Triacanthoneus

Key to the species of Triacanthoneus (modified from Anker, 2010)

1. Orbital margin of carapace forming acute tooth-like projection, dorsolateral teeth slightly anterior to mediodorsal tooth............................................................................ Triacanthoneus alacranes Anker, 2010

- Orbital margin of carapace without tooth-like projection, dorsolateral teeth clearly anterior to mediodorsal tooth.......... 2

2. Eyes not visible in dorsal view covered by carapace, tip of rostrum reaching midportion of third antennular article................................................... Triacanthoneus akumalensis Alvarez, Iliffe, Gonzalez & Villalobos, 2012

- Eyes visible in dorsal view, tip of rostrum reaching midportion of second antennular article.......................... 3

3. Dorsolateral teeth of carapace in a submarginal position near orbital margin; posterior margin of telson with distinct medial U- shaped notch.............................................................. Triacanthoneus chapelianus n. sp.

- Dorsolateral teeth of carapace in hepatic position; posterior margin of telson straight, without U-shaped notch............ 4

4. Major chela with fingers longer than palm, ventral tooth of rostrum directed forwards...... Triacanthones toro Anker, 2010

- Major chela with fingers shorter than palm, ventral tooth of rostrum directed downwards.................................................................................................... Triacanthoneus pacificus Anker, 2010