Shore Fly

Mosillus tibialis Cresson

Mosillus tibialis Cresson, 1916:149.—Wirth, 1965:734 [Nearctic catalog]; 1968:3 [Neotropical catalog]; 1969:150–151 [review].—Cole, 1969:396 [list, California].—Tenorio, 1980:270 [review, Hawaii].—Mathis, 1989:640 [Australasian/Oceanian catalog].

Gymnopa tibialis.Cresson, 1922:329 [generic combination]; 1942:106 [review, Nearctic]; 1946a:136 [review, Neotropical].—Cole, 1923:478 [list, Gulf of California].—Wirth and Stone, 1956:466 [key, California].

DESCRIPTION.—Small to medium-sized shore flies, length 1.90 to 3.75 mm.

Head (Figures 38–43): Frons wider than long, frons width-to-length ratio averaging 0.85; mesofrons narrowly U-shaped, microtomentum very sparse, coarsely microsculptured, appearing mostly granulose, bearing numerous setulae; parafrons mostly smooth, appearing satiny. Antenna, including arista, black; flagellomere 1 with moderately dense vestiture of grayish black pubescence. Face, including antennal grooves, extensively microtomentose, obscuring most microsculpturing beneath, microtomentum as 2 broad, vertical stripes on either side of midfacial prominence, lateralmost sometimes connected with microtomentum in antennal groove; anteriormost facial projection bluntly tear-drop shaped, bulbous ventral portion wide; clypeus mostly bare of microtomentum, very finely microsculptured, appearing mostly smooth. Parafacial wide, conspicuously wider at narrowest point than width of anterior ocellus; parafacial at level of antenna with 1 large, vertically elongate microtomentose area, obtusely pointed ventrally, length subequal to combined length of antennal segments. Gena with 1 or 2 wrinkles anteriorly, otherwise completely bare of microtomentum, smooth, shiny; gena high, eye-to-cheek ratio averaging 0.59.

Thorax (Figures 44–49): Mesonotum extensively and densely microtomentose, microtomentum mostly brownish gold (more so laterally) to mostly whitish gray, sometimes in a pattern with darker color as a medial stripe or with posterior with microtomentum sparser; short, linear, transverse bare areas extended from dorsal angle of notopleuron; scutellum broadly trapezoidal, with posterior angles rounded and posterior margin very shallowly convex; scutellum bearing 4–5 setae on each side that arise from basal tubercles; anepisternum with small patch of microtomentum at posterodorsal corner, otherwise very sparsely microtomentose. Spine-like setae of fore femur small; fore tibia reddish yellow; middle tibia yellowish orange; fore basitarsomere yellow, others dark, mostly blackish brown; hind basitarsomere yellow. Costal vein ratio averaging 0.41; vein M ratio averaging 0.60.

Abdomen: Generally shiny, smooth, setulae sparse; 2nd abdominal tergum with median depression narrow, linear posteriorly; 5th tergum with dorsomedial area very densely microtomentose and bearing numerous setulae. Male terminalia (Figures 50–55): epandrium comparatively long, extended along anterior margin to well below cerci externally to merge with basal margin of surstylus; surstylus appearing comparatively short externally, distinctly less than length of cerci, ventral dististylar margin truncate, ventromedial surface bearing longer setulae; lateroventral projection of surstylus rounded; postgonite narrowed medially in lateral view, apical lobe bearing seta slightly flared laterally in dorsal view; dorsal lobe smaller than setal bearing lobe; aedeagus short, length subequal to that of aedeagal apodeme, trapaezoidal in dorsal view; aedeagal apodeme with ventral flange abruptly produced; hypandrium bare, elongate, with deep pocket anteriorly.

TYPE MATERIAL.—The holotype male of Mosillus tibialis is labeled “[USA. Cape May County] Wildwood NJ VII, 18, 1908 [18 Jul 1908]//Holo-TYPEMosillus tibialis E.T. Cresson Jr. [species name and gender symbol handwritten, dark red]/ANSP [yellow].” The holotype is double mounted (minuten in a rectangular piece of cardboard), is in good condition, and is deposited in the ANSP (6103).

OTHER SPECIMENS EXAMINED.—CANADA. British Columbia: Vancouver Island, Cowichan Bay, 12 Jul 1924, A.L. Melander (2, 3; ANSP, USNM). Nelson, 17 Jul 1910 (1; USNM).

