Key to Pupae of Culicoides (Monoculicoides) of North America

1 Dorsal apotome without dorsomedial tubercle (Figs. 3 A–D, 4A–B), with dark banding on apex of pedicel and base of respiratory organ (Fig. 1), respiratory organ elongate, slender with black apex, midlength with scales, 2–5 subbasal pores (Figs. 2 A– B), shagreen restricted to the anterior, posterior, and lateral margins of the abdominal segments 3–7 or absent (Figs. 6 & 7), terminal process extending posterolaterally to laterally, with dark apex (Figs. 8 A–B)................ C. (Monoculicoides) (2)

- Specimens without above combination of features....................................... other species of Culicoides

2 Dorsal apotome bare of spicules (Fig. 4B)........................................................ C. grandensis

- Dorsal apotome covered in spicules (Figs. 3 A–D)............................................................ 3

3 D–5–T longer than half the length of either D–1–T or D–2–T (Fig. 5A)............................... C. shemanchuki

- D–5–T less than half the length of either D–1–T or D–2–T (Fig. 5B)............................................. 4

4 Dorsal apotome with spicules of uniform size (Fig. 4A)...................................................... 5

- Dorsal apotome with spicules of varying size, with the longest spicules on the lateral margins (Figs. 3 B–D).............. 6

5 Less than 3/4 of dorsal apotome covered in spicules (Fig. 3A); 3–4 subbasal pores on respiratory organ (Fig. 2B); CL–3–H present (Fig. 4C)........................................................................... C. occidentalis

- Almost all of the dorsal apotome covered in spicules (Fig. 4A); 1–2 subbasal pores; CL–3–H absent............. C. stigma

6 Lateral shagreen of segment 8 of the abdomen abundant (Fig. 6B); anterior 1/3 margin of abdominal segment 9 markedly swollen (Fig. 8A); CL–3–H present (as in Fig. 4C)......................................................... C. riethi

- Segment 8 of the abdomen with little to no lateral shagreen (Fig. 7); anterior margin of abdominal segment 9 at most slightly swollen (Fig. 8B); CL–3–H absent........................................................................ 7

7 L–2, L–3, and L–4 of abdominal segments 4–7 each on a long bifid tubercle with elongate and slender apices, with lateral shagreen on segments 4–7 (Fig. 7A)............................................................... C. sonorensis

- L–2, L–3, and L–4 of abdominal segments 4–7 each on a short bifid tubercle with short and blunt apices, without lateral shagreen on segments 4–7 (Fig. 7B)............................................................... C. variipennis