Key to females of species of Culicoides (Marksomyia)

1. Spermathecae totally desclerotised (fig 38).............................................................. dycei

- Spermathecae partially sclerotised (fig 33–37)............................................................... 2

2. Spermathecae partially or almost completely sclerotised, rounded (fig 33–34)..................................... 3

- Spermathecae pear shaped, with only necks sclerotised (fig 35–37)............................................. 4

3. Wings with two pale spots in cell M4 (fig 25, 26)....................................................... marksi

- Wings with one pale spot in cell M4 (fig 27).................................................. pseudostigmaticus

4. On antennae, SCo absent from basal antennomeres 4–10.......................................... parvimaculatus

- On antennae, SCo present on at least 9 or 10................................................................ 5

5. On antennae, SCo distribution 3(4–9)11–15; 15 with two or three SCh........................................ zentae

- On antennae, SCo distribution 3(8,9)10–15; 15 with at least five SCh.......................................... kayi