''Crepidula ustulatulina'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of small

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a slipper snail, a marine

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Calyptraeidae The Calyptraeidae are a family of small to medium-sized marine prosobranch gastropods. MolluscaBase. Calyptraeidae Lamarck, 1809. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=141 o ...

, the slipper snails or slipper limpets, cup-and-saucer snails, and Chinese hat snails. This species occurs in the Western

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

Distribution

This recently named species is known to occur in the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

and the east coast of

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

Description

''Crepidula ustulatulina'' can be distinguished from other species of ''Crepidula'' by the following suite of characters. The shell is small (usually less than 1.5 cm), smooth, and convex. It is often cream with distinct chestnut brown spots or streaks, sometimes it is brown overall with darker spots or streaks. The internal septum is flat and white, and the animal's left side usually extends somewhat farther forward than does the right side. The margin is straight or slightly bowed. There is an oval muscle scar just anterior to the shelf on the animal's right side. The small apex is usually directly posterior and is slightly rostrate in animals living on small snails but not in those from flat substrates. The external body color is light to dark gray with opaque white or cream on the tips of the tentacles and the lips. There are usually large yellow pigment splotches on the mantle, neck and sometimes foot, visible only in life. The maximum recorded

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard ou ...

length is 13.2 mm. The shell is usually cream with brown mottling. The visible soft parts are mostly grey.

Habitat

''Crepidula ustulatulina'' is common in the low intertidal and shallow subtidal, often on dead clam shells and on columbellids and cerithids in or near sea grass. Those living on large flat substrates are oval in shape but those on small snails have highly arched and often compressed on the left side. Minimum recorded depth is 0 m. Maximum recorded depth is 1 m.

Development

The large eggs (300-340

µm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

) produce direct developing embryos with a smooth shell, and an average length of 744 µm at hatching. The large embryonic velum is not absorbed prior to hatching and the embryo hatches as a swimming pediveliger. The non-feeding larvae settle within an hour of hatching. There are between 3 and 16 eggs in each capsule and the number of eggs per capsule increases with female size.

References

* Say, T. 1822. An account of the marine shells of the United States. J. Acad. Nat. Sci. Philadelphia 2: 221-227.

External links

Info from the Smithsonian Marine Station at Fort Pierce website, a detailed report by the author of the species, R. Collin of the Smithsonian Tropical Research Institute

Malacolog info on this species
* http://stri.si.edu/sites/collinlab/tree_species/details.php?id=2 * C. ustulatulina in the Indian River Lagoon BioInventory {{Taxonbar, from=Q5184270 Calyptraeidae Gastropods described in 2002