ECUADOR. Manabi: Bahia, 10 Jan 1978, W.N. Mathis (1, 2; USNM).

GUATEMALA. Coban, Alta Vera Paz, 14 May 1926, J.M. Aldrich (1; USNM).

MEXICO. Baha California Norte: Estero Beach (9 km S Ensenada), 5 Jul 1973, P.H. Arnaud, Jr. (1; CAS). Turnoff highway 1 to Motel Durado (3 km S Ensenada), 18 Jul 1977, D. Weissman, C. Mullinex (4; CAS). Baja California Sur: Aqua Caliente (San Carlos; 18.5 km east of Maneadero), 6 Jul 1973, P.H. Arnaud, Jr. (6; CAS). Mulegé, 14 May 1921, E.P. Van Duzee (3, 3; CAS, USNM). Sierra de la Giganta (22 km W Loreto, Rancho Vinateria), 9 Aug 1975, W.E. and W. Savary, C.L. Mullinex (2; CAS). Chiapas: Finca Prusia (33 km S Jaltenango, 1000 m), 10–12 May 1985, W.N. Mathis (20, 31; USNM); San Cristobal de las Casas, 13 Aug 1959, N.L.H. Krauss (1; USNM). Chihuahua: Chihuahua, 12 Aug 1951, P.D. Hurd (1; USNM). Districto Federal: Milpa Alta, 8 Jul 1953, R. Nettel F. (1, 2; USNM). Jalisco: Guadalajara, 27 Jun 1969, S.C. Williams (1; CAS). México: Texcoco, 28 Feb 1957, W.W. Gibson (2; USNM); Texcoco, El Batan, 4 Jan 1957, J.L. Carrillo (1; USNM). Oaxaca: L.O. Howard (1; USNM). Sonora: Rocky Point (marsh), 21 Apr 1947, A.L. Melander (1, 5; USNM). Veracruz: Xico, 7 Sep 1951, A.H. Sturtevant (1, 1; USNM).

PERU. Lima: Lima (Lagunas de Villa), 14 Feb–30 Aug 1984, 1988, W.N. Mathis (15, 13; USNM).

UNITED STATES. Alabama: Mobile Co., Kushla, 11 Jun–24 Oct, 1914, 1916, 1924, A.H. Sturtevant (11, 5; USNM). Arizona: Apache Co., Adamana, 12 Jun 1950 (1; UTA). Coconino Co., Bill Williams Forest, Aug, F.H. Snow (7, 9; 2ex; ANSP); Supai, Havasu Canyon (3500 ft, = 1067 m), 2 Aug 1934, F.E. Lutz (2; AMNH); The Gap, 17 Jun 1950, A.H. Sturtevant (2, 1; USNM); Todds Lodge (Oak Creek Canyon), 9 May 1950, J. Sperry (1; USNM). Maricopa Co., Tempe, 11 May 1942, A.L. Melander (7, 1; USNM). Pima Co., Organ Pipe National Monument, Alamo Canyon, 16 Apr 1947, A.L Melander (2; USNM); Organ Pipe National Monument, Rincon Spring, 18 Apr 1947, A.L. Melander (5, 4; USNM). Yuma Co., Dateland, 6 May 1948, A.L. Melander (2; USNM); Yuma, 26 Jun 1917, J.M. Aldrich (2; USNM). Squaw Spring, 24 Jul (1; USNM).

