Scatophila bipiliaris Sturtevant and Wheeler

Zatwarnicki, Tadeusz & Mathis, Wayne N., 2024, Revision of the Nearctic Species of the Shore-Fly Genus Scatophila Becker (Diptera: Ephydridae), Zootaxa 5487 (1), pp. 1-100 : 68-71

17. Scatophila bipiliaris Sturtevant and Wheeler

Figs. 146 , 149–155 , 159

Scatophila bipiliaris Sturtevant and Wheeler 1954: 187 .— Wirth 1965: 758 [ Nearctic catalog].— Zatwarnicki 1987: 291 [checklist].— Zatwarnicki and Mathis 1994: 365 [phylogeny, quadriguttata group].— Mathis and Zatwarnicki 1995: 281 [world catalog].

Diagnosis.—This species is distinguished from congeners by the following combination of characters: Body most gray with some brown markings; small shore flies, body length 1.35–1.80 mm.

Head ( Figs. 149–152 ): Lateroclinate fronto-orbital seta inserted farther from medial vertical setae than distance between vertical setae; mesofrons tannish gray; Face mostly microtomentose, gray; face of ♂ convex medially, convexity roundish, arched, side bearing cluster of longer setae laterally. Gena-to-eye ratio 0.25–0.31.

Thorax ( Figs. 146 , 156 ): Mesonotum ( Fig. 156 ) mottled, mixture of brown and gray, brown medially, irregular; scutellar disc gray, lateral margins, especially at insertion of scutellar setae brown. Wing ( Fig. 146 ) faintly colored, including spots; costal vein ratio 0.24–0.30; M 1 vein ratio 0.61–0.79. Knob of halter yellow. Legs generally dark colored; femora and tibiae with gray microtomentum; male midfemur lacking row of spine-like setulae along posteroventral margin; tarsi black.

Abdomen ( Figs. 153–155 ): Tergites mostly gray, especially laterally, medial area faintly brown, more so toward anterior margin of tergites 2–3. Male terminalia ( Figs. 153–155 ): Epandrium in posterior view ( Fig. 153 ) generally squatly oval except for broadly truncate ventral margin, width equal to height, lateral margins shallowly and angularly curved, width of ventral margin almost twice width of cercal opening; dorsal margin of epandrium in posterior view ( Fig. 153 ) somewhat broadly rounded, ventral portion of epandrium less wide and straight below bulge, ventral to midheight; epandrial setae about equal in length, sparser medially and laterally, more abundant along ventral margin; height of cercal opening slightly less than half epandrial height; cerci in posterior view ( Fig. 153 ) robustly lunate; aedeagus in lateral view ( Fig. 155 ) narrowly rounded basally, forming irregular U-shaped structure, posterior portion narrowed to narrow, short point, dorsal margin strongly excavated, cavity nearly twice as long as wide, in ventral view ( Fig. 154 ) narrowly oval; ventral aedeagal process sinuous; phallapodeme in lateral view ( Fig. 155 ) very elongate, narrow, roundly angulate at dorsal quarter, length of dorsal portion (toward base of aedeagus) about 1/4 length of ventral portion, ventral portion elongate and linear, mostly parallel sided, slightly tapered to blunt apex, in ventral view ( Fig. 154 ) T-shaped, basal crossbar about 0.4 length of medial process, crossbar distinctly tapered; postgonite in lateral view ( Fig. 155 ) deeply V-shaped, with dorsal extension somewhat rectangular but with nipple-like process at posterodorsal angle, bearing setulae, ventral arm or extension elongate, narrow, slightly tapered, in ventral view ( Fig. 154 with posterior extensions narrowly rod-like and with a nipple-like apex; neohypandrium in lateral view ( Fig. 155 ) elongate, narrow, angulate at right angle, extended, posterior portion curved, becoming slightly wider on apical half, twice length of ventral, rod-like portion.

