Vermetidae
Encyclopedia
Vermetidae, common name
the worm snails or worm shells, is a taxonomic family
of small to medium-sized sea snail
s, marine
gastropod molluscs in the clade
Littorinimorpha
.
The shells of the Vermetidae are extremely irregular, and do not resemble the average snail shell, hence the common name "worm shells" or "worm snails".
They usually grow cemented onto a hard surface, or cemented together in colonies.
s; instead they have very irregular elongated tubular shells which are moulded to, and cemented to, a surface of attachment such as a rock or another shell and so on. In the adult the apertural
part of the shell is usually free, with the opening directed upward. Some species have an operculum
and some do not. Damaged sections of the shell can be sealed off by calcareous septa when necessary.
Some vermetids are solitary, whereas others live in colonies, partially cemented together. The shells of species within this family vary greatly and can sometimes be extremely challenging to identify.
tube worms, for example the Serpulidae
, can sometimes be casually misidentified as empty vermetid shells, and vice versa. The difference is that vermetid shells are shiny inside and have 3 shell layers, whereas the annelid worm tubes are dull inside and have only 2 shell layers.
within clade Littorinimorpha
.
The following two subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005)
:
Family Vermetidae Rafinesque, 1815
This classification of the Vermetoidea has been somewhat controversial. Studies, based on sperm ultrastructure, and on molecular data clearly place it within the clade Littorinimorpha. However, there are still a number of authors that place it within the superfamily Cerithioidea
. The genera Campanile and Serpulorbis from a clade that is sister to the Cerithioidea, as shown in a study by Lydeard et al. (2002).
Vermetinae
† Laxispirinae
Dendropomatinae
subfamily ?
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...
the worm snails or worm shells, is a 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 medium-sized 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, marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
gastropod molluscs in the clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
Littorinimorpha
Littorinimorpha
Littorinimorpha is a large clade of gastropods within Hypsogastropoda consisting primarily of marine species, but also aquatic and terrestrial species as well....
.
The shells of the Vermetidae are extremely irregular, and do not resemble the average snail shell, hence the common name "worm shells" or "worm snails".
They usually grow cemented onto a hard surface, or cemented together in colonies.
Shell description
These snails do not have typical regularly coiled gastropod shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
s; instead they have very irregular elongated tubular shells which are moulded to, and cemented to, a surface of attachment such as a rock or another shell and so on. In the adult the apertural
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
part of the shell is usually free, with the opening directed upward. Some species have an 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...
and some do not. Damaged sections of the shell can be sealed off by calcareous septa when necessary.
Some vermetids are solitary, whereas others live in colonies, partially cemented together. The shells of species within this family vary greatly and can sometimes be extremely challenging to identify.
Comparison with annelid worm tubes
The empty calcareous tubes of certain marine annelidAnnelid
The annelids , formally called Annelida , are a large phylum of segmented worms, with over 17,000 modern species including ragworms, earthworms and leeches...
tube worms, for example the Serpulidae
Serpulidae
Serpulidae is a family of sessile, tube-building annelid worms in the class Polychaeta. The members of this family differ from the sabellid tube worms in that they have a specialized operculum that blocks the entrance of their tubes when they withdraw into the tubes. In addition, serpulids secrete...
, can sometimes be casually misidentified as empty vermetid shells, and vice versa. The difference is that vermetid shells are shiny inside and have 3 shell layers, whereas the annelid worm tubes are dull inside and have only 2 shell layers.
2005 taxonomy
Vermetidae have been recognized in as the only family in the superfamily Vermetoidea in the taxonomy of Bouchet & Rocroi (2005)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...
within clade Littorinimorpha
Littorinimorpha
Littorinimorpha is a large clade of gastropods within Hypsogastropoda consisting primarily of marine species, but also aquatic and terrestrial species as well....
.
The following two subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005)
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...
:
Family Vermetidae Rafinesque, 1815
- Subfamily Vermetinae Rafinesque, 1815
- Subfamily Dendropomatinae Bandel & Kowalke, 1997
This classification of the Vermetoidea has been somewhat controversial. Studies, based on sperm ultrastructure, and on molecular data clearly place it within the clade Littorinimorpha. However, there are still a number of authors that place it within the superfamily Cerithioidea
Cerithioidea
The Cerithioidea is a superfamily of marine, brackish water and freshwater gastropod containing more than 200 genera. The Cerithoidea are included in the clade Sorbeoconcha. The original name of this superfamily was Cerithiacea, in keeping with common superfamily endings at the time.- Ecology...