California: Alameda Co., Berkeley, 31 Aug 1944, L.W. Quate (1; USNM); Berkeley Hills, 20 Apr 1908 (6, 2; ANSP); Oakland, 11 Jul 1937, M.A. Cazier (1; AMNH). Alpine Co., Hope Valley, 11 Sep 1938, M.A. Cazier (1; AMNH). Calaveras Co., Milton, 21 Oct 1917, J.C. Bradley (2; USNM). Contra Costa Co., Antioch, 25 Jun 1947, A.L. Melander (2; USNM); Jewell Lake, 4 Oct 1947, W.W. Wirth (1, 1; USNM); Pittsburg, 25 Nov 1923, E.P. Van Duzee (1; USNM). Del Norte Co., Smith River, 22 Jun 1932, J.M. Aldrich (1; USNM). Humboldt Co., Trinidad, 18 Sep 1934, A.L. Melander (1; ANSP). Imperial Co., Salton Sea Beach, 30 Apr 1953, J.C. Hall (1; USNM). Inyo Co., Deep Spring, 16 Aug 1953, E.I. Schlinger (1; USNM); Lone Pine, 28 July 1940, R.H. Beamer (2; USNM); Panamint Spring, 15 Aug 1953, E.I. Schlinger (1; USNM). Kern Co., Richbar (5 mi [8 km] S Democrat Springs), 6 Feb 1948, W.W. Wirth (1; USNM). Lake Co., Clear Lake, 18 Jun 1935, A.L. Melander (4, 2; ANSP, USNM). Los Angeles Co., Claremont, C.F. Baker, Metz (2; USNM); El Monte, 8 Jun 1911, P.H. Timberlake (1; USNM); Long Beach, A.L. Melander (5; USNM); Long Beach (Los Angeles River), 18–24 Jun 1952, 1954, M.T. James (3, 1; WSU); Lovejoy Lake, 10 May 1944, A.L. Melander (9, 4; USNM); Malibu Beach, 8 May 1952, A.H. Sturtevant (1; USNM); Pasadena, May–30 Sep 1944, 1949, A.H. Sturtevant (5, 3; USNM, UTA); Rivera, 17 Jun 1889 (1, 3; ANSP); Rosemead, 23 Jun 1943, J. Schuh, K. Gray (1; WSU); Saugus (5 mi [8 km] E), 10 Apr 1953, A.H. Sturtevant (2; USNM); Saugus (10 mi [16 km] NE), 10 Apr 1953, A.H. Sturtevant (1; USNM); Tanbark Flat, 24 Jun 1952, J.K. Hester (1; USNM); Whittier, 5 Jan–5 Oct 1960, A.L. Melander (1, 1; USNM).

Mono Co., Mammoth Lakes, 29 Jul 1940, E.E. Kenaga, L.J. Lipovsky (1, 2; USNM); Mono Lake (NW shore), 12 Aug 1980, R.S. Zack (1; WSU); Topaz Lake, 17 Aug 1951, E.I. Schlinger (1; USNM). Monterey Co., Spreckels, 27 Jun 1916, C.F. Stahl (1; USNM). Orange Co., Buena Park, 19 May 1944, A.L. Melander (3, 2; USNM); Corona del Mar, 27 Aug 1943, A.L. Melander (10, 8; USNM); Green River Camp, Lower Santa Ana Canyon, 9 May 1933, E.P. Van Duzee (1, 1; USNM); Laguna Beach, F.R. Cole (1; USNM). Riverside Co., Andreas Canyon, 31 Mar 1951, A.L. Melander (1; USNM); Burnt Valley, 13 Apr 1989, A. Freidberg (1; USNM); Desert Beach, Salton Sea, 2 Jan 1953, P.H. Arnaud, Jr. (7, 3; USNM); Elsinore, 19 Feb 1950, A.H. Sturtevant (3, 4; USNM, UTA); Elsinore Lake, 25 Jan–21 Nov, 1934, 1935, 1950, A.J. Basinger, S. Fromer, A.L. Melander (36, 31; ANSP, USNM); Indio, 10 Jun 1950, A.H. Sturtevant (1; UTA); Little Lake, 25 Jul 1940, D.E. Hardy (1; USNM); Palm Springs, 4 Mar–18 Nov 1943, 1949, A.L. Melander (5, 8; USNM); Riverside, 18 May–22 Dec 1934, 1935, 1954, 1963, J.C. Hall, N.L.H. Krauss, A.L. Melander (15, 13; ANSP, USNM); Temecula, 4 Apr–27 Jun 1949, 1950, A.L. Melander, W.W. Wirth (4, 1; USNM).

