Discovery of a new micro-pagurid fauna (Crustacea: Decapoda: Paguridae) in the Lesser Antilles, Caribbean Sea

Six new monotypic genera and eight new species of hermit crabs of the family Paguridae Latreille, 1802 are fully described based on specimens obtained during two separate, intensive biodiversity studies on the islands of Guadeloupe, Curaçao, and Dominica in the Lesser Antilles, Caribbean Sea. The study in Guadeloupe utilized a broad variety of sampling techniques, including dredging, baited traps, and a SCUBA-operated vacuum device; in Curaçao and Dominica, a manned submersible was used. The high number of new taxa discovered is surprising given they were obtained in a relatively small area of the Antilles in habitats ranging in depth from shallow water (c. 1 m) to deep reefs (250 m). Tissue samples were extracted from most specimens for CO1 barcoding and other genetic analyses for future phylogenetic investigations. Gene sequences are reported to complement the morphological descriptions. The new species are unusual in their minute sizes, ranging 0.4-1.5 mm in shield length; and aspects of their morphology, in particular gill number and characteristics of male sexual tubes, which could not be clearly matched to any of the existing genera of Paguridae. The term “micro-pagurid” is introduced for this diverse, diminutive fauna of Paguridae (adult shield length ≤ 1.5 mm), discovered living in cryptic habitats and complex deep reef structures of these three islands. A brief, preliminary discussion of the possible significance of this micro-pagurid diversity, specialized morphology, and biogeography is included.