A review of the deep-water hermit crab species of the genus Paragiopagurus Lemaitre, 1996 from the world oceans is presented. The core specimen base for this study has come primarily from the abundant collections of species of this genus obtained during French campaigns over the last four decades, and complemented with numerous specimens from many other deep-sea expeditions and deposited in various museum holdings around the world. Paragiopagurus is one of the most speciose genus among the Parapaguridae Smith, 1882, although it is considered a phylogenetically heterogeneous assemblage and does not appear to have an apomorphy of its own. Bathymetrically, the species range in depth from 36 to 2034 m, although they occur most frequently between 200 and 1000 m. The species utilize as housing, gastropod shells (or rarely scaphopod shells, siliceous sponges, or hollow pieces of wood) that may or may not be colonized by actinians or zoanthids. In this review, 24 species are recognized, of which five are new, P. laperousei n. sp., P. orthotenes n. sp., P. oxychelos n. sp., P. trilineatus n. sp., and P. umbonatus n. sp. The new species are fully described and illustrated. All previously known species of the genus are diagnosed or redescribed, and previously published illustrations of important taxonomic characters assembled and complemented, when useful, with new illustrations. The treatment of each species includes a full synonymy, materials examined (type and non-types), colouration, habitat or type of housing used, distribution, and remarks on taxonomy and morphological affinities. Colour photographs are included for 14 of the species. Parapagurus curvispina de Saint Laurent, 1974, a species tentatively moved after its description to Sympagurus Smith, 1883 and then to Paragiopagurus, is herein transferred with certainty to Oncopagurus Lemaitre, 1996. Parapagurus spinimanus Balss, 1911, a species that had been incorrectly placed in Paragiopagurus, is herein moved to Sympagurus. Parapagurus sculptochela Zarenkov, 1990, a taxon previously considered a junior synonym of Paragiopagurus boletifer (de Saint Laurent, 1972), is herein resurrected as a valid species of Paragiopagurus. The bathymetric and geographic distributions of Paragiopagurus species are summarized and briefly discussed, including a summary table, graph, and map with generalized distribution patterns. |
