Epigomphus, Hagen in Selys, 1854

Haber, William A., 2017, Three new species of Epigomphus (Odonata: Gomphidae) from Costa Rica, Zootaxa 4282 (1), pp. 73-94 : 92

Key to known females of Epigomphus species in Costa Rica (houghtoni, morrisoni , and wagneri are unknown)

1. Vertex with a pair of posteriorly pointing horns or tubercles arising behind lateral ocelli............................. 2

1. Vertex without postocellar horns or tubercles............................................................... 6

2. Postocellar protuberance a rounded tubercle, shorter than wide; two complete antehumeral stripes................ armatus

2. Postocellar protuberance longer than wide................................................................. 3

3. Postocellar horns broad and flat................................................................... echeverrii

3. Postocellar horns narrow and conical or acute............................................................... 4

4. Second pale antehumeral stripe reduced to a posterior spot near wing base; vertex horns conical with rounded tips................................................................................................... verticicornis

4. Second pale antehumeral stripe forming at least a partial stripe; vertex horns acute................................. 5

5. Second antehumeral stripe broken in middle; depression on rear of head shallow........................ bosquenuboso

5. Second antehumeral stripe complete; rear of head with a deep pit...................................... corniculatus

6. With two complete antehumeral stripes............................................................ subobtusus

6. Second antehumeral stripe reduced to a posterior spot......................................................... 7

7. Lateral ocellus 2 to 4 times as far from mid-dorsal line of head as from adjacent eye margin................. quadracies

7. Lateral ocellus sub-equally distant from mid-dorsal line of head as from adjacent eye margin........................ 8

8. Vertex with five shallow, longitudinal grooves behind lateral ocelli; occipital ridge with a posteriorly directed tubercle on each side....................................................................................... tumefactus

8. Vertex without five shallow, longitudinal grooves; occipital ridge without a pair of posteriorly directed tubercles.......... 9

9. Vertex with a deep groove between lateral ocelli and a groove behind each lateral ocellus; occipital ridge broadly V-shaped on posterior margin with a large dorsal hump on each side.................................................. camelus

9. Vertex without deep grooves; occipital ridge with a pair of lateral depressions............................... subsimilis