Prionocidaris verticillata OR Plococidaris verticillata?
Strictly nocturnal. Primary spines stout and bearing three or four whorls; the shaft in between the whorls is ornamented in dense granules, not aligned. Source: http://www.nhm.ac.uk/research-curation/r...
Not sure which scientific name applies. World Register of Marine Species (WoRMS) has moved this to Plococidaris (http://www.marinespecies.org/aphia.php?p...) while most websites still use Prionocidaris. Spotted at Dive and Trek House Reef during a night dive. Depth of 8m.