Scatophila adamsi Cresson

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 : 29-32

5. Scatophila adamsi Cresson

Figs. 32. 38–45 , 48

Scatophila adamsi Cresson 1935: 369 .— Sturtevant and Wheeler 1954: 186–187 [review].— Deonier 1964: 110 [key; Iowa]; 1965: 498 [natural history].— Wirth 1965: 758 [ Nearctic catalog].— Zatwarnicki 1987: 291 [checklist].— Zatwarnicki and Mathis 1994: 362 [phylogeny, mesogramma group].— Mathis and Zatwarnicki 1995: 281 [world catalog].

Diagnosis.—This species is distinguished from congeners, especially S. ordinaria , by the following combination of characters: Body with tan to brown and usually with some lighter markings, scutellar disc with partially to mostly dark but often with basal and sometimes with apical areas gray; minute shore flies, body length 1.55–1.90 mm.

Head ( Figs. 38–41 ): Lateroclinate fronto-orbital seta not so far forward, distance between lateroclinate fronto-orbital seta and medial vertical seta only slightly longer than between inner and lateral vertical setae. Lower facial seta not oriented laterally or slightly curved dorsally; ventral margin of face of ♂ distinctly emarginate, bearing laterally a cluster of long setulae and setae on each side. Genal height less than height of basal flagellomere; gena-to-eye ratio 0.23–0.26.

Thorax ( Figs. 32 , 45 ): Mesonotum ( Fig. 45 ) mostly gray with some brownish stripes; acrostichal setae small and of uniform size, arranged in 2 regular rows; dorsocentral setae 2, anterior seta sutural or just postsutural. Wing ( Fig. 32 ) moderately dark with evident pattern or pale spots; cell r 1 lacking white spots; large, quadrate white spot of cell r 3 lacking a dark center; costal vein ratio 0.24–0.27; M 1 vein ratio 0.63–0.65. Midfemur of ♂ lacking row of spine-like setae; tarsi yellowish.

Abdomen ( Figs. 42–44 ): Tergites brown to black, rather heavily microtomentose, rarely subshiny. Male terminalia ( Figs. 42–44 ): Epandrium in posterior view ( Fig. 42 ) generally oval except for truncate and conspicuously narrowed ventral margin, epandrial width nearly 0.75 height, lateral margins evenly and shallowly curved, width of ventral margin about equal to width of cercal opening; dorsal epandrial margin in posterior view ( Fig. 42 ) broadly rounded; epandrial setae about equal in length, sparser medially, more abundant along ventral margin; height of cercal opening about 1/3 epandrial height; cerci in posterior view ( Fig. 42 ) broadly lunate; aedeagus in lateral view ( Fig. 44 ) broadly rounded basally, becoming narrower posteriorly, posterior apex shallowly and angularly rounded, dorsal margin strongly excavated, cavity twice as long as wide, in ventral view ( Fig. 43 ) oval; ventral aedeagal process sinuous; phallapodeme in lateral view ( Fig. 44 ) elongate, shallowly arcuate to shallowly elbowed, dorsal portion (toward base of aedeagus) wider, with 2 shallow, rounded bumps, ventral portion more parallel sided, then tapered to point, in ventral view ( Fig. 43 ) T-shaped, width of basal crossbar about half length of medial process; postgonite in lateral view ( Fig. 44 ) V-shaped, with dorsal, wider extension somewhat rectangular, bearing setulae, ventral extension elongate, shallowly sinuous, narrow, slightly tapered, in ventral view ( Fig. 43 ) with posterior extensions narrowly clavate; neohypandrium in lateral view ( Fig. 44 ) narrowly elongated, mostly linear, very shallowly undulated, becoming slightly wider posteriorly.

Type Material.— The holotype male of Scatophila adamsi Cresson is labeled “[ United States.] Atherton, M [iss]o[uri]./ June / TYPE No. 6521[,] Scatophila ADAMSI E.T.Cresson,Jr. [pink; species name and number handwritten]. The holotype is double mounted (minute nadel in rectangular card block), is in fair condition, and is deposited in the ANSP (6521).

