Notiphila robusta Mathis 1979

Notiphila (Notiphila) robusta

DIAGNOSIS.—This species belongs to the avia group wherein it is closely allied to N. avia. Externally, the differences between specimens of N. robusta and those of N. avia are slight and reference to characters of the male genitalia will usually be necessary to distinguish one from the other. Except for a very thin basal edge of light coloration, the third antennal segment is almost entirely dark. Many specimens of N. avia have darkened third antennal segments, especially in the West, but this is not the usual character state for specimens from near the type-locality of N. robusta. Several structures of the male genitalia are diagnostic. The shape of the ventral epandrial process, hypandrial process, and basiphallus is characteristic of this species. See Figures 52–54.

DESCRIPTION.—Moderately large shore flies based on the length of the thorax; with grayish tan coloration and few contrasting, darker areas.

Head: Head ratio 1:0.74; postfrons ratio 1:0.63; frons mostly unicolorous, brown with some gray pollinosity, except for lighter brown median triangular areas surrounding ocellar triangle; paravertical bristle subequal with genal bristle. Antennal segments mostly dark brown to black, base of third segment with narrow margin of contrasting lightened area; arista with 8 dorsal branches. Face lighter than frons, yellow; prefrons ratio 1:0.89; facial setae strong, subequal to genal bristle, numbering 2–3. Eye ratio 1:0.74; eye-to-cheek ratio 1:0.25; gena moderately wide, uniformly unicolorous, slightly grayer than face, genal bristle distinct but not more strongly developed than facial setae. Maxillary palpus pale, yellow.

Thorax: Coloration grayish brown with some faint tinges of darker coloration, generally immaculate; pleural areas not distinctly contrasting in color with mesonotum, immaculate. Femora dark, dusted gray, pale apically; tibiae dark except at apices; front tarsomeres dark, concolorous with front tibia; middle and hind tarsi appearing somewhat dark on anterior surface, otherwise with considerable pallor. Setal fascicle of hind basitarsus dark, black. Wing ratio 1:0.36; costal vein ratio 1:0.33; M1+2 vein ratio 1:0.71.

Abdomen: —Generally concolorous with thorax but with some darkened areas dorsally although these are not distinct, blending marginally. The abdomen was removed before measurements were taken. Male genitalia as in diagnosis and Figures 52–54.

TYPE-MATERIAL.—Holotype male: “Mi 61 Rte. 58 La Verendrye Prov(incial). P(ar)k. Que(bec). 26 VI 1965, D. M. Wood/HOLOTYPE Notiphila robusta Mathis (red).” The holotype will be deposited with the Canadian National Collection, Ottawa, type number 13774.

ETYMOLOGY.—The epithet is the Latin adjective robusta (“strong” or “robust”) referring to the large size of this species.

SPECIMENS EXAMINED.—This species is known only from the male holotype.

GEOGRAPHIC DISTRIBUTION.—The type-locality is the only site where this species has been collected.

The loewi Group

SPECIES INCLUDED.—Notiphila carinata Loew; N. cressoni, new name; N. eleomyia, new species; N. floridensis Cresson; N. latigena, new species; N. loewi Cresson; N. oriens, new species; N. pauroura, new species; N. poliosoma, new species; N. shewelli, new species; N. solita Walker; N. unicolor Loew.

DIAGNOSIS.—The hypandrial process is short, narrow, and usually bears 2–3 apical setae; the facial setae are weakly developed.

GEOGRAPHIC DISTRIBUTION.—All described species of this group occur in eastern North America, mostly east of the Mississippi River.