San Bernardino Co., Jenks Lake, 7 Jun–7 Sep 1950, 1954, 1956, A.L. Melander (2, 3; USNM); Mt. Home Canyon, 22 Sep 1953, A.L. Melander (1, 1; USNM); Needles, 10 Mar 1922, J.A. Kusche (1; USNM); Twenty-nine Palms, 29 Aug 1934, P.H. Timberlake (1; USNM); Victorville, 10–22 May 1945, 1952, A.L. Melander, A.H. Sturtevant (3, 2; USNM). San Diego Co., Borrego, 15 Mar–5 May, 1946, 1950, J.L. Sperry (1, 3; USNM); Carlsbad, 1 Jun 1954, J.C. Hall (1; USNM); Desert Edge, 17 Apr 1915, M.C. Van Duzee (1, 1; ANSP, USNM); El Capitan Reserve, 25 Sep 1955, P.H. Arnaud, Jr. (1; USNM); Jacumba Spring, J.M. Aldrich (1; USNM); Lake Henshaw, 10 Mar 1930, A.H. Sturtevant (2; USNM); Lakeside, 4 Aug 1932, J.M. Aldrich (2, 1; USNM); San Diego, 20 Apr–13 Dec 1915, 1916, H.G. Dyer, M.C. Van Duzee (5, 1; ANSP, USNM); Yaqui Wells, 20 Mar 1951, A.H. Sturtevant (1; USNM). San Francisco Co., Golden Gate Park (1; ANSP); San Francisco, 7 Aug–5 Nov 1908, 1925, 1972, F.E. Blaisdell, H.H. Keifer, P. Rubtzoff (1, 2; CAS, ANSP, USNM). San Luis Obispo Co., Oceano Beach, 19 Aug 1948, W.W. Wirth (1; USNM); Oso Flaco Lake, 23 Jun 1948, W.W. Wirth (1; USNM); Paso Robles, 26 Sep 1934, A.L. Melander (1; USNM); San Simon, 14 Sep 1980, A. Freidberg (1, 4; USNM). San Mateo Co., Pescadero (S of), 16 Aug 1951, A.H. Sturtevant (1; USMN); Redwood City, 31 Aug–15 Sep 1959, 1963, P.H. Arnaud, Jr. (2, 3; USNM). Santa Barbara Co., Carpintaria, 3–11 Aug 1950, A.L. Melander (12, 12; USNM); Point Arguello, 23 Aug 1962, R.R. Sanders (2; USNM); Seven Oaks, 18 Sep 1953, A.L. Melander (3, 1; USNM). Santa Clara Co., San Jose, 25 Oct 1967, R.R. Pinger (10, 4; USNM). Santa Cruz Co., Palo Alto, 1 Aug 1957, P.H. Amaud (3; USNM); Santa Cruz (beach and lagoon), 15–17 Jun 1950, M.R. James (3, 3; USNM, WSU). Siskiyou Co., Lower Klamath Lake, 22 Jun 1957, J. Schuh (1; WSU). Stanislaus Co., San Joaquin River, Newman, 15 Jun 1924, J.M. Aldrich (2; USNM). Ventura Co., Hueneme (salt marsh), 17 Jun 1948, W.W. Wirth (2, 1; USNM); Point Mugu, 1 Aug 1952, R.R. Sanders (1; USNM); San Nicolas Island, 13 Sep 1962, R.R. Sanders (1; USNM). Dyerville, 20 Jun 1935, A.L. Melander (1; USNM). Kern River, 28 Aug 1949, A.H. Sturtevant (1; UTA).