Other Specimens Examined.— MEXICO. BAJA CALIFORNIA. Sierra San Pedro Mártir (31°02.7'N, 115°28'W), 7 Mar 1963 , P. H. Arnaud, Jr. (1♂; USNM) .

UNITED STATES. ARKANSAS. Garland: Hot Springs (24 km W; 34°29.8'N, 93°04'W), 14–19 May 1979 , K. A. Spencer, G. C. Steyskal (1♂, 1♀; USNM) .

IOWA. Boone: Fraser (1.2 km SW; 42°07.7'N, 93°59'W), 4 Jul 1960, D. L. Deonier (1♂; USNM) ; Fraser Dam (42°07.5'N, 93°58.4'W), 4 Jul 1960, D. L. Deonier (1♂; USNM) . Warren: Banner Mine area (41°26.4'N, 93°33.8'W), 7 Aug 1960, D. L. Deonier (1♂; USNM) .

KANSAS. Riley: Manhattan (39°11'N, 96°34.3'W), 8 Jun 1932, C. W. Sabrosky (1♀; USNM) .

MARYLAND. Calvert: Chesapeake Beach (38°41.2'N, 76°32.1'W), 5 Jul 1924, J. R . Malloch (1♀; USNM) .

NEBRASKA. Antelope: Oakdale (42°04.1'N, 97°58'W), 21 Aug 1950 (1♀; USNM) .

TEXAS. Travis: Austin (30°16'N, 97°44.6'W), 16 Apr–19 Nov 1953, 1959, M. R . Wheeler (2♂; USNM); Austin (40 km N; 31°N, 97°44.6'W), 22 Sep 1951 (2♂, 1♀; USNM) .

Type Locality.— United States. Missouri. Jackson: Atherton (39°11.2'N, 94°18.3'W) .

Distribution ( Fig. 48 ).— Nearctic : Mexico (Baja California). United States (Arkansas, Iowa, Kansas, Maryland, Missouri, Nebraska, Texas).

Natural History.— Deonier (1965) reported this species from mud shores, freshet seeps, and spoil banks Specimen were rare in these habitats.

Remarks.—This species is placed in the mesogramma group.

Figures

FIGURE 48. Distribution map of Scatophila adamsi Cresson (circles), and S. hesperia Sturtevant & Wheeler (squares).

FIGURES 31–33. Head, thorax and wing of Scatophila. 31. S. variabilis Cresson, head and thorax, dorsal view. 32–33. Wing, dorsal view. 32. S. adamsi Cresson. 33. S. hesperia Sturtevant & Wheeler. Scale bar = 0.2 mm.

FIGURES 34–36. Male terminalia of Scatophila variabilis Cresson. 34. Epandrium and cerci, posterior view. 35. Internal male terminalia (gonite, phallapodeme, aedeagus, neohypandrium), ventral view. 36. Same, lateral view. Scale bar = 0.1 mm.

FIGURE 37. Distribution map of Scatophila variabilis Cresson.

FIGURES 38–41. Head of Scatophila adamsi Cresson. 38. Male, latero-oblique view. 39. male, lateral view. 40. Female, laterooblique view. 41. Female, lateral view. Scale bar = 0.2 mm.

FIGURES 42–44. Male terminalia of Scatophila adamsi Cresson. 42. Epandrium and cerci, posterior view. 43. Internal male terminalia (gonite, phallapodeme, aedeagus, neohypandrium), ventral view. 44. Same, lateral view. Scale bar = 0.1 mm.

FIGURES 45–47. Head, thorax and wing of Scatophila. 45. S. adamsi Cresson, head and thorax, dorsal view. 46–47. Wing, dorsal view. 46. S. iowana Wheeler. 47. S. mesogramma (Loew). Scale bar = 0.2 mm.