dcsimg

Comprehensive Description

provided by Smithsonian Contributions to Zoology
Scatella (Neoscatella) victoria (Cresson)

Neoscatella victoria Cresson, 1935:360.

DIAGNOSIS.—Specimens of this species are similar to those of S. vittithorax and S. insularis but may be distinguished from them and other congeners by the following combination of character states (male unknown): mesofrons more sparsely pollinose than parafrons or fronto-orbits, particularly laterad of ocellar triangle, appearing subshiny to shiny; lateroclinate fronto-orbital bristles subequal in length; dorsum of interfoveal carina narrowly developed; distance between antennal bases about equal to length of third antennal segment; facial coloration grayish yellow to brown, slightly darker dorsally around interfoveal hump; marginal facial setae distinctly larger than those along median surface, with 2–3 pairs of larger, slightly dorsally curved setae aligned between interfoveal carina and posteroventral corner of face; orientation of eye at very slight oblique angle to plane of oral margin; scutum and scutellum more or less concolorous, brown but with 2 grayish stripes anteriorly along acrostichal track extending posteriorly no more than half length of scutum; scutum lacking distinct median stripe; setae of front coxa and femur undifferentiated; tarsi dark brown, nearly concolorous colorous with femora and tibiae; female wing uniformly infuscated, brown, except for white areas; cell R3 with 2 distinct white areas, basal one narrowed medially, expanding basally to subequal length, apical spot not reaching vein R2+3; discal cell with 1 subbasal white spot; cell R5 with 4 subequal white spots, one basad of level of posterior crossvein, 2 aligned and apicad of posterior crossvein, same distance as basal spot, apical spot centered in membrane; discal cell with 1 posterodistal spot; cell M2 with 3 spots, 2 aligned basally, apical one appressed against vein M1+2; cell M4 with 1 white spot more or less aligned with basal spot in cell R5.

DESCRIPTION (based on female holotype).—A moderately small shore fly, length 2.34 mm; mostly brown, but with some grayish or grayish brown areas; pollinose to sparsely pollinose, some areas shiny.

Head: Head width-to-height ratio 1 : 0.64 frons pollinose laterally becoming bare around ocellar triangle, latter area shiny with metallic luster; mesofrons separated from parafrons by membranous appearing, dull greenish charcoalish gray wedge extending posteriorly from anterior margin; ocellar triangle distinctly pollinose, brown; lateroclinate fronto-orbital bristles subequal in length. Antenna with first and second segments mostly blackish; third segment brownish black, paler basally, slightly yellowish, more pubescent; length of third segment subequal or longer than combined length of first and second segments; arista appearing bare, with short, sparse, mostly inconspicuous setae; distance between antennal bases short, less than length of third segment. Face with distinct interfoveal carina and lacking dorsomedian short sulcus; facial setae conspicuous, especially those along margins; with 3–4 longer porrect to slightly upcurved setae aligned between interfoveal carina and posteroventral angle of face; face mostly yellowish brown, slightly darker dorsally and posterolaterally. Eye nearly round, eye width-to-height ratio 1 : 1.1. Gena moderately low, eye-to-cheek ratio 1 : 0.20; genal coloration lighter than face, more grayish to faintly bluish gray, becoming darker posteriorly. Clypeus generally concealed.

Thorax: Mostly brown, becoming more conspicuously brown on scutellum; extreme anterior margin grayer, gray coloration extending into humeral callus. Pleural areas brown to yellowish brown dorsally, becoming grayer posteriorly and ventrally. Legs concolorous, femora gray to blackish brown, becoming darker apically; tibiae mostly blackish; tarsi blackish. Wing (Figure 45) as described in diagnosis.

Abdomen: Terga bicolored, anterior margins brownish, brownish coloration becoming wider laterally; posterior margin mostly gray to faintly bluish gray.

TYPE MATERIAL.—Female holotype is labeled: “Victoria 1888 [hand-written]/[yellow]/TYPE No. Neoscatella VICTORIA 6514 E T Cresson, Jr. [red].” The holotype and 1 female paratopotype are in the Academy of Natural Sciences of Philadelphia, type number 6514. The holotype is double mounted (minute nadel in dark base) and is in fair condition. The left wing is missing, and the right one is slightly tattered.

GEOGRAPHIC DISTRIBUTION (Figure 40).—Known only from the type-locality, “Victoria” (probably near Melbourne).
license
cc-by-nc-sa-3.0
bibliographic citation
Mathis, Wayne Neilsen and Wirth, W. W. 1981. "Studies of Ephydrinae (Diptera: Ephydridae), IV: Revision of the Australian Species of Subgenus Neoscatella Malloch." Smithsonian Contributions to Zoology. 1-27. https://doi.org/10.5479/si.00810282.325