Muricidae

Muricidae
Shell of Chicoreus palmarosae
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Caenogastropoda clade Hypsogastropoda clade Neogastropoda
Superfamily:	Muricoidea
Family:	Muricidae da Costa, 1776
Subfamilies
See text.

Muricidae, common names murex snails or rock snails, is a large and varied taxonomic family of small to large predatory sea snails. At least 1,000 species of muricids are known, and there are numerous subfamilies.

Many muricids have unusual shells which are considered attractive by shell collectors and by interior designers.

Shell description

The muricid shells are variably shaped, generally with a raised spire and strong sculpture with spiral ridges and often axial varices (tipically three or more varices on each whorl), also frequently bearing spines, tubercles or blade-like processes. Periostracum is absent in this family. The aperture is variable in shape, may be ovate to more or less contracted, with a well marked anterior siphonal canal that may be very long. The shell's outer lip is often denticulate inside, sometimes with a tooth-like process on its margin. The columella is smoothish to weakly ridged. The operculum is corneous, of variable thickness, with nucleus near the anterior end or at about midlength of outer margin.

Many muricids have episodic growth, which means that the shell grows in spurts, remaining the same size for a while (during which time the varix develops) before rapidly growing to the next size stage. The result is the series of above mentioned varices on each whorl.

A mass of muricid egg capsules in a tidepool in Central California

Life habits

Most species of muricids are carnivorous, active predators that feed on other gastropods, on bivalves, and on barnacles. The access to the soft parts of the prey is typically obtained by boring a hole through the shell by means of a softening secretion and the scraping action of the radula. Because of their carnivorous way of life, some especies may be considered pests, as they may cause considerable destruction in exploited natural beds, and also in areas of culture of commercial bivalves.

Muricids lay eggs in protective corneous capsules (of size and shape varying with species) from which the crawling juveniles, or more rarely planktonic larvae, hatch.

The fossil record

The family Muricidae first appears in the fossil record during the Aptian age of the Cretaceous period.

Subfamilies

Subfamilies within the family Muricidae are as follows:

Numerous Hexaplex trunculus for sale in a fishmarket in Spain

• Coralliophilinae Chenu, 1859
• Ergalataxinae Kuroda, Habe & Oyama, 1971
• Haustrinae Tan, 2003
• Muricinae Rafinesque, 1815
• Muricopsinae Radwin & d'Attilio, 1971
• Ocenebrinae Cossmann, 1903
• Rapaninae (=Thaidinae) Gray, 1853
• Tripterotyphinae d'Attilio & Hertz, 1988
• Trophoninae Cossmann, 1903
• Typhinae Cossmann, 1903

References

This article includes a list of references or external links, but its sources remain unclear because it has insufficient inline citations. Please help to improve this article by introducing more precise citations where appropriate. (August 2009)

• Poutiers, J. M. (1998). Gastropods in: FAO Species Identification Guide for Fishery Purposes: The living marine resources of the Western Central Pacific Volume 1. Seaweeds, corals, bivalves and gastropods. Rome: FAO. page 553.
• Rosenberg, Gary (1992) The Encyclopedia of Seashells. New York: Dorset Press.
• Vaught, K.C. (1989) A Classification of the Living Mollusca. American Malacologists, Inc., Melbourne, Florida.

External links

Wikispecies has information related to: Muricidae

Wikimedia Commons has media related to: Muricidae

• CAAB listing for family Muricidae