Calyxochaetus sobrinus
Creators: name: Runyon, Justin B.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Dolichopodidae
Calyxochaetus
Calyxochaetus sobrinus

description: Calyxochaetus sobrinus (Wheeler)
(Figs 108, 117, 124, 145)
Nothosympycnus sobrinus Wheeler, 1899: 54.
Nothosympycnus inornatus Van Duzee, 1917: 340 syn. nov.
Calyxochaetus sobrinus: Parent (1930: 107).
Calyxochaetus inornatus: Parent (1930: 107).
Sympycnus hastatus Van Duzee, 1930: 57 syn. nov.
Calyxochaetus hastatus: Foote et al. (1965: 528).
Type material examined. Nothosympycnus sobrinus: HOLOTYPE ♂, labeled: “Lewiston/ Idaho ”; “ W. M. Wheeler / Collection.”; “Type” (AMNH).
Nothosympycnus inornatus: LECTOTYPE (designated here to fix identity of the species) ♂, labeled: “ Wild Cat Cn. San Pablo / Contra Costa Co. Cal. / Nov 16, 06 J. C. Bradley ”; “MCVan Duzee/ Collection”; “ Nothosympycnus / inornatus / Paratype.VanDuzee”; “ ♂ ”; “ LECTOTYPE / Calyxochaetus / inornatus (Van Duzee) / des. J.B. Runyon [blue label]” (CAS).
Sympycnus hastatus: HOLOTYPE ♂, labeled: “ San Diego Co. / Desert edge/ Cal. Apr. 15 ‘15/ MCVan Duzee”; “ Calyxochaetus / hastatus / Holotype.VanDuzee”; “ California Academy/ of Sciences/ Type No. 3529” (CAS).
Other material examined. CANADA: British Columbia: Vancouver Island, Parksville, Englishman River, N49°19.00′ W124°17.07′, 21.viii.2008, S.E. Brooks (1♂, CNC). MEXICO: Baja California: Sierra San Pedro Martir, La Zanja, 6800 ft, 11.vi.1953, P.H. Arnaud, Jr (1♂, CAS); same data except, trail from La Joya to La Zanja, 10.vi.1953 (2♂, CAS); same data except, La Grulla, 6500 ft, 29.v.1958, J. Powell (1♂, EMEC). USA: California: Alameda County: Berkeley, viii.1915, ALM (1♂, USNM); Alpine County: Indian Creek Reservoir, 15.vi.1979, G.E. Bohart (7♂, 9♀, LACM); 8 mi. W Markleeville, 15.vi.1979, G.E. Bohart (2♀, LACM); Grover Hot Springs State Park, near Hoffman House, 38°41.997′N 119°50.805′W, 1800 m, Malaise, 25.v–8.vi.2006, P.H. Kerr & S.L. Winterton (1♂, CSCA); Contra Costa County: Mt. Diablo, 11.v.1952, E.I. Schlinger (4♂, UCD); same data except, 12.x.1952 (1♀, UCD); Richmond, Point Molate, 20.ii.1975, J. Powell (1♂, EMEC); Del Norte County: Crescent City, 10.vii.1930, J.M. Aldrich (1♂, USNM); Smith River, Rowdy Creek, 11.vii.1930, J.M. Aldrich (1♂, USNM); Gasquet, 20.vi.1974, P.H. Arnaud, Jr (1♂, CAS); 7.5 mi. N Gasquet, 31.viii.1986, RLH (1♂, 5♀, MTEC); El Dorado County: 4 mi. S Somerset, 31.v.1954, E.I. Schlinger (2♂, 1♀, CAS); Humboldt County: Bolling Park, 19.vi.1935, ALM (1♂, USNM); Humboldt State University, Arcata, 23.v.1987, RLH (1♂, 3♀, MTEC); Luffenholtz Creek at Luffenholtz Beach, 24.ix.2000, RLH & JBR (1♂, MTEC); Kern County: 1 mi. E Woody, 3.v.1964, P. Rude (1♂, EMEC); Los Angeles County: Los Angeles, Griffith Park, 3.vi.1945, ALM (1♂, USNM); Santa Catalina Island, Middle Canyon, 500–750 