. The genera Campanile and Serpulorbis from a clade that is sister to the Cerithioidea, as shown in a study by Lydeard et al. (2002).
2006 taxonomy
Bandel (2006) have established a new subfamily Laxispirinae and he have been recognized three subfamilies of Vermetidae:- Subfamily Vermetinae Rafinesque, 1815
- Subfamily † Laxispirinae Bandel, 2006
- Subfamily Dendropomatinae Bandel & Kowalke, 1997
Genera
Genera within the family Vermetidae include:Vermetinae
- VermetusVermetusVermetus is a genus of sea snails, marine gastropod mollusks in the family Vermetidae, the worm snails or worm shells.-Species:Species within the genus Vermetus include:* Vermetus afer * Vermetus alii Hadfield & Kay, 1972...
Daudin, 1800 - type genus - CerithiovermetusCerithiovermetusCerithiovermetus is a genus of sea snails, marine gastropod mollusks in the family Vermetidae, the worm snails or worm shells.-Species:Species within the genus Cerithiovermetus include:* Cerithiovermetus aqabensis Bandel, 2006...
Bandel, 2006
† Laxispirinae
- † Laxispira Gabb, 1877 - Late Cretaceous, type genus of the subfamily
Dendropomatinae
- DendropomaDendropomaDendropoma is a genus of irregularly-coiled sea snails known as "worm shells" or "worm snails". These are marine gastropod molluscs in the family Vermetidae, the worm snails.-Species:...
MörchOtto Andreas Lowson MörchOtto Andreas Lowson Mörch was a biologist, specifically a malacologist. He lived in Sweden, in Denmark, and in France.- Taxa described :Bibliography and taxa described by Otto Andreas Lowson Mörch include:...
, 1861 - type genus of the subfamily
subfamily ?
- BivoniaBivoniaBivonia is a genus of sea snails, marine gastropod mollusks in the family Vermetidae, the worm snails or worm shells....
Gray, 1842 - EualetesEualetesEualetes is a genus of sea snails, marine gastropod mollusks in the family Vermetidae, the worm snails or worm shells....
Keen, 1971 - NovastoaNovastoaNovastoa is a genus of sea snails, marine gastropod molluscs in the family Vermetidae, the worm snails.-Species:Species within the genus Novastoa include:* Novastoa lamellosa -References:...
Finlay, 1926 - PetaloconchusPetaloconchusPetaloconchus is a genus of sea snails, marine gastropod mollusks in the family Vermetidae, the worm snails or worm shells.-Species:Species within the genus Petaloconchus include:* Petaloconchus adansoni...
I. Lea, 1843 - SerpulorbisSerpulorbisSerpulorbis is a genus of sea snails known as worm shells or worm snails. These are marine gastropod molluscs in the family Vermetidae, the wormsnails. Unlike some other vermetids, the species in this genus have no operculum....
Sassi, 1827 - Spiroglyptus Daudin, 1800
- StephopomaStephopomaStephopoma is a genus of sea snails, marine gastropod molluscs in the family Siliquariidae, the "slit worm shells" or "slit worm snail.-Species:Species within the genus Stephopoma include:* Stephopoma abrolhosense...
Mörch, 1860 - Thylaeodus Mörch, 1860
External links
- Powell A. W. B.Arthur William Baden PowellDr Arthur William Baden Powell CBE was a New Zealand malacologist, naturalist and palaeontologist, a major influence in the study and classification of New Zealand molluscs through much of the twentieth century. He was known to his friends and family by his third name, "Baden".Powell was born at...
, New Zealand Mollusca, William Collins Publishers LtdHarperCollinsHarperCollins is a publishing company owned by News Corporation. It is the combination of the publishers William Collins, Sons and Co Ltd, a British company, and Harper & Row, an American company, itself the result of an earlier merger of Harper & Brothers and Row, Peterson & Company. The worldwide...
, Auckland, New Zealand 1979 ISBN 0-00-216906-1 - R. Tucker Abbott, 1986. Seashells of North America, St. Martin's Press, New York