Note: in the key we omit two species of Cuban hystrignathids formerly placed in Hystrignathus, which will be published in the future as new combinations.
1. First cephalic annule markedly inflated; spines ending at level of procorpus... .......................................................... H. splendidus Morffe & García, sp. n.
– First cephalic annule not markedly inflated; spines surpassing the end of pro- corpus..................................... H. rosario García, Ventosa & Morffe, 2009