ft, 1–2.v.1978, M.E. Buegler (2♂, 1♀, EMEC); Madera County: San Joaquin Experiment Station, 22.ii.1953, P.D. Hurd (2♂, EMEC); Marin County: 7 mi W Fairfax, 23.vii.1951, W.C. Bentinck (1♂, EMEC); Lilly Lake, 213 m, 17.ix.1972, P.H. Arnaud, Jr (2♂, CAS); Mariposa County: Yosemite, 3880–4000 ft, 19.v.1938, K.D. Snyder (1♂, EMEC); Mendocino County: 6 mi. W Willits, 30.vi.1951, W.C. Bentinck (1♂, EMEC); Hopland Field Station, Kelsey Meadow, 2400 ft, sweeping mossy seepage, 14.v.1977, J. Powell (2♂, EMEC); Dunlap campground, 29 km W Willits, 12–13.vii.1969, P.H. Arnaud, Jr (3♂, CAS); Monterey County: Pacific Grove, beach, 6.v.1906, J.M. Aldrich (1♂, USNM); Big Sur, 28.vii.1940, ALM (2♂, USNM); Pfeiffer Big Sur State Park, 16.vi.1949, P.H.Arnaud, Jr (2♂, CAS); Indians Guard Station, 17 air mi NW Jolon, 2100 ft, 9.v.1975, E. Rogers (1♂, EMEC); Paraiso Hot Springs, 400 m, 29.v.1977, P.H.Arnaud, Jr (1♂, CAS); Escondido campground, 22.v.1976, D.D. Wilder (1♂,CAS); Antonio River below Escondido, 22.v.1977, D.D. Wilder (3♂, CAS); Arroyo Seco campground, 26.iv.1998, M. & P.H. Arnaud, Jr (1♂, USNM); Nevada County: Sagehen campground, N39°26′00.3″ W120°15′24.6″, 11.vii.2012,S.H. Cumming(1♂,CNC); Carpenter Ridge, cirque lake, N39°24′54.2″ W120°18′41.8″, 13.vii.2012, S.E. Brooks (1♂, CNC); Prosser Creek at Hwy 89, N39°23′50.2″ W120°11′13.9″, 14.vii.2012, S.E. Brooks (1♂, CNC); Placer County: Bear Valley, 1 mi. N Emigrant Gap, 5.vi.1970, J.T. Doyen (2♂, 1♀, EMEC); Riverside County: Cathedral Canyon, 31.xii.1945, ALM (2♂, USNM); Ortega Highway, El Cariso campground, 26.v.1944, ALM (1♂, USNM); Ortega Highway, Mariana River, 16.vii.1945, ALM (1♂, 1♀, USNM); Mount San Jacinto, 10.v.1935, ALM (1♂, USNM); Palm Springs, 20.xi.1943, ALM (1♂, USNM); Idyllwild, 7.vi.1942, ALM (2♂, USNM); Palm Canyon, 25.xii.1952, P.H. Arnaud, Jr (1♂, 1♀, CAS); same data except, 13.i.1953 (1♀, CAS); San Bernardino County: Barton Flat, South Fork campground, 31.viii.1944, ALM (1♂, 2♀, USNM); Upper Santa Ana River, 21.v.1958, ALM (1♂, USNM); Sugarloaf Mountain, 15.vii.1946, J.L. Sperry (2♂, USNM); same data except, Cienaga, 11.v.1947 (1♂, USNM); Oak Glen, 2.vii.1945, ALM (1♂, USNM); Wrightwood, 24.v.1945, ALM (1♂, USNM); Mill Creek Canyon, 9.vi.1924 (1♂, EMEC); Mill Creek Canyon, 17.vii.1924 (3♂, 1♀, EMEC); San Bernardino Mts, 3 mi. E Seven Oaks, 5900 ft, 19.v.1981, E. Fisher (3♂, 4♀, CSCA); 6 mi E Seven Oaks, tributary of Santa Ana River, N34°10′14.5″ W116°49′47.3″, 1912 m, 11–12.vi.2016, S.E. Brooks (4♂, 5♀, CNC); same data except, J.M. Cumming (2♂, 3♀, CNC); 2.6 mi. E Seven Oaks, Santa Ana River, N34°11′0.1″ W116°52′12.1″, 1770 m, 11–12.vi.2016, S.E. Brooks (1♂, 4♀, CNC); same data except, J.M. Cumming (3♀, CNC); San Diego County: Alpine, 8.iv.1915, M.C. Van Duzee (1♂, CAS); same data except, 12.iv.1915 (1♂, CAS); Desert edge, 