Fissurellinae
Encyclopedia
The subfamily Fissurellinae, common name
the keyhole limpets and slit limpets, is a taxonomic subfamily of limpet
-like sea snail
s, marine
gastropod molluscs in the family Fissurellidae.
Of the two subfamilies in the Fissurellidae, the subfamily Fissurellinae is the most recently evolved; its earliest known species date back to the Cenozoic
.
The following genera in this subfamily have characteristically a body that tends to be larger than the shell.
They have sometimes been confused with genera in the emarginuline tribe Fissurellideini.
Other genera include : Altrix
- Clathrosepta
- Cornisepta
- Cosmetalepas
- Dendrofissurella - Elegidion - Fissurella
- Laevinesta
- Lucapina
- Macroschisma - Manganesepta
- Montfortula
- Montfortulana - Parmaphoridea - Parmophoridea
- Profundisepta
The characteristics that distinguish them from the subfamily Emarginulidae are the following :
A molecular phylogeny
however has shown that Fissurellinae (Diodora and Fissurella were examined) is paraphyletic with respect to Emarginulinae. This is somewhat surprising as the subfamily Emarginulinae (shells with an open slit) is generally accepted to be basal to the subfamily Fissurellinae (shells with an apical opening)
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 keyhole limpets and slit limpets, is a taxonomic subfamily of limpet
Limpet
Limpet is a common name for a number of different kinds of saltwater and freshwater snails ; it is applied to those snails that have a simple shell which is more or less conical in shape, and either is not spirally coiled, or appears not to be coiled in the adult snails.The name limpet is most...
-like 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 family Fissurellidae.
Of the two subfamilies in the Fissurellidae, the subfamily Fissurellinae is the most recently evolved; its earliest known species date back to the Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...
.
The following genera in this subfamily have characteristically a body that tends to be larger than the shell.
- AmblychilepasAmblychilepasAmblychilepas is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Distribution:The species from this genus can be found in temperate waters of Australia, except Amblychilepas platyactis that is found along the Atlantic coast of the Cape Peninsula,...
- