WESTERN ATLANTIC SPECIES OF THE PARAPAGURUS PILOSIMANUS COMPLEX (ANOMURA: PAGUROIDEA: PARAPAGURIDAE): DESCRIPTION OF A NEW SPECIES AND MORPHOLOGICAL VARIATIONS

Abstract

A review of the deep-water hermit crabs of the genus Parapagurus has shown that 10 of the taxa assigned to this genus, and an additional new species, represent a group of closely related species defined herein as the P. pilosimanus complex. Four species of the complex occur in the western Atlantic: P. pilosimanus, P. nudus, P. scaber, and P. alaminos, new species. These species are diagnosed or described and morphological variations evaluated and illustrated. Results of this study provide an indication of the range of variations that could be expected in species of the complex in general. Diagnostic characters at the specific level have been found in the branchiostegite, antennal acicle, left cheliped, propodal rasp of the fourth pereiopod, uropods, and telson. SEM micrographs of the scales constituting the propodal rasp are included. The right cheliped is shown to be affected by size and sexual dimorphism, and is not useful in distinguishing the species.