Lamproscatella lattini Mathis 1979

Lamproscatella (Thinoscatella) lattini

Scatella (Lamproscatella) quadrisetosa.—Sturtevant and Wheeler, 1954:176 [review, misidentification in part].—not Becker, 1896:229.

Lamproscatella quadrisetosa.—Wirth and Stone, 1956:475 [key, distribution in California, misidentification].—Wirth, 1965:756 [catalog, misidentification in part].—not Becker, 1896:229.

DIAGNOSIS.—Structures of the internal male terminalia are the only characters I have discovered to distinguish specimens of this species from its congener L. quadrisetosa. The ventral extension of the gonite is concave apically, appearing as a shallow bowl, and the apex is slightly swollen (Figure 33).

DESCRIPTION.—Small to moderately small shore flies, length 1.86 to 2.85 mm (averaging 2.43 mm); generally olivaceous brown to dark brown, but with some faintly gray areas, particularly on head.

Head (Figures 26–29): Head width-to-height ratio averaging 1:0.60; conformation of mesofrons trapezoidal, lateral margins narrowing anteriorly, shiny with metallic bronze luster, bearing 2–3 small, generally inconspicuous setae anterior of ocellar triangle; ocellar triangle and fronto-orbital plate concolorous, pollinose to subshiny, brownish; remainder of parafrons mostly charcoal gray. First and third fronto-orbital setae much reduced, subequal in length to each other; second and fourth bristles well developed; all fronto-orbital setae aligned with each other and oriented in same direction. Antenna pubescent, coloration brown to black; arista subequal in length to combined length of first 3 segments, micropubescent to bare. Face subshiny to pollinose, becoming more pollinose ventrally, coloration mostly olivaceous brown, but becoming grayer toward venter and in antennal fovae; 3–4 marginal facial setae in line decending from interfoveal carina, length of these approximately equal to setae along oral margin, several smaller setae on centralized portion of face which extend ventrally and laterally from interfoveal carina. Eye width-to-height ratio averaging 1:0.94; eye-to-cheek ratio averaging 1:0.42; anterior portion of gena and parafacial areas unicolorous, distinctly lighter in color than face, grayish white, becoming darker posteriorly; mouthparts pollinose, brown, with several evenly distributed small setae.

Thorax: Mesonotum pollinose to subshiny, mostly unicolorous, olivaceous brown to grayish brown, more pollinose toward anterior margin; scutellum shinier than mesonotum and slightly darker in color. Pleural areas mostly unicolorous, olivaceous brown but with some lighter colored areas around margins. Femora greenish brown, concolorous, tibiae and tarsi dark brown to black, becoming darker toward apices. Halter pale yellow apically. Costal vein ratio averaging 1:0.16; M1+2 vein ratio averaging 1:0.70.

Abdomen: Dorsum mostly unicolorous, subshiny, olivaceous brown, but slightly lighter colored than mesonotum. Structures of male terminalia as in diagnosis and Figure 33.

TYPE MATERIAL—Holotype male is labeled: “WASH, Pierce Co. Tacoma Environs 25 May 1971 Wayne N. Mathis/HOLOTYPE Lamproscatella lattini W. N. Mathis [red, handwritten].” Allotype female and 38 paratypes (21 , 17 ; USNM) have same label data as holotype. The holotype and paratypes are in the National Museum of Natural History, Smithsonian Institution, Washington, D. C., type number 75957.

