Scaptomyza aberrans Hardy 1965

Body: 2.2mm; wings: 2.5mm

This species fits near S. fuscifrons Hackman but is differentiated by the very different development of the male genitalia; by having the ninth tergum comparatively broad, longer than the anal plates, and lobate on the posteroventral margins. The parameres are parallel to the aedeagus and the aedeagus is slender and sharp-pointed. The median lobes which are developed on the ninth sternum of fuscifrons and most of the other species of Alloscaptomyza are apparently lacking.

HAWAIIAN ISLANDS: Molokai and Lanai

Brown, tinged with yellow on the bases of the terga. The anal plates are about as high as long. The ninth tergum is rather broad, longer than the anal plates, and distinctly lobate on each posteroventral margin. The claspers are simple but readily visible from a lateral view. The parameres are parallel to the aedeagus; the latter is slender, sharp-pointed. The median lobes of the ninth sternum, which are characteristic of most species of Alloscaptomyza, are not discernible in this species and are evidently rudimentary.

Fitting the description of the male except for sexual characters.

Head. About 1/3 higher than long, tapered ventrally as seen in direct lateral view. At the broadest point the width of the gena is about 1/4 the eye height. Front entirely opaque black; gray on the orbits and on the ocellar triangle. The occiput is dark brown to black on the upper 4/5, covered with gray pollen; the extreme lower portion is tinged with brown. The fact is black except for a ting to yellow on the upper portion. The clypeus is dark brown to black. The palpi are yellow; each has one small black apical bristle plus several black setae near the apex. One moderately strong bristle is present on the upper edit of the vibrissal row; this is almost equal in size to the upper reclinate bristles of the front. The face is distinctly carinate. The anterior reclinate bristles are about 1/2 as long as the proclinates and are situated opposite the latter. The first two antennal segments are yellow, tinged slightly with brown on the dorsal portions; the third segment is dark brown. The arista has 3 or 4 dorsal and 1 ventral ray in addition to the rather small apical fork. Thorax. Brown to black, tinged faintly with rufous in the ground color of the pleura, and covered with gray pollen except for a faint indication o a median brown vitta which extends from the posterior margin of the mesonotum 1/2 the distance between the 2 pairs of dorsocentral bristles. Four rows of acrostichal setae are present on the mesonotum. The anterior dorsocentrals are situated slightly in front of the line drawn between the first suraalars. The humeral bristle is about equal to the posterior notopleural bristle. The anterior sternopleural bristle is about 1/2 as long as the posterior bristle.\ Legs. Yellow except for a tinge of brown on the apices of the tarsi. The front tibiae and tarsi are rather densely covered with short erect setae. The front basitarsus is about 1/3 as long as the tibia.

This species is in the subgenus Alloscaptomyza.

Subhyaline. The third costal section is 3.6 times longer than the fourth and the costal fringe extends 2/3 to 3/4 the distance between the apices of veins R2+3 and R4+5. The last section of vein M1+2 is 1/6 times longer than the penultimate section. The last section of vein M2+4 is 1/2 to 2/3 longer than the m crossvein.