Colorado: Boulder Co., Boulder (5500 ft, = 1676 m), 7–17 Aug 1911, 1919, S.A. Rohwer (3, 1; AMNH, USNM). Denver Co., 1 Aug 1939 (3, 1; ANSP, WSU). Garfield Co., Rifle (5400 ft, = 1646 m), 19–21 Jul 1919 (1, 2; AMNH). Jefferson Co., Golden, 17 Jun 1940, A.L Melander (1; USNM). Larimer Co., Fort Collins (on Melilotus), Baker (2; ANSP, USNM); Loveland, 18 Aug 1934, C.W. Sabrosky (1; ANSP). Logan Co., Sterling, 20 Jul 1923, G. Sandhouse (1; USNM). Mesa Co., Grand Junction, 14 Jun 1927, J.M. Aldrich (3; ANSP, USNM). Otero Co., La Junta (4100 ft, = 1250 m), 12 Aug 1920 (3, 1; AMNH); Rocky Ford, 12 Oct 1910, McMillan (1, 1; USNM). Delaware: New Castle Co., Wilmington, 23 Aug 1947 (1; USNM). District of Columbia: Washington, Jun (1; USNM). Florida: Dade Co., Biscayne Bay, A.T. Slosson (1, 1; USNM). Duval Co., Jacksonville, 26 Jun 1957, P.H. Thompson (1; USNM). Hillsborough Co., Tampa, 29 Mar 1933, A.L. Melander (1, 1; ANSP, USNM). Orange Co., Orlando, 5 Feb 1932, A.L. Melander (1; ANSP). Seminole Co., Sanford, 1 Mar 1927, F.M. Uhler (1; USNM). Georgia: Chatham Co., Savannah (privy trap), Mar–Apr 1953, J.W.Kilpatrick (2, 1; WSU). Thomas Co., USPHS, 8 Jun 1948 (3, 3; USNM). Hawaii: Maui: Kanaha Pond, 5 Sep 1970, J.A. Tenorio (2, 1; USNM, WSU). Oahu: Fort Kam, 4 Jul 1944, D.G. Hall (2, 3; USNM); Kailua, Enchanted Lakes, 8 Sep 1969, J.A. Tenorio (1; WSU). Idaho: Latah Co., Moscow, 5–23 Aug 1912, J.M. Aldrich (2; USNM); Troy, Jul 1931 (1; USNM). Nez Perce Co., Lewiston, 12 May–1 Jun, 1901, 1919, A.L. Melander (1, 4; ANSP, USNM). Indiana: Porter Co., Indiana Dunes, 19 Jul 1933, A.L. Melander (1; ANSP). Tippecanoe Co., LaFayette, 21 Aug–5 Sep, J.M. Aldrich (4, 6; USNM).

Kansas: Sedgwick Co., Maize, 29 Jun 1934, C.W. Sabrosky (1; ANSP). Louisiana: St. Landry Par., Opelousas, Mar 1897 (1; USNM). Maryland: Baltimore Co., Hart-Miller Island, 31 May 1987, W.E. Steiner, J.M. Swearingen (2, 2; USNM). Calvert Co., Chesapeake Beach, 2 Aug–17 Nov 1914, 1920, 1923, J.M. Aldrich, J.R. Malloch, R.C. Shannon (7, 4; ANSP, USNM). Prince Georges Co., College Park, 7 Aug 1938, C.T. Greene (1; USNM). Queen Annes Co., Kent Narrows, Jul 1954, M.R. Wheeler (1; USNM). Massachusetts: Bamstable Co., Pocasset, 26 Jul 1950, A.H. Sturtevant (2, 3; USNM). Bristol Co., New Bedford, 26 Aug 1896, Hough (1; USNM). Dukes Co., Pasque Island, 8 Aug 1954, A.H. Sturtevant (1; USNM); Vinyard Haven, 17 Aug 1954, A.H. Sturtevant (1; USNM). Nantucket Co., Nantucket, 21 Sep 1915, A.H. Sturtevant (1; USNM). Minnesota: Anoka Co., Moore's Lake, 14 Jul 1925, C.B. Phillip (1; ANSP). Mississippi: Humphreys Co., Belzoni, 5 Aug, H.S. Barber (1; USNM). Missouri: Boone Co., Columbia, 11 Jul–4 Oct 1967, 1974, W.S. Craig, F.D. Parker (7, 10; USNM).

Montana: Flathead Co., Columbia Falls, 22 Aug 1967, F.D. Parker (1; USNM). Nebraska: Sheridan Co., Hay Springs, 17 Sep 1952, A.H. Sturtevant (1, 1; USNM). Nevada: Churchill Co., Fallon (4000 ft, = 1219 m), 10 Jun 1930, E.L. Bell (1; AMNH). Clark Co., Mesquite, 23 Sep 1980, A. Freidberg (1, 1; USNM). Mineral Co., Walker Lake, 1933, Wickham (several ; ANSP, USNM). Nye Co., Currant, 24 May 1954, M.A. Cazier (1, 1; AMNH). Washoe Co., Pyramid Lake, 16 Jul 1911, J.M. Aldrich (1; USNM); Reno, Sky Ranch, 14 Jul 1952, E.I. Schlinger (1; USNM); Sparks, 18 Jul 1953, E.I. Schlinger (1; USNM); Winnemucca Lake, 17 Jul 1911, J.M. Aldrich (1; USNM).

