongate median blackish spot usually on segments one to four only, sometimes on first two segments, or they may be very faint or almost lacking entirely leaving the abdomen practically immaculate brownish yellow; hairs on thorax and abdomen as usual shorter than on male; wings not quite so strongly tinged with brown although the brownish tinge is quite distinct along the costal border and towards tip; also there is often a distinct brownish tinge at the origin of the radical sector.
Specimens Examined: About 102 males and females.
New Jersey: i 9, Trenton, July 3, 1907; 1 9, July 4, 1910, (Harbeck), [U. S. N. M.]; 1 cT, 2 9, July 4, [A. N. S. P.]. 2 9, Jamesburg, July 2, [Davis]. 1 d Pennsylvania: i 9, Germantown? June 18, 1904, [A. M. N. H.]; 1 d June 24, 1904; 1 9, June 18, 1904, (Harbeck), [U. S. N. M.]; 1 d 1 9, June 18, 26, [A. N. S. P.]. 2 9, Highspire, June 14-20, (W, S. Fisher), [Walton]; 1 9, July 2, 1909, (W. S. Fisher), [Pa. Dept. Agr.]. 3 9, Harrisburg, June 18, (W. S. Fisher); June 26, (W. R. Walton), [Walton]. 1 9 , Heckton Mills, June 16, 191 1, [Pa. Dept. Agr. Coll.]. 3 9, June 21, [Walton]. 1 cf, Progress, [Walton]. 1 9, Montgomery County, June 16, 1895, [U. of Hi.]; 2 d" , June 22, [A. N. S. P.]. 1, Philadelphia, June 15, 1894, [Leonard]. 1 9, Dauphine, June 16, 1917, [Pa. Dept. Agr.]. 1 a", Hummelstown, July 22, 1917, (J. N. Knull), [Pa. Dept. Agr.]. 1 9, Montgomery County, June 16, 1895; 1 9, Castle Rock, Delaware County, June 14, [A. N. S. P.]. I d Glenside, Montgomery County, June 8, 1903. 1 <? , June 15, 1895, [U. of 111.].
Maryland: i 9, Beltsville, June 8, 1916, (W. R. Walton), [Walton]. 1 9, Cabin John Bridge, June 14, 1913, (R. C. Shannon); 1 9, Cabin John, July 12, (R. M. Fouts); 1 9, Plummer's Island, June 18, 1914; 2 9, June 5, 1903, (W. V. Warner, and D. H. Clemons) ; 1 d Marlboro, June 19, 1916, (R. C. Shannon); 1 9. Jackson's Island, June 15, 191 1, (H. S. Barber), [all U. S. N. M.]. 1 9, Camp Meade, May-June, 1919, (R. C. Shannon), [Shannon]. 3 9, June 26, 1912, [Md. Agr. Col.]. 1 9 , Montgomery County, June 20, 1911, (W. T. Davis), [Davis].
District of Columbia: i cf, "D. C," [M. C. Z.; Loew det.]. 1 d Washington, June 8, 1910; 1 9, June 15, 1910, (W. T. Davis), [Davis]; 1 <?, [U. S. N. M.]; 1 9, June 11, 1899, (F. C. Pratt), [U. S. N. M.]; 1 9 , June 10, 1905, (D. H. Clemmons), [U. S. N. M.]. 1 9 , Rock Creek, June 9, 1917, (C. H. T. Townsend), [U. S. N. M.].
Virginia: i o 1 9, Glencarlyn to mouth of 4-mile-Run, June 11, 1916, (W. L. McAtee), [Biol. Surv.]; 1 <?, 2 9 , May 31, (Rohwer), [U. S. N. M.]; 1 d May 30, (N. Banks), [N. Y. S. M.];2 9, June 6, I9i6and2 9 , June 5, 1918, (C.T.Greene),
[U. S. N. M.]; i <?, June 14, (N. Banks), [Banks]; 1 d June 17, (N. Banks), [VV. A. Mann]. 1 9, Dead Run, July 4, 1916, (H. L. Viereck), [Biol. Surv.]; 1 9, June 22, 1915, (R. C. Shannon), [Shannon]. 1 d Falls Church, May 29, (N. Banks), [U. S. N. M.]; 3 9, July 3, 1916, (J. N. Knull), [U. S. N. M.]; 1 9, (C. T. Greene), [U. S. N. M.]; 1 9, June 6, (N. Banks). [N. Y. S. M.]; 1 9, June 19, 1916, (J. N. Knull), [Shannon]; 1 9, May 21, (N. Banks), [Banks]; 1 d June 5, 1916, (C. T. Greene), [U. S. N. M.]; 2 9, June 13, 1913, (Aug. Busck), [U. S. N. M.]. 1 d Chain Bridge, June 14, (S. A. Rohwer), [U. S. N. M.]. 1 9, Buckingham County, June 20, 1919, (W. T. Davis), [Davis]. 2 9, Great Falls, July 5, 1920, (Bridwell), [U. S. N. M.]; 1 9, June 29, 1915; 1 9, June 28, 1917, (C. T. Greene), [U. S. N. M.]; 2 9 , June 12, (N. Banks), [Mann]; 1 d June 16, 1910, (W. T. Davis), [Davis]; 1 o* , June 20, 1916, (C. T. Greene), [U. S. N. M.]. 1 9 , Hyson, June 8, 1913, (Wm. Middleton), [U. S. N. M.].
North Carolina: i d Raleigh, May 26, 1921; 1 9, May 28, 1921, (C. S. Brimley), [N. Car. Dept. Agr.]. 3 <?, 3 9 , "N. Car.," [U. S. N. M.]. 1 9 , Swannanoa, June 22, 1917, (R. W. Leiby), [N. Car. Dept. Agr.].
Georgia: i 9, Clayton, 2000-2700 ft., June, 1909, (C. W. Johnson), [Davis]. 1 9, "Ga." (H. K. Morrison), [U. S. N. M.].
Florida: i 9, "Florida," [U. S. N. M.].
Kentucky: i cr 6 9, "Ky.," (Osten Sacken), [M. C. Z.].
Illinois: 2 9 , Parker, [U. of 111.].
Missouri: 2 9 , Cadet, (J. G. Barlow), [U. S. N. M.].
In addition to the above are two females in the M. C. Z. Coll. without locality label.

Dialysis rufithorax is a species of fly in the family Xylophagidae.