Notiphila atripes Cresson 1917

Notiphila (Dichaeta) atripes Cresson

Notiphila (Agrolimna) atripes Cresson, 1917:50.

TYPE-MATERIAL.—Holotype male: “15-6-(18)76 Beverly. Mass(achusetts). Burgess (collector?)//Type No. 20726 U.S.N.M. (red)/Holo-TYPE Notiphila atripes E. T. Cresson Jr (red).” The original description also listed two female paratopotypes.

DIAGNOSIS.—Externally, members of N. atripes are quite similar to those of N. quadrisetosa and N. uliginosa, and they have often been confused with both of the latter species. Specimens of N. atripes may be distinguished from these and other congeners by the following characters: Antenna, maxillary palpus, and legs entirely black; mesonotum and mesopleuron usually immaculate but exceptions with vittate markings; fascia of abdominal terga dark brown to black, usually extensive, often covering entire dorsum of fourth and fifth abdominal terga; ventral margin of hypandrial process sinuate; shape of preapical enlargement and surstyli distinctive (Figures 139–142).

DESCRIPTION.—Moderately small to moderately large shore flies, length 2.56 to 4.10 mm; with light brownish gray to gray coloration and dark brown to black markings.

Head: Head ratio 1:0.73; postfrons ratio 1:0.56; frons with median triangular area and lateral margins concolorous but not too distinct from remainder of frons; extreme anterolateral margins in some specimens light gray. Paravertical bristle just slightly larger than biggest postocellar bristles; 2 pair of proclinate, fronto-orbital setae. Antennal segments entirely black; arista with 8–12 dorsal branches. Face yellowish gray; prefrons ratio 1:0.64; facial setae small, hairlike. Eye ratio 1:0.81; eye-to-cheek ratio 1:0.20; gena narrow, gray except for anterior portion, which is concolorous with face; genal bristle distinct. Maxillary palpus black.

Thorax: Generally unicolorous, mostly gray, although mesonotum is usually darker, brownish gray. Mesonotum and mesopleuron immaculate. Legs entirely dark, usually black although hind tarsomeres paler, yellowish in a few specimens; setal fascicle of hind basitarsus pale, amber. Wing ratio 1:0.43; costal vein ratio 1:0.57; M1+2 vein ratio 1:1.1.

Abdomen: Abdomen ratio of males 1:0.79; length of fourth tergum to fifth tergum ratio of males 1:1.4; fifth tergum ratio of males 1:0.56. Fascia of abdominal terga dark brown to black, distinctly contrasting with background coloration, especially on third and fourth terga; sometimes entire tergum of fourth and fifth segments is unicolorous, dark brown to black. Terminalia of males as in diagnosis and Figures 139–142.