New Jersey: Camden Co., Cramer Hill, 24 Aug (1; ANSP). Cape May Co., Wildwood, 18 Jul 1908, E.T. Cresson, Jr. (11, 2; ANSP). Essex Co., Newark, Jul 1964 (2; USNM). Monmouth Co., Avon by the Sea, 27 Sep 1908 (1, 1; ANSP). Ocean Co., Manahawkin, 5 Sep 1909 (1; ANSP). New Mexico: Bemalillo Co., Albuquerque, 14 Aug 1947 (3; USNM). Chaves Co., Roswell, Aug, T.D.A. Cockerell (3; USNM). Dona Ana Co., Las Cruces, 13 Jun 1893, 1917, 1950, J.M. Aldrich, T.D.A. Cockerell (4, 3; USNM, UTA). Santa Fe Co., Espanola, 11 Aug–28 Sep 1953, T.D.A. Cockerell, W.B. Heed (1, 1; USNM). New York: Nassau Co., Sea Cliff, N. Banks (1; ANSP). Suffolk Co., Cold Spring Harbor, Jul (1, 1; ANSP, USNM); Hampton Bays, 14 Sep 1953, L. Wilcox (1; USNM); Oak Island, Jul (1; USNM); Orient, 29 Sep 1948, R. Latham (1; USNM); Riverhead, 24 Jul 1933, F.S. Blanton (3; AMNH); Sag Harbor, 4 Aug 1948, R. Latham (1; USNM); Speonk, 26 Sep 1953, L. Wilcox (1; USNM). Westchester Co., Dobbs Ferry, 20 Aug–19 Sep 1958, C. Olsen (1, 1; USNM).

North Carolina: Forsyth Co., (sewer sludge), 15 Aug 1962, C.G. Wright (1, 1; USNM). Guilford Co., Greensboro, 21 Oct 1922, T.D.A. Cockerell (6, 4; USNM). Moore Co., Southern Pines, Apr, A.H. Manee (1; ANSP). Oklahoma: Kingfisher Co., Kingfisher, 13 Sep 1952, A.H. Sturtevant (2; UTA). Oregon: Douglas Co., Umpqua River mouth (3 km S), 11 Oct 1981, L. and I. Cederholm (1; ZIL). Harney Co., Manns Lake (19 mi [30.4 km] SW Oregon route 78), 12 Sep 1981, R.S. Zack (1; WSU). Lake Co., Summer Lake, 28 Jul 1930, H.A. Scullen (1; USNM). Wasco Co., The Dalles, 15 Jun 1938, J. Schuh, K. Gray (1; USNM).

Pennsylvania: Cumberland Co., West Fairview, Jul 1954, M.R. Wheeler (1;UTA). Delaware Co., Swarthmore, 13 Jun 1909, E.T. Cresson, Jr. (1; ANSP). Texas: Cameron Co., Rio Hondo, 15 Feb 1950 (1; UTA). El Paso Co., El Paso, 5 Apr 1902 (2, 1 ANSP). Galveston Co., Galveston, 5 Apr-10 Jun 1900, 1917, J.M. Aldrich, F.H. Snow, W.M. Wheeler (10, 12; AMNH, ANSP, USNM). Hays Co., San Marcos, 8 Nov 1962, A.H. Sturtevant (2, 3; USNM). Hildalgo Co., 26 Jul 1946, H.R. Dodge (1; USNM). Presidio Co., Marfa, 13 Jun 1917, J.M. Aldrich (1 USNM). Travis Co., Austin, 20 Jan-7 Oct 1899, 1901, 1954, W.M. Wheeler (3, 1; AMNH, USNM, UTA). Victoria Co., Victoria, 10 May 1914, F.C. Bishopp (8, 12; USNM). Ardmore Island, 12 Mar 1907, F.C. Bishopp (2 USNM).

