Muricidae - Hexaplex Radix

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.Merle, D., Garrigues, B. & Pointier, J.-P. (2011). ''Fossil and Recent Muricidae of the World, Part Muricinae''. 648 pp., 182 colour plates, ConchBooks, Hackenheim. . Numerous subfamilies are recognized, although experts disagree about the subfamily divisions and the definitions of 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.

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 by species. From these capsules the crawling juveniles, or more rarely planktonic larvae, hatch.

Historical value

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

The fossil record

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

Subfamilies

According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) the family Muricidae consists of these subfamilies:
* Aspellinae Keen, 1971
*Coralliophilinae Chenu, 1859 - synonym: Magilidae Thiele, 1925
*Ergalataxinae Kuroda, Habe & Oyama, 1971
*Haustrinae Tan, 2003
*Muricinae Rafinesque, 1815
*Muricopsinae Radwin & d'Attilio, 1971
*Ocenebrinae Cossmann, 1903
*Pagodulinae Barco, Schiaparelli, Houart & Oliverio, 2012
*Rapaninae Gray, 1853 - synonym: Thaididae Jousseaume, 1888
*Tripterotyphinae d'Attilio & Hertz, 1988
*Trophoninae Cossmann, 1903
*Typhinae Cossmann, 1903
;Synonyms:
*Subfamily Drupinae Wenz, 1938: synonym of Rapaninae Gray, 1853
*Genus Drupinia ic synonym of ''Drupina'' Dall, 1923
*Genus Galeropsis Hupé, 1860: synonym of '' Coralliophila'' H. Adams & A. Adams, 1853
* Tritoninae Gray, 1847: synonym of Ranellidae Gray, 1854 (Invalid: type genus placed on the Official Index by Opinion 886 unior homonym of Triton Linnaeus, 1758

Image:Babelomurex nagahorii 01.JPG, ''Babelomurex nagahorii''
Image:Bolinus cornutus 01.jpg, ''Bolinus cornutus''
Image:Chicomurex venustulus 01.JPG, ''Chicomurex venustulus''
Image:Chicoreus aculeatus 01.JPG, ''Chicoreus aculeatus''
Image:Coralliophila fearnleyi 01.JPG, '' Coralliophila fearnleyi''
Image:Drupa morum morum 01.JPG, ''Drupa morum''
Image:Drupella cornus 01.JPG, ''Drupella cornus''
Image:Hadriania trunculata 02.JPG, ''Hadriania trunculata''
Image:Haustellum haustellum 01.JPG, '' Haustellum haustellum''
Image:Hexaplex radix 01.jpg, ''Hexaplex radix''
Image:Homalocantha zamboi.JPG, ''Homalocantha zamboi''
Image:Indothais malayensis 01.JPG, ''Indothais malayensis''
Image:Lataxiena fimbriata 01.JPG, ''Lataxiena fimbriata''
Image:Latiaxis mawae 01.JPG, ''Latiaxis mawae''
Image:Morula biconica 01.JPG, ''Morula biconica''
Image:Murex pecten 001.JPG, ''Murex pecten''
Image:Nucella lapillus 01.JPG, ''Nucella lapillus''
Image:Ocenebra erinaceus fossil 01.jpg, ''Ocenebra erinacea''
Image:Orania pacifica 01.JPG, ''Orania pacifica''
Image:Phyllonotus evergladensis 01.JPG, ''Phyllonotus evergladensis''
Image:Pteropurpura festiva 01.JPG, ''Pteropurpura festiva''
Image:Rapa rapa 01.JPG, ''Rapa rapa''
Image:Rapana bezoar 01.JPG, '' Rapana bezoar''
Image:Rapana venosa 01.JPG, '' Rapana venosa''
Image:Reishia bronni 01.JPG, ''Reishia bronni''
Image:Siratus alabaster 01.jpg, ''Siratus alabaster''
Image:Spinucella tetragona 01.JPG, '' Spinucella tetragona''
Image:Stramonita haemastoma 01.JPG, '' Stramonita haemastoma''
Image:Vokesimurex gallinago gallinago 01.JPG, ''Vokesimurex gallinago''

References

*Houart, R. (1994). ''Illustrated Catalogue of Recent Species of Muricidae named since 1971''. 181 pp. ncl. 28 pls. Verlag Christa Hemmen, Wiesbaden. .
*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

CAAB listing for family Muricidae

George E.Radwin and Anthony D'Attilio: The Murex shells of the World
Stanford University press, 1976,
* Pappalardo P., Rodríguez-Serrano E. & Fernández M. (2014). "Correlated Evolution between Mode of Larval Development and Habitat in Muricid Gastropods". '' PLoS ONE'' 9(4): e94104.

Miocene Gastropods and Biostratigraphy of the Kern River Area, California; United States Geological Survey Professional Paper 642

{{Authority control

Taxa named by Constantine Samuel Rafinesque