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
Rafinesque, 1815
Subfamilies

See text

Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With about 1,600 living species, the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognized.[1] Numerous subfamilies are recognized, although experts disagree about the subfamily divisions and about defining the genera. Many muricids have unusual shells which are considered attractive by shell collectors and by interior designers.

Shell description

Muricid shells are variably shaped, generally with a raised spire and strong sculpture with spiral ridges and often axial varices (typically 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; it 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 denticulated inside, sometimes with a tooth-like process on its margin. The columella is smoothish to weakly ridged. The operculum is corneous and of variable thickness, with the nucleus near the anterior end or at about midlength of the outer margin.

Many muricids have episodic growth, which means their shells grow 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, bivalves, and 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 carnivory, some species may be considered pests because they can cause considerable destruction both in exploited natural beds of bivalves, and in farmed areas of commercial bivalves.

Muricids lay eggs in protective, corneous capsules the size and shape of which vary with the species. From these capsules the crawling juveniles, or more rarely planktonic larvae, hatch.

Historical value

Members of the genus were harvested by early Mediterranean peoples, with the Phoenicians possibly the first to do so, to extract an expensive, vivid, and stable dye known as imperial, royal or Tyrian purple.

The fossil record

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

Subfamilies

Numerous Hexaplex trunculus for sale in a fishmarket in Spain

According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) the family Muricidae consists of these subfamilies:

Synonyms

References

  1. Merle, D., Garrigues, B. & Pointier, J.-P. (2011). Fossil and Recent Muricidae of the World, Part Muricinae. 648 pp., 182 colour plates, ConchBooks, Hackenheim. ISBN 978-3-939767-32-9.

External links

Wikispecies has information related to: Muricidae
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