Muricidae
Encyclopedia
Muricidae, common name
murex snails or rock snails, is a large and varied taxonomic family
of small to large predatory sea snail
s. With approximately 1,600 living species
the Muricidae represent almost 10% of the Neogastropoda
. Additionally, 1,200 fossil species have been recognised (Merle et al. 2011). There are numerous subfamilies, although experts disagree about the subfamily divisions.
Many muricids have unusual shells which are considered attractive by shell
collectors and by interior designers.
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, 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 the nucleus near the anterior end or at about midlength of the 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
.
s. 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 species may be considered pests because they can cause considerable destruction both in exploited natural beds of bivalves, and also in farmed areas of commercial bivalves.
Muricids lay eggs in protective corneous capsules the size and shape of which vary with the species. Out of these capsules the crawling juveniles, or more rarely planktonic larvae, hatch.
age of the Cretaceous period
.
According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005)
the family Muricidae consists of these subfamilies:
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
murex snails or rock snails, is a large and varied taxonomic 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...
of small to large predatory sea snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s. With approximately 1,600 living 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...
the Muricidae represent almost 10% of the Neogastropoda
Neogastropoda
Neogastropoda is an unranked taxonomic clade of sea snails, marine gastropod mollusks. For many years prior to 2005 Neogastropoda was an order.- Description :...
. Additionally, 1,200 fossil species have been recognised (Merle et al. 2011). There are numerous subfamilies, although experts disagree about the subfamily divisions.
Many muricids have unusual shells which are considered attractive by shell
Seashell
A seashell or sea shell, also known simply as a shell, is a hard, protective outer layer created by an animal that lives in the sea. The shell is part of the body of the animal. Empty seashells are often found washed up on beaches by beachcombers...
collectors and by interior designers.
Shell description
Muricid shells are variably shaped, generally with a raised spireSpire
A spire is a tapering conical or pyramidal structure on the top of a building, particularly a church tower. Etymologically, the word is derived from the Old English word spir, meaning a sprout, shoot, or stalk of grass....
and strong sculpture with spiral ridges and often axial varices
Varix (mollusc)
A varix is an anatomical feature of the shell of certain sea snails, marine gastropod molluscs.It is a thickened axial ridge in the shell of some families of gastropods. A varix is located at intervals around the whorl, and is formed by considerable thickening of the outer lip at a resting stage...
(typically three or more varices on each whorl
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
), also frequently bearing spines, tubercles or blade-like processes. Periostracum
Periostracum
The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...
is absent in this family. The aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
is variable in shape, may be ovate to more or less contracted, with a well marked anterior siphonal canal
Siphonal canal
Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is drawn into the mantle cavity and over the gill and which serves as a chemoreceptor to locate food. In many carnivorous snails, where the siphon is particularly long, the structure...
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
Columella
Lucius Junius Moderatus Columella is the most important writer on agriculture of the Roman empire. Little is known of his life. He was probably born in Gades , possibly of Roman parents. After a career in the army , he took up farming...
is smoothish to weakly ridged. The operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
is corneous, 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 that the shell grows in spurts, remaining the same size for a while (during which time the varix
Varix (mollusc)
A varix is an anatomical feature of the shell of certain sea snails, marine gastropod molluscs.It is a thickened axial ridge in the shell of some families of gastropods. A varix is located at intervals around the whorl, and is formed by considerable thickening of the outer lip at a resting stage...
develops) before rapidly growing to the next size stage. The result is the series of above mentioned varices on each whorl
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
.
Life habits
Most species of muricids are carnivorous, active predators that feed on other gastropods, on bivalves, and on barnacleBarnacle
A barnacle is a type of arthropod belonging to infraclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile suspension feeders, and have...
s. 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 species may be considered pests because they can cause considerable destruction both in exploited natural beds of bivalves, and also in farmed areas of commercial bivalves.
Muricids lay eggs in protective corneous capsules the size and shape of which vary with the species. Out of 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, in order 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 AptianAptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
age of the Cretaceous period
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
.
Subfamilies
Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)
The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...
the family Muricidae consists of these subfamilies:
- CoralliophilinaeCoralliophilinaeCoralliophilinae is a taxonomic group, a subfamily of about 200–250 sea snails, marine gastropod mollusks commonly known as the coral snails or coral shells...
Chenu, 1859 - synonym: Magilidae Thiele, 1925 - ErgalataxinaeErgalataxinaeErgalataxinae is a taxonomic subfamily of small to medium-sized predatory sea snails, marine gastropod mollusks within the family Muricidae, the rock snails.In this subfamily, the aragonitic shell has 0–2varices.-Genera:...
Kuroda, Habe & Oyama, 1971 - HaustrinaeHaustrinaeHaustrinae is a taxonomic subfamily of predatory sea snails, marine gastropod mollusks in the family Muricidae, the murex shells or rock shells.The genera in this family were previously grouped in a larger subfamily, the Ocenebrinae.-Genera:...
Tan, 2003 - MuricinaeMuricinaeMuricinae is a taxonomic subfamily of predatory sea snails, marine gastropod mollusks within the large family Muricidae, the murex snails and rock snails....
Rafinesque, 1815 - MuricopsinaeMuricopsinaeMuricopsinae is a taxonomic subfamily of predatory sea snails, marine gastropod mollusks within the large family Muricidae, the murex snails and rock snails.A study, released in September 2010, showed that the subfamily Muricopsinae is polyphyletic...
Radwin & d'Attilio, 1971 - OcenebrinaeOcenebrinaeOcenebrinae is a taxonomic subfamily of predatory sea snails, marine gastropod mollusks. This subfamily is within the large family Muricidae, which are commonly known as the murex and rock snails....
Cossmann, 1903 - RapaninaeRapaninaeRapaninae is a subfamily of predatory sea snails, marine gastropod mollusks in the family Muricidae. This subfamily was known as Thaidinae until 1993.-Shell description:...
Gray, 1853 - synonym: Thaididae Jousseaume, 1888 - Tripterotyphinae d'Attilio & Hertz, 1988
- TrophoninaeTrophoninaeTrophoninae is a subfamily of predatory sea snails, marine gastropod mollusks in the family Muricidae, the rock snails and their allies.-Genera:According to the World Register of Marine Species, genera within the subfamily Trophoninae include:...
Cossmann, 1903 - Typhinae Cossmann, 1903