SPECIMENS EXAMINED (1120).—CANADA: ALBERTA: Carmangay-Little Bow River (USNM); Sheep River (USNM); Banff (CNC, CAS); Jasper (CNC); Kannanakis (CAS); Scandia (CNC). BRITISH COLUMBIA: Clinton (CNC). MANITOBA: Birtle (AMNH); Warkwork Creek, near Churchill (CNC); Whitewater Lake (CNC). NORTHWEST TERRITORIES: Norman Wells (CNC). NOVA SCOTIA: Baddeck-Cape Breton (MCZ); English Town-Cape Breton (MCZ); Loua-Cape Breton Island (MCZ); Saint Ann-Cape Breton Island (MCZ); Petite Riviere (CNC). ONTARIO: Ottawa (ANSP, CNC). QUEBEC: Gaspe (AMNH, USNM); Gaspe-Anse Au Griffon (ANSP, USNM); Montreal (AMNH). SASKATCHEWAN: Attons Lake-Cut Knife (CNC); Lisieuz (CNC); Val Marie (CNC). YUKON TERRITORY: Whitehorse (CNC). UNITED STATES: CALIFORNIA: Eldorado Co., Fallen Leaf (CNC); Inyo Co., Bishop (KU), Death Valley Floor near Furnace Creek (ANSP), Deep Springs (UCB); Lassen Co., 35.4 km NW Susanville (WNM); Mariposa Co., Yosemite National Park (KU); Modoc Co., Alturas (WNM); Mono Co., 30.6 km NW Benton (WNM), Convict Creek (UCB, USNM), Fales Hot Spring (USNM), Mono Lake (USNM, WNM), 3.2 km N Mono (WNM); Nevada Co., Hobart Mills near Sage Hen (UCD), 4 km NW Hobart Mills (WNM); Placer Co., Lake Tahoe (USNM); San Luis Obispo Co., Alamo Creek (UCB); Shasta Co., Moose Camp (UCD); Trinity Co., Trinity River Camp (UCD); Tulare Co., 24.2 km NE California Hot Springs (WNM). COLORADO: Lindland (ANSP, CSU, WSU); Shaffers Crossing (ANSP, CSU); Boulder Co., Nederland (CNC, KU); Chaffee Co., Buena Vista (CNC), Poncha Springs (ANSP, CSU); Clear Creek Co., Idaho Springs (CSU); Dolores Co., 10.5 km W Dove Creek (WNM); Gilpin Co., East Portal (CNC); Hinsdale Co. (KU); Jackson Co., Gould (USU), Walden (USU); Jefferson Co., Golden (USNM); Lake Co., Tennessee Pass (KSU); La Plata Co., Electra Lake (WNM), Hesperus (WMN); Larimer Co., Fort Collins (ANSP, CSU, WSU), La Porte (CSU), Virginia Dale (MSU, USNM); Mesa Co., Glade Park (USNM); Montezuma Co., 12.9 km W Cortez (WNM); Park Co., Fairplay (WSU), Hartsel (USNM); Pitkin Co. (KNSU); Teller Co., Florissant (CAS); Weld Co., Roggen (WSU). IDAHO: Big Lost River-Salmon River Road Pass (ANSP). IOWA: Dickinson Co., Excelsior Fen (ISU); Polk Co., Clive (USNM). MASSACHUSETTS: Essex Co., Beverly (ANSP, USNM). MICHIGAN: Midland Co. (ANSP, MSU). MINNESOTA: Polk Co. (UMN). MONTANA: Flathead Co., 1.6 km W Bigfork (KSU), 3.2 km Bigfork (KSU), NW Bigfork (KSU), 16.1 km NW Bigfork (KSU); Glacier Co., 3.2 km E Babb (KSU, USNM), 37 km E Babb (KSU), NW Browning (KSU); Lake Co., 4.8 km E Polson (KSU), 6.4 km E Polson (KSU, USNM), 12.9 km NE Polson (USNM); Powell Co., Deer Lodge and vicinity (CU). NEBRASKA: Blaine Co., Dunning (MSU); Box Butte Co., Alliance (UN); Dawes Co., Marsland (UN, USNM); Morrill Co., Bayard (UN, USNM); Sheridan Co. (MSU). NEVADA: Elko Co., Wells (ANSP, CSU); Washoe Co., Reno (CAS). NEW MEXICO: Catron Co., 51.5 km E Glenwood (WNM); Otero Co., Cloudcroft (KU, USNM); Sandoval Co., Seven Springs Ranger Station (WNM), 17.7 km SE Cuba (WNM), 12.1 km N Jemez Springs (WNM); San Miguel Co., 0.8 km NE Montezuma (WNM). OREGON: Deschutes Co., 4.8 km SE La Pine (WNM); Grant Co., 0.8 km S Seneca (WNM); Harney Co., 3.2 km E Burns (WNM), 25.8 km N Burns (WNM), Denio (USNM); Josephine Co., 6.4 km W Selma (WNM); Klamath Co., Wood River Spring (WSU); Lake Co., Hart Mountain Refuge-Hot Spring Camp (WNM), Ana Reservoir (WNM), Hunter Hot Spring (WNM). 7.7 km N Summer Lake (WNM), Warner Canyon (WNM), 31.9 km NW Paisley (WNM), NW shore Alkali Lake (WNM); Union Co., North Powder (KU). SOUTH DAKOTA: Lake Oakwood (ANSP); Bennett Co., Martin (ANSP); Custer Co., Custer (ANSP), 11.3 km W Custer (WNM); Lawrence Co., 1.6 km W Savoy (WNM), 3.2 km W Savoy (WNM); Lincoln Co., Canton (ANSP); Tripp Co., Winner (ANSP). UTAH: Allen Canyon (CNC); Gooseberry (ISU); Sawtooth (ISU); Soldier Springs (UMN); Willow Creek Canyon (KU, UMN); Beaver Co., Beaver (UMN); Box Elder Co., Mantua (ISU); Carbon Co., Soldier Canyon (WNM), S Price (WNM); Cache Co., Logan (UMN), Logan Canyon (CNC, USU), Blacksmith Fork (USU), Richmond (UMN), Trenton (UMN); Duchesne Co., Indian Canyon (CU), Ashley National Forest-Lime Kiln Spring (WNM), 8.1 km N Mountain Home (WNM), Hana (UMN); Emery Co., 0.8 km N Castle Dale (WNM); Piute Co., Marysvale (CSU); Rich Co., Garden City (USNM), Lake-town (ISU); Sevier Co., Salina (ISU); Uinta Co., Big Brush Creek, 35.4 km N Vernal (CNC); Utah Co., Provo (UNM); Wasatch Co., Strawberry Reservoir (CNC, KU, UNM), 3.2 km S Daniels Pass (CNC); Washington Co., Leeds (UMN), Saint George (UMN). WASHINGTON: Stevens Co., 24.2 km W Kettle Falls (USNM). WISCONSIN: Dodge Co., Beaver Dam (ANSP). WYOMING: Washakie (MSU); Albany Co., Tie Siding (USNM); Laramie Co., Horse Creek (KU); Niobrara Co., 19.3 km NW Lusk (KU); Teton Co., Hoback (MSU); Uinta Co., 1.6 km NW Evanston (KSU, USNM); Yellowstone National Park, south entrance (UCB), Beach Springs (ANSP, USNM), Twin Lakes (USNM).

GEOGRAPHIC DISTRIBUTION (Figure 143).—Notiphila atripes occurs widely in the West from the Yukon Territory south to southern New Mexico. In the Midwest and East, it is more restricted to the southern Canadian provinces and northern states of the United States. Collection dates are from 5 June to 4 August.