Type Material.— The holotype male of Scatophila bipiliaris Sturtevant and Wheeler is labeled “[ United States. California.] Rio Hondo[,] 3-14-50 [14 Mar 1950][handwritten]/ HOLOTYPE Scatophila bipiliaris Stvt & Whlr [pink]/6684 TYPE [dark pink; number handwritten].” The holotype is double mounted (glued to a paper point), is in good condition, and is deposited in the ANSP (6684).

Other Specimens Examined.— MEXICO. BAJA CALIFORNIA. Sierra San Pedro Mártir (La Grulla; 31°38'N, 116°26'W; 2100 m), 12 Jun 1953 , P. H. Arnaud, Jr. (4♂; USNM) .

UNITED STATES. CALIFORNIA. Fresno: Arrowhead Lake (36°49.6'N, 118°24.7'W), 24 May 1935 , A. L. Melander (1♀; USNM). Kern: Kern River (35°27.7'N, 118°46.3'W), 17Apr 1950 , A. H. Sturtevant (2♂, 4♀; USNM). Lassen: Honey Lake (40°15'N, 120°21'W), 18 Jun 1954 , A. H. Sturtevant (1♀; USNM). Los Angeles: Dark Canyon (34°08.6'N, 118°20.4'W), 16 Jul 1951 , A. H. Sturtevant (4♂; USNM); Rio Hondo (33°55.9'N, 118°10.5'W), 14 Mar 1950 , A. H. Sturtevant (10♂, 8♀; USNM); Rosemead (34°04'N, 118°05'W) 17 Mar 1950 , A. H. Sturtevant (2♂, 2♀; USNM); Saugus (16 km NE; 34°25'N, 118°32'W), 10 Apr 1953 , C. Tevan (1♀; USNM). Orange: Corona del Mar (33°35.9'N, 117°52.4'W), 19 Mar 1950 , A. H. Sturtevant (1♀; USNM). San Diego: Mt. Palomar (33°19.4'N, 116°52.7'W), 14 Jun 1948 , A. L. Melander (1♀; USNM) .

OREGON. Harney: Burns (13 km N; 43°35,2'N, 119°03.2'W), 15 Jul 1965, K. Goeden (1♀; USNM) .

UTAH. Kane: Glen Canyon (37°24'N, 110°50.6'W), Jul 1962, A. H. Sturtevant (1♀; USNM) .

Type Locality.— United States. California. Los Angeles: Rio Hondo (33°55.9'N, 118°10.5'W) .

Distribution ( Fig. 159 ).— Nearctic : Mexico (Baja California), United States (California, Oregon, Utah).

Remarks.—This species is placed in the quadriguttata group. In the original description, the type locality is listed as Montebello, not Rio Hondo. Some of the paratype labels also do not have the same locality data as listed in the original descriptio n.

Figures

FIGURE 159. Distribution map of Scatophila bipiliaris Sturtevant & Wheeler.

FIGURES 145–147. Head, thorax and wing of Scatophila. 145. Scatophila arenaria Cresson, head and thorax, dorsal view. 146–147. Wing, dorsal view. 146. S. bipiliaris Sturtevant & Wheeler. 147. S. bisignata Cresson. Scale bar = 0.2 mm.

FIGURES 149–152. Head of Scatophila bipiliaris Sturtevant & Wheeler. 149. Male, latero-oblique view. 150. Male, lateral view. 151. Female, latero-oblique view. 152. Female, lateral view. Scale bar = 0.2 mm.

FIGURES 153–155. Male terminalia of Scatophila bipiliaris Sturtevant & Wheeler. 153. Epandrium and cerci, posterior view. 154. Internal male terminalia (gonite, phallapodeme, aedeagus, neohypandrium), ventral view. 155. Same, lateral view. Scale bar = 0.1 mm.

FIGURES 156–158. Head, thorax and wing of Scatophila. 156 Scatophila bipiliaris Sturtevant & Wheeler, head and thorax, dorsal view. 157–158. Wing, dorsal view. 157. S. conifera Sturtevant & Wheeler. 158. S. cribrata (Stenhammar). Scale bar = 0.2 mm.