These recent changes in the definition of Crepidula are based on both DNA sequence data as well as anatomical work. Dissections of various calyptraeids show that species that are now placed in Grandicrepidula and Maoricrypta are anatomically very different from the true Crepidula. If only the shells are examined this difference is not apparent. This distinction is supported by DNA sequence data from 3 genes (COI, 16S and 28S).[3]
The genus Crepidula is probably the best studied group within the calyptraeids. A variety of species are commonly used in developmental, ecological, and behavioral research.[4] They have been the major focus of research on protandrous sex-change in marine invertebrates and have been used to demonstrate that sex change is environmentally mediated (the timing of sex change depends on association with other individual snails).[5][6][7]Crepidula fornicata and Crepidula onyx are well-studied examples of invasive, exotic species in marine habitats.[8][9]
Due to their simple shells and plastic morphology, calyptraeid taxonomy is challenging. In many cases distinct species with similar-looking shells have been lumped into a single species with either global or unusual distributions. In these cases close examination of the mode of development or of DNA data is vital to verify the species identity. Because such taxonomic lumping is difficult to clear from the internet or from the literature many species range estimates available on the internet include dubious data or data from species that have been taken out of synonymy.
Species
Species within the genus Crepidula include:[10][11][12]
Crepidula youngi (Powell, 1940): synonym of Maoricrypta youngi Powell, 1940
Species that were previously placed in the genus Crepidula but have subsequently been removed from the genus on the basis of work by Bruce Marshall of the Te Papa Museum and Rachel Collin of the Smithsonian Institution include the following:
Now Maoricrypta:
Crepidula costata is a synonym for Maoricrypta costata - ribbed slipper shell
Like all calyptraeids, slipper snails are sedentary filter-feeders. Adults use their large gill to capture microalgae from suspension, but there is some evidence that small juveniles can also use the radula to scrape algae from the substrate.
Introduced and invasive Crepidula species
Crepidula fornicata - Native to the east coast of North America and ranging from Florida north into Canada. This species is now widespread and considered highly invasive along the north coast of Spain and France, along much of England's coastline and into the North Sea. It has also been reported from San Francisco Bay, Puget Sound and the Mediterranean Sea.
Crepidula convexa - Native to the east coast of North America and ranging from South Carolina to New England. This species has been reported from Puget Sound and San Francisco Bay.
^Collin, Rachel. 2003. The Utility of Morphological Characters in Gastropod Phylogenetics: An Example From the Calyptraeidae. Biological Journal of the Linnean Society, 4: 541–593
^Henry, Jonathan J.; Collin, Rachel; Perry, Kimberly J.. 2010. The Slipper Snail, Crepidula: An emerging Lophotrochozoan model system. Biological Bulletin, 218(3): 211-229.
^Mérot, Claire; Collin, Rachel. 2012. Effects of food availability on sex change in two species of Crepidula (Gastropoda: Calyptraeidae). Marine Ecology Progress Series, 449: 173-181.
^Collin, Rachel; McLellan, Michelle; Gruber, Karl F.; Bailey-Jourdain, Catherine. 2005. Effects of Conspecific Associations on Size at Sex Change in Three Species of Calyptraeid Gastropods. Marine Ecology Progress Series, 1: 89-97.
^Collin, Rachel. 1995. Sex, size, and position: a test of models predicting size at sex change in the protandrous gastropod crepidula fornicata. The American Naturalist, 146(6): 815-831.
^Coe, Wesley R. 1948. Nutrition and sexuality in protandric gastropods of the genus Crepidula. Biol. Bul. 94(3): 158-160.
^Hendler, G. and D. R. Franz. 1971. Population dynamics and life history of Crepidula convexa Say (Gastropoda: Prosobranchia) in Delaware Bay. Biol. Bul. 141: 514-526.
^Ross, Landon T. (1965). "The genus Crepidula in North America: its taxonomy, phylogeny, and distribution. unpublished Florida State Univ. thesis". Retrieved on May 2009.[2]
^Rosenberg, G. (2010). Crepidula aeola Dall, 1927. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532681 on 2011-01-11
^ abRosenberg, G. (2010). Crepidula aplysioides Reeve, 1859. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532682 on 2011-01-11
^Rosenberg, G. (2010). Crepidula argentina Simone, Pastorino & Penchaszadeh, 2000. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532683 on 2011-01-11
^Rosenberg, G. (2010). Crepidula cymbaeformis Conrad, 1844. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532684 on 2011-01-11
^Gofas, S. (2010). Crepidula fornicata (Linnaeus, 1758). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138963 on 2011-01-11
^Gofas, S. (2010). Crepidula moulinsii Michaud, 1829. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=180993 on 2011-01-12
^Rosenberg, G. (2010). Crepidula navicula (Mörch, 1877). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532685 on 2011-01-12
^Gofas, S. (2010). Crepidula porcellana (Linnaeus, 1758). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138965 on 2011-01-12
^Rosenberg, G. (2010). Crepidula protea (d'Orbigny, 1841). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532686 on 2011-01-12
^Gofas, S. (2010). Crepidula unguiformis Lamarck, 1822. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138966 on 2011-01-12
^Gofas, S. (2010). Crepidula gibbosa Defrance, 1818. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138964 on 2011-01-12
Collin, R. 2003. The Utility of Morphological Characters in Gastropod Phylogenetics: An Example From the Calyptraeidae. Biological Journal of the Linnean Society, 4: 541–593
Collin, R. 2003. Phylogenetic Relationships Among Calyptraeid Gastropods and Their Implications for the Biogeography of Marine Speciation. Systematic Biology, 5: 618–640.
Collin, R. 2002. Another Last Word on Crepidula Convexa With a Description of C. Ustulatulina N. Sp. (Gastropoda: Calyptraeidae) From the Gulf of Mexico and Southern Florida. Bulletin of Marine Science, 1: 177–184.
Collin, R. 2000. Phylogeny of the Crepidula plana (Gastropoda: Calyptraeidae) cryptic species complex in North America. Canadian Journal of Zoology. 78: 1500–1514.
Hoagland, K.E. 1977. Systematic review of fossil and recent Crepidula and discussion of the evolution of the Calyptraeidae. Malacologia 16(2): 353-420
Vaught, K.C. (1989). A classification of the living Mollusca. American Malacologists: Melbourne, FL (USA). ISBN0-915826-22-4. XII, 195 pp. (
Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 180–213