Common slipper shell
|Common slipper shell|
|A live but washed-up stack of Crepidula fornicata with a small chiton on the left; the lowest individual (on the right of this stack) would have been fixed to a hard surface.|
The common slipper shell, Crepidula fornicata, has many other common names including common Atlantic slippersnail, boat shell, quarterdeck shell, fornicating slipper snail, and it is known in Britain as the "common slipper limpet". This is a species of medium-sized sea snail, a marine gastropod mollusc in the family Calyptraeidae, the slipper snails and cup and saucer snails.
This sea snail has an arched, rounded shell. On the inside of the shell there is a white "deck" which causes the shell to resemble a boat or a slipper, hence the common names. Some of these may be flat, slightly arched, or arched heavily. The 'Flat slipper shell' is also another type of slipper shell.
It was introduced to the state of Washington. The species was however brought to Europe together with the eastern oyster Crassostrea virginica. In Belgium, the first slipper limpet was found on 28 September 1911 attached to an oyster in Ostend and since the 1930s, it is seen as a common species along Belgian coast.
The species is considered an invasive species in Denmark, France, Italy, the Netherlands, Spain, and the United Kingdom, and has also spread to Norway and Sweden. It is known to damage oyster fisheries. The slipper limpet has little to no predators in Europe, and can thrive on several types of hard bottoms and shellfish banks. A continued expansion to the north is probably inhibited by temperature: low temperatures during the winter can slow down or inhibit the development of the slipper limpet.
“Many different avenues can be ventured upon to find the perfect target market and the best way to market these shellfish. Slipper limpets are a versatile food. They have the flavor and individualism to stand alone as a main course, an appetizer or be incorporated into many different dishes. Before, during and after cooking slipper limpets produce a good amount of liquid which can be boiled down into broth or stock. The liquid itself could also be used as a clam juice substitute. We believe these shellfish delicacies have the potential to fill a niche in seafood market. If expressed to the public correctly, people will embrace this new shellfish and a demand for Crepidula fornicate will result in vastly increasing commercial and restaurant sales. Therefore, this shellfish and its recipes could become commercially important in the years to come. Recipes including limpets have been published in Scottish cookbooks; in Hawaii they are considered a delicacy and the Azores highly value them in their cultural dishes.” Roger Williams University's report.
Generally for Calyptraeidae, feeding habits include planktonic and minute detrital food items through either suspension or deposit feeding.
The species is a sequential hermaphrodite. The largest and oldest animals, at the base of a pile are female, the younger and smaller animals at the top are male. If the females in the stack die, the largest of the males will become a female.
This article incorpoates CC-BY-SA-3.0 text from the reference 
- 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 2011-01-13
- Welch J. J. (2010). "The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence". PLoS ONE 5(1): e8776. doi:10.1371/journal.pone.0008776.
- Global Invasive Species Database
- Joint Nature Conservation Committee
- Marine Life Information Network for Britain and Ireland
- Global Invasive Species Database
|Wikimedia Commons has media related to Crepidula fornicata.|
- Common Atlantic slipper shell:Master/Mistress of Metamorphosis
- Gould A. A. (1870). Report on the Invertebrata of Massachusetts. page 271.