15.iv.1915, M.C. Van Duzee (3♂, CAS); San Diego, 28.iii.1916, H.G. Dyar (1♂, USNM); Lakeside, 20.iii.1940, FCH (1♂, FSCA); Palomar Mountain, 14.vi.1948, ALM (4♂, USNM); San Luis Obispo County: Morro Bay, 27.vii.1940, ALM (1♂, USNM); San Mateo County: Headwaters of Pescadero Creek, 19.x.1946, P.H. Arnaud, Jr (3♂, CAS); Redwood City, vi.1954, P.H. Arnaud, Jr (1♂, CAS); 3 mi. W San Mateo, 27.ix.1926, E.H. Nast (1♀, CAS); Corte Madera Creek, Alpine Road, SE Portola, 230 m, 19.ix.1976, P.H. Arnaud, Jr (3♂, 4♀, CAS); Santa Barbara County: Santa Cruz Island, Cañada del Medio, 11.v.1968, R.W. Rust (1♀, UCD); Santa Cruz Island, Prisoner’s Harbor Lagoon, 23.vii.1964, T. Fisher (1♂, CAS); Santa Cruz Island, Cueva Valdez, 31.viii.1980, RLH (2♂, 1♀, MTEC); Santa Clara County: Stanford University, 11.iv.1906, J.M. Aldrich (1♂, USNM); same date except, 27.i.1906 (1♂, USNM); Stanford University, 2.iv.1951, P.H. Arnaud, Jr (1♂, CAS); Almaden Quicksilver County Park, sweeping grasses by water seep, 29.iv.1979, L.G. Bezark (1♂, 2♀, CSCA); same data except, 6.v.1979 (1♂, 1♀, CSCA); Shasta County: Gibson, 14.v.1948, W.W. Wirth (1♂, USNM); Sierra County: North Yuba River, Indian Valley campground, 900 m, 4.vii.1975, P.H. Arnaud, Jr (1♂, CAS); Solano County: Cold Canyon Reserve, 29.x.1983, G.L. Stebbins (4♂, 3♀, UCD); Tulare County: Sequoia Park, 6200 ft, 6.vi.1935, ALM (1♂, USNM); Sequoia National Park, Ash Mountain, 26.iv.1951, E.I. Schlinger (1♂, CAS); Coffee Camp, 5 mi. E Springville, 1.v.1979, R. Coville (1♂, EMEC); Tuolumne County: Pinecrest, 13.viii.1948, P.H. Arnaud, Jr (2♂, 2♀, CAS); Strawberry, 24.vi.1951, A.T. McClay (1♂, CAS); Strawberry, 20.vii.1951, W.C. Bentinck (2♂, 1♀, EMEC); Ventura County: San Nicolas Island, NAS headquarters area, 5.v.1978, J. Powell (1♂, EMEC); Unknown County: Live Oak Park, 24.v.1944, ALM (2♂, USNM); same data except, 7.vi.1945 (2♂, USNM). Idaho: Nez Perce County: Lake Waha, Zaza Road, N46°10.512′ W116°48.264′, 1390 m, ex. small streams, 15.vi.2014, B.J. Sinclair (1♂, CNC); same data except, Flat Iron Road, West Fork Sweetwater Creek, N46°12.412′ W116°49.027′, 1040 m (4♂, CNC). Montana: Lincoln County: Yaak River, N48°33.69′ W115°58.38′, 1875 ft, 23.vii.2016, JBR (1♂, MTEC); Mineral County: Lolo National Forest, Trout Creek Road, 47°02.249′N 114°57.790′W, 1188 m, roadcut seeps, 25.vi.2017, B.J. Sinclair (1♂, CNC). Nevada: Carson City County: Clear Creek campground, 6500 ft, 27.vii.1968, D.D. Munroe (1♂, CNC). Oregon: Benton County: South Fork Alsea River, N44°21′03.6″ W123°34′40.4″, 117 m, 5.vii.2014, S.E. Brooks (3♂, 11♀, CNC); same data except, J.M. Cumming (1♂, CNC); Douglas County: South Myrtle Creek, N43°02′05″ W123°09′54″, 26.v.2009, J.M. Cumming (2♂, CNC); same data except, S.E. Brooks (1♂, CNC); Tenmile, Lower Tenmile Creek, N43°5′27″ W123°34′13″, 27.v.2009, J.M. Cumming (2♂, CNC); same data except, S.E. Brooks (3♂, CNC); Jackson County: Mt. Ashland, 4600 ft, 24.vi.1971, G. Steyskal (1♂, USNM); Linn County: Crawfordsville, 27.vi.1971, G. Steyskal (1♂, USNM); Multnomah County: Latourell Falls, 2.viii.1962, R.A. McHugh & FCH (3♂, FSCA).
