Pteropagurus and Catapagurus (Decapoda, Anomura, Paguridae): resource sharing or "any port in a storm"?

Additional materials of two species of the recently described pagurid genus Pteropagurus McLaughlin & Rahayu, 2006 have required an emendation of the genus. These have also provided the information needed to supplement the original species descriptions, including the unusual morphology of the male of P. spina McLaughlin & Rahayu, 2006 and the sexual dimorphism and variability found in P. spinulocarpus McLaughlin, 2007. Brief data on the larval development in Pteropagurus have been gleaned from zoeae prematurely hatched from one female of P. spinulocarpus. What heretofore had been considered a unique habitat for species of this genus, i.e. empty shells of a pelagic pteropod, was found to also provide carcinoecia for Catapagurus spinicarpus de Saint Laurent & McLaughlin, 2000, a species previously known only from its female holotype collected in the Kermadec Islands of New Zealand. The male of this species is described and species’ variability and dimorphic attributes are assessed. Consideration is given to the question of habitat choice and the morphological adaptations required for use of the unusual carcinoecia.