Subgenus Engiscaptomyza Kaneshiro, 1969

17. Mesonotum vittate.....................................................................................................................................18

- Mesonotum lacking vittae..........................................................................................................................21

18. Surstylus sharply concave, with distinct lobe at apex which forms a “C” shape; dorsal lobe of hypandrium narrowly pointed, with indistinct protrusion (see Fig. 1 in Kaneshiro, 1969). Kaua‘i ................................. ....................................................................................................... S. (Engiscaptomyza) ampliloba (Hardy)

- Surstylus less concave, straighter in profile...............................................................................................19

19. Protrusion on dorsal lobe of hypandrium somewhat short, indistinct. O‘ahu ............................................... ...................................................................................................... S. (Engiscaptomyza) inflata (Kaneshiro)

- Protrusion on dorsal lobe of hypandrium elongate, finger-like.................................................................20

20. Front femur swollen, rufous in color; scutellum with additional setulae inserted on margin between anterior and posterior scutellar setae; ovipositor blunt, with ca. 5 elongate setulae along margin. Maui, Moloka‘i ............................................................................. S. (Engiscaptomyza) crassifemur (Grimshaw)

- Front femur swollen (not as distinctly as above), entirely black in color; scutellum only bears anterior and posterior scutellar setae; ovipositor blunt, with only a single elongate setula present at apex. Maui, Moloka‘i ..................................................................................... S. (Engiscaptomyza) nasalis (Grimshaw)

21. Legs entirely yellow, except for brown apex of tarsus; leg segments short and thick. Hawai‘i .................. .......................................................................................................... S. (Engiscaptomyza) reducta (Hardy)

- Femora almost entirely brown, tinged faintly with black, narrowly yellow at bases and apices; tibia yellow with a broad brown band at apex and basal 1/3 of segment; tarsi yellow, tinged faintly with brown on apical segments. Maui .................................................................... S. (Engiscaptomyza) lonchoptera (Hardy)