Crepidula ustulatulina is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of small sea snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a slipper snail, a marine gastropod mollusk in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Calyptraeidae

Calyptraeidae

Calyptraeidae, common name the slipper snails or slipper limpets, cup-and-saucer snails, and Chinese hat snails are a family of small to medium-sized marine prosobranch gastropods...

, the slipper snails or slipper limpets, cup-and-saucer snails, and Chinese hat snails.

This species occurs in the Western Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

.

Distribution

This recently-named species is known to occur in the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

 and the east coast of Florida

Florida

Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

.

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

Gastropod shell

The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...

 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 microns) produce direct developing embryos with a smooth shell, and an average length of 744 microns 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.

External links

• http://www.sms.si.edu/IRLSpec/Crepid_ustula.htmInfo 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
  Smithsonian Tropical Research Institute
  The Smithsonian Tropical Research Institute in Panama, the only bureau of the Smithsonian Institution based outside of the United States, is dedicated to understanding biological diversity. What began in 1923 as small field station on Barro Colorado Island in the Panama Canal Zone has developed...
  
  ]
• 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