Scaptodrosophila riverata species group

Diagnosis.

Body mostly yellow to yellowish brown, without patches; arista with two dorsal branches and one ventral branch in addition to the terminal bifurcation; facial carina large; prescutellar setae usually large, as long as anterior dorsocentral setae; hypandrium usually with a pair of long paramedian setae.

Description.

Male and female: Head (Figs 3, 4, 5A, B, 6A): Eyes red. Ocellar triangle yellowish brown, with 4-6 setae above ocellar setae. Frons about 1/3 width of head, largely yellowish brown to brown, with a few minute setulae medially. Fronto-orbital pale yellowish brown; anterior reclinate orbital seta usually lateral to and about 1/3 length of proclinate orbital seta; posterior reclinate orbital seta larger than other two orbital setae. Pedicel yellowish brown to brown, with a few of fine setae; first flagellomere pale yellowish. Face yellowish brown. Clypeus mostly yellow. Vibrissa prominent; subvibrissal setae small. Gena and postgena narrow, yellowish brown. Palpus yellow to yellowish brown with several setae.

Thorax (Figs 3, 4, 5C-F, 6B, C): Mesonotum yellow to yellowish brown uniformly. Postpronotal lobe yellow with 2-3 long setae, and a few of shorter setae. Acrostichal setulae in ca 8-10 regular rows. Prescutellar setae usually as long as anterior dorsocentral setae. Pleura yellow to yellowish brown uniformly. Katepisternal setae usually subequal. Wing hyaline, sometimes infuscate, lacking patch. Basal medial-cubital crossvein absent. R4+5 nearly parallel distally with M1. Halter pale yellowish. Legs mostly yellow.

Abdomen (Figs 3, 4, 5C-F, 6B, C): Tergites yellow to yellowish brown, lacking patches.

Male terminalia (Figs 7 - 12, 13A-D): Epandrium pubescent, with several setae near posterior margin and ventral corner on each side. Surstylus usually with several peg-like prensisetae on caudal margin, and several setae on outer and inner surface. Hypandrium shallow, usually with a couple of paramedian setae distally. Cercus separated from epandrium, pubescent and setigerous. Paramere developed, with few sensillae. Gonopods (as dorsal extension of the hypandrium, see Ashley and Sinclair 2017) fused with each other, broadened to hood-shaped. Aedeagus bifid, glabrous.

Female terminalia (Figs 7 - 10, 11E, 13E): Oviscapt mostly yellowish brown to brown, broadened subapically.

In the following descriptions, only those characters differing from the above description were provided.