Diagnosis. Males can be recognized by the arista-like stylus very slightly widened on apical half or less of article 2 (Fig. 108) and form of the mid tarsus (Fig. 124). This species is related to C. desertus and C. pictipes (see diagnosis for C. desertus).
Redescription. Male. Wing length 2.8–3.3 mm. Similar to C. desertus except as noted: Head: Frons usually with glabrous shiny blue-violet spot on either side of ocellar tubercle but sometimes thinly brown pruinose. Arista-like stylus (Fig. 108) shorter (subequal to head height), very slightly widened on apical half or less of article 2, with apex pointed. Legs: Midleg: Tarsomere 5 3X as long as wide, subequal to combined length of tarsomeres 3–4 (Fig. 124). Abdomen: Tergites 2–3 varying from mostly yellow to wholly brown.
Female. Wing length 2.9–3.4 mm. Similar to C. desertus except arista-like stylus with apex sharply pointed, not blunted. Abdomen: Tergites 2–3 usually wholly brown, sometimes yellow laterally.
Distribution and seasonal occurrence. Far western North America, from northern Baja California, Mexico to Vancouver Island, British Columbia, Canada and a few records in northern Idaho and northwest Montana, USA (Fig. 145). Widespread and common in California. Adults are present year-round near the coast and have been collected in the spring and summer at higher elevations inland.
Remarks. This species is quite variable in the presence/absence of a glabrous shiny frons and the presence and extent of yellow on the abdomen. Van Duzee (1930) separated C. hastatus from C. sobrinus by the size of the enlargement of the arista-like stylus. While there is some variation in size of the enlargement of the arista-like stylus among males of C. sobrinus, the viewing angle is important with the arista-like stylus appearing slender in some views and the full width is visible only at certain angles. Van Duzee (1930) did not include C. inornatus. I can find no differences among the types of these three species and consider them synonyms.
Nothosympycnus inornatus was described “from seven males and several females” (Van Duzee 1917). Only one male lectotype was examined (CAS). All paralectotypes of this species are purportedly deposited in the Cornell University Insect Collection, Ithaca, New York, USA (Pollet et al. 2004) and were not examined.
description: Published as part of Runyon, Justin B., 2024, Revision of the genus Calyxochaetus Bigot (Diptera: Dolichopodidae: Sympycninae), pp. 1-74 in Zootaxa 5539 (1) on pages 68-70, DOI: 10.11646/zootaxa.5539.1.1, http://zenodo.org/record/14240426