Utah: Box Elder Co., Bear River Canyon, 16 Aug 1953, G.F. Knowlton (1; USNM); Brigham City, Bear River Refuge, 23 Jul 1962, K.J. Capelle (1, 1; USNM); Corinne, 16 Aug 1953, G.F. Knowlton (1 USNM); Garland, 25 May 1953, G.F.Knowlton (3; USNM). Cache Co., Wellsville, 28 Aug 1938, G.F. Knowlton, D.E. Hardy (1; USU). Emery Co., Greenriver (3 mi [4.8 km] N, 38°59′N, 110°09′W), 5 Aug 1992, D. and W.N. Mathis (1; USNM). Kane Co., Kanab, 14 Jul 1948, G.F. Knowlton (4, 3 USNM). Millard Co., Delta, 11 Jun 1969, G.F. Knowlton (1; USU); Leamington, 24 Jun 1933, G.F. Knowlton (1; ANSP). Salt Lake Co., Roy, 30 Jun 1927, G.F. Knowlton (2 AMNH). San Juan Co., Blue Creek, 14 Sep 1930, G.F. Knowlton (1; ANSP). Sevier Co., Monroe, 21 Sep 1929, D.E. Fox (l; USNM); Richfield, 27 Jun 1927, G.F. Knowlton (1, 1; AMNH). Utah Co., Goshen Warm Springs (4.3 mi [6.9 km] W Santiquen), 4 Aug 1992, D. and W.N. Mathis (2, 2; USNM); Lehi, 25 Jul 1927, G.F. Knowlton (1; AMNH); Provo, 12–25 Jul 1927, G.F. Knowlton (2; AMNH); Spanish Fork, D.E. Hardy (1, 2; ANSP, USNM). Wayne Co., Hanksville, 2 Jun 1966, G.F. Knowlton (1; USU). Weber Co., Odgen, 1 Aug 1911 (1, 1; USNM); Plain City, 18 Jul 1937, D.E. Hardy (1; ANSP).

Virginia: Accomack Co, Assateague Island, 22 Jul 1967, G.C. Stevskal (1;USNM). Albemarle Co., Greenwood, 17 Oct 1907 (1, 1; USNM). Stafford Co., Potomac Creek, 22 May 1896 (1; ANSP). Washington: Adams Co., Columbia National Wildlife Refuge, Black Lake (1.5 mi [2.4 km] S, alkalie pond), 30 Jul 1978, R.S. Zack (2, 4; WSU); Columbia National Wildlife Refuge, Lower Crab Creek near Black Lake, 28 Aug 1980, R.S. Zack (3; WSU); Lind, 18 Aug 1919, F.W. Carlson (1; WSU); Othello (3.2 mi [5.1 km] W, farm pond), 22 Jun-23 July 1978, 1992, D. and W.N. Mathis, R.S. Zack (9, 3; WSU, USNM); Washtucna (12 mi [14.4 km] W), Sand Hills County Park, 29 Jul-10 Sep 1977, 1978, R.S. Zack (5, 2; WSU). Asotin Co., Asotin, (3; USNM); Clarkston, 8 Jun 1924, A.L. Melander (1; USNM). Benton Co., Kennewick, 7 Jun 1916, A.L. Melander (4, 3; ANSP, USNM); Plymouth (7 mi [11.2 km] W, irrigation pond), 9 Jul 1978, R.S. Zack (2, 2 WSU); Prosser, 14–23 Apr 1948, E.C. Klostermeyer (1, 1; WSU); Richland, 10 Apr-19 Jun 1954, 1974, M.T. James, N.E. Woodley (3, 1 WSU). Chelan Co., Chelan, Siwash, Wapato's shore, 25 Jun 1918, A.C. Burrill (3 WSU). Clallam Co., Blyn, 10 Aug 1921, A.L. Melander (1; ANSP); Dungeness, 24 Aug 1910 (2, 1 ANSP, USNM); Port Angeles, 8 Feb 1951 (1; UTA). Clark Co., Vancouver Lake (5–7 km E Vancouver), 1 Jul 1988, W.N. and D. Mathis (2; USNM). Franklin Co., Eltopia (7 mi [11.2 km] WSW), 1975, W.N. Mathis (13, 4; USNM); Lake Kahlotus (46°39′N, 118°32′W), 25 Jul 1992, D. and W.N. Mathis (4, 2; USNM); Pasco (2 mi E [3.2 km]), 3 Aug 1972, W.N. Mathis (5, 2; USNM); Ringold (Columbia River), 2 Jul 1988, W.N. and D. Mathis (2, 3; USNM); Ringold (Columbia River, 3 km N), 2 Jul 1988, W.N. and D. Mathis (2, 2; USNM); Sacajawea State Park, 12 Jul 1988, W.N. and D. Mathis (3, 4; USNM). Garfield Co., Lower Granite Dam (4 mi [6.4 km] NW, sand dunes), 9 Aug 1983, W.J. Turner (2, 1; WSU).