OTHER SPECIMENS EXAMINED.—CANADA: BRITISH COLUMBIA: Comox, 24 Jun 1933, J. McDunnough (1 , 1 ; CNC), Vancouver, 8 Aug 1917, A. L. Melander (4 ; USNM); Vancouver Island, Cowichan Bay, 11–12 July 1924, A. L. Melander (5 , 5 ; USNM), Deep Bay, 16 Jun 1955, R. Coyles, (1 ; CNC), Elk Lake, 11 Jul 1924, A. L. Melander (1 ; USNM), Ladysmith, 13 Jul 1924, A. L. Melander (1 ; USNM), Mill Bay, 11 Jul 1924, A. L. Melander (2 ; USNM). UNITED STATES: ALASKA: Anchorage, 20 Jul 1921, J. M. Aldrich (3 ; ANSP, USNM); Cape Thompson, 29 Jul 1961, B. S. Hemming (1 ; CNC); Haines, 14 Jul 1971, B. A. Foote (4 , 2 ; KSU, USNM); Homer, 31 Jul 1954, C. P. Alexander (5 , 1 ; USNM); Hukok Bay, 10 Jul 1953, W. C. F. (1 ; WSU); Kotzebue, 26 Jun 1951, R. I. Sailer (3 , 1 ; USNM); Matanuska, 7 Jun 1944, J. C. Chamberlain (1 ; USNM); Seward, 24 Jul 1921, J. M. Aldrich (4 6 ; USNM); Unakleet, 7 Aug 1951 (1 ; USNM); Valdez, 3–4 Jul, 14 Jul, 3 Aug, 1947–48, 1971, A. H. Storm, R. I. Sailer, B. A. Foote (22 , 18 ; KSU, USNM). CALIFORNIA: Alameda Co., Alameda, 26 May 1915, M. C. VanDuzee (1 , 4 ; CAS), Albany Bay, 26 Sep 1947, Albany Bay, 26 Sep 1947, W. W. Wirth (2 , 4 ; CAS, USNM), Berkeley, 12 May–22 Nov, 1915–1968, M. C. VanDuzee, R. S. Lane (4 , 5 ; CAS); Contra Costa Co., Richmond, 28 Dec 1947, W. W. Wirth (1 ; USNM); Los Angeles Co., Los Angeles, 28 Feb 1915, M. C. VanDuzee (2 ; CAS); Marin Co., Bolinas, 1971, G. Page (1 , 1 ; USNM), Muir Beach, 6 Aug 1950, A. L. Melander (2 ; USNM), Point Reyes, 2 Oct–21 Nov, 1947–1957, W. W. Wirth (4 ; CAS, USNM), Tomales, 19 Oct 1947, W. W. Wirth (3 , 3 ; CAS, USNM); Monterey Co., Asilomar, 4 Aug 1950, A. L. Melander (1 ; USNM); Orange Co., Corona del Mar, 2 Mar–11 Jun, 1944–1950, A. L. Melander, A. H. Sturtevant (2 , 8 ; USNM), Dana Point, 25 Mar 1953, A. H. Sturtevant (2 ; USNM), Morro Bay, 29–30 Aug 1945, A. L. Melander (36 , 34 ; USNM), Newport Beach, 27 Oct 1928, A. H. Sturtevant (1 , 1 ; USNM), Sunset Beach, 12 Jun 1948, A. L. Melander (2 , 2 ; USNM); San Diego Co., Palm City, 19 Jul 1940, D. E. Hardy (3 ; KU), San Diego, 5 Apr 1915, M. C. VanDuzee (1 , 3 ; CAS); San Luis Obispo Co., Laguna Beach 25 Mar-15 May, 1946–1947, A. L. Melander (4 , 1 ; USNM), Morro Dunes, 6 Sep 1945, A. L. Melander (1 ; USNM); San Mateo Co., Dumbarton Bridge, 30 Jul 1947, W. W. Wirth (2 , 3 ; USNM); Santa Barbara Co., Carpinteria, 9 Oct 1946, A. L. Melander (1 , 1 ; USNM); Santa Clara Co., Palo Alto, 10 Jul–11 Aug, 1911–1917, J. M. Aldrich (1 , 3 ; USNM); Santa Cruz Co., Big Basin, 18 Jul 1954, A. L. Melander (4 , 5 ; USNM), Capitola, 7 Apr 1956, P. H. Arnaud (1 , 1 ; CAS), Santa Cruz, 3 Jan 1948, W. W. Wirth (1 ; USNM); Sonoma Co., Bodega Bay, 16 Apr–19 Oct, 1947–1964, W. W. Wirth, J. D. Birchim (7 ; CAS, USNM); Ventura Co., Hueneme, 17 Jun 1948, W. W. Wirth (6 ; USNM), Point Mugu, 20 Jul 1962, R. R. Saunders (7 , 5 ; ISU, USNM). OREGON: Clatsop Co., Fort Stevens State Park, 26 Jun 1963, R. C. Dickson (1 ; UCR), Seaside, 23 Aug 1951, A. H. Sturtevant (1 , 7 ; USNM); Coos Co., Coos Bay, 8 Aug 1940, A. L. Melander (1 ; USNM); Lincoln Co., Boiler Bay, 9 Mar 1930, J. Wilcox, (4 , 5 ; ANSP), Lincoln Beach, 26 Jun 1971, G. Steyskal (1 ; USNM), Waldport, Alsea Bay, 9 Oct 1971, W. N. Mathis (14 , 25 ; USNM); Tillamook Co., Neskowin, 10–17 Aug 1948, M. T. James (2 , 1 ; WSU), Sand Lake, 3.2 km S, 13 Jun 1972, W. N. Mathis (1 ; USNM). WASHINGTON: Clallam Co., Blyn, 10–24 Jul, 1917–1921, A. L. Melander (13 , 13 ; USNM), Crescent Bay, 26 Jul 1917, A. L. Melander (1 , 1 ; USNM), Sequim, 25 Aug 1951, A. H. Sturtevant (1 ; USNM); Grays Harbor Co., Copalis, 25 Aug 1951, A. H. Sturtevant (1 ; USNM), Hoquiam, 26 Aug 1951, A. H. Sturtevant (1 , 1 ; USNM); Jefferson Co., Brinnon, 11 Aug 1921, A. L. Melander (3 ; USNM), Fort Warden near Point Townsend, 15 Jun 1971 (1 , 1 ; WSU); King Co., Seattle, 2 Aug 1908 (2 ; ANSP, USNM); Mason Co., Dewatto, 15 Aug 1910 (1 , 2 ; USNM), Shelton, Walkers Park, 21 Jul 1917, A. L. Melander (1 ; USNM); Pacific Co., Fort Canby, 8 Aug 1975, W. N. Mathis (1 ; USNM), Ilwaco, 28 Jun–12 Jul, 1922–1924, A. L. Melander (6 ; 7 ; USNM), Kickerville, gulf, 5 Sep 1954, J. J. Davis (2 ; WSU), Nahcotta, 14 Jul–24 Aug, 1953–1960, M. T. James (37 , 40 ; USNM, WSU), Naselle, 13 Jul 1922, A. L. Melander (5 , 5 ; USNM), Ocean Park, 23 Jul–18 Aug, 1950–1961, M. T. James (9 11 ; WSU), Raymond, 15 Feb 1971, W. N. Mathis (1 , 7 ; USNM), South Bend, 23 May 1917, A. L. Melander (1 ; USNM), Tokeland, 18 Jul 1917, A. L. Melander (9 , 5 ; USNM); Pierce Co., Gig Harbor, 17 May–26 Jul 1971, W. N. Mathis (35 , 44 ; USNM), Tacoma, 18 May–27 Aug 1971, W. N. Mathis (39 , 41 ; USNM); San Juan Co., Friday Harbor, 25 Jun–1 Aug, 1909–1930, A. C. Hodson (36 , 72 ; ANSP, MCZ, UMN, USNM); Snohomish Co., Everett, 20 Jun 1920, A Spuler (1 ; WSU); Thurston Co., Olympia, South Bay, 3 Jul 1925, A. L. Melander (1 , 4 ; USNM); Whatcom Co., Birch Bay, 11–15 Jul 1949, M. T. James (31 , 14 ; WSU), Larabee State Park, Bellingham, 17 Jul 1949, M. T. James (10 , 5 ; WSU).

GEOGRAPHIC DISTRIBUTION (Figure 30).–The species occur along the west coast of North America between 32° and 67° north latitude.

ETYMOLOGY.—The Latinized genitive patronym lattini honors Dr. John D. Lattin, who furthered my interest in entomology and made its study pleasant.