Grant Co., Columbia National Wildlife Refuge, Migrane Lakes, 16 Jun 1978, R.S. Zack (l, 2; WSU); Columbia National Wildlife Refuge, Soap Lake, 16 Jun 1978, W.J. Turner (2; WSU); Columbia National Wildlife Refuge, Warden Lake, 16 Aug 1977, R.S. Zack (1, 2; WSU); Coulee City, 3 Sep 1920, R.C. Shannon (l USNM); Royal City, 6 Oct 1968, R.C. Sanders (1; USU); Royal City (5.1 mi [8.2 km] W, irrigation pond), 13 Jul 1978, R.S. Zack (3, 1; WSU); Soap Lake, 24 Jul-22 Aug, 1922, 1924, A.L. Melander (11, 6; ANSP, USNM); Soap Lake (N shore, 47°26′N 119°15′W), 23 Jul 1992, D. and W.N. Mathis (4, 4; USNM). Jefferson Co., Quilcene, 16 Aug 1910 (1; USNM). Kittitas Co., Vantage, 8 May 1951 (1; UTA). Klickitat Co., Glenwood, Klickitat River, 17 Jun 1917, A.L. Melander (3; ANSP, USNM). Lincoln Co., Fishtrap Lake, 8 Jul, J.M. Aldrich (2 USNM); Lake Lenore (N end, 10 mi [16 km] N Soap Lake), 23 Jul 1983, R.S. Zack (4, 2; WSU). Okanogan Co., Soap Lake (11 mi [17.6 km] SW Okanogan), 23 Jul 1983, R.S. Zack (3, 1; WSU). Pend Oreille Co., Indian Island near Furport, 23 Jun 1982, R.S. Zack (1 WSU). Pierce Co., Mt. Rainier National Park, Longmire's Spring, 2 Aug 1905 (l; USNM). San Juan Co., Olga, 26 Jul 1909 (l, 1; ANSP, USNM). Walla Walla Co., Lowden, 22 Jun 1921, A.L. Melander (1; USNM). Whitman Co., Almota, 24 Jun-15 Oct 1977, 1978, A.L. Melander, R.S. Zack (3, 1; USNM, WSU); Almota (Almota Creek, 650 ft (= 198 m), on Solidago occidentalis), 10 Sep 1975, W.J. Turner (1; WSU); Kamiac Butte (1; ANSP, USNM); Pullman (pig excrement), 1955, M. Coffey (2, 1WSU); Pullman (stream 5 mi [8 km] SW), 18 Aug 1978, R.S. Zack (3 WSU); Riparia, 8 Apr 1908 (1; USNM); Rock Lake (S shore), 25 Jun 1982, R.D. Akre, R.S. Zack (1; WSU); Wawawai, 7 Apr 1954, M.T. James, J. Quist (1; WSU). Yakima Co., Toppenish, 19 Jun 1923, A.L. Melander (1, 2; ANSP, USNM); Yakima, J.M. Aldrich (6 3; ANSP, USNM).

DISTRIBUTION (Figure 56).—NEW WORLD. Nearctic: Canada (BC), USA (AL, AZ, CA, CO, DC, DE, FL, GA, ID, IN, KS, LA, MA, MD, MN, MO, MS, MT, NB, NC, NJ, NM, NV, NY, OK, OR, PA, TX, UT, VA, WA). Neotropical: Ecuador, Guatemala, Mexico (BCN, BCS, CHI, CHU, JAL, MEX, OXA, SON, VRC), Peru. Oceanian: Hawaii (Maui, Molokai, Oahu).

NATURAL HISTORY.—We suspect that the occurrence of this species on the Hawaiian Islands is adventive, probably through commerce from the West Coast of North America.

DIAGNOSIS.—This species is distinguished from related congeners, especially those from the Western Hemisphere, by the following combination of characters: face, including antennal grooves, extensively microtomentose; parafacial with 1 vertically elongate microtomentose area that is obtusely pointed ventrally, length subequal to combined length of antennal segments; posterodorsal portion of anepisternum with sparse microtomentum, inconspicuous; scutellum bearing 4–5 setae on each side that arise from basal tubercles; 5th tergum with dorsomedial area densely microtomentose.

DISTRIBUTION.—Old World in the Palearctic and Afrotropical regions. Apparently lacking, perhaps secondarily, in the Oriental, Australasian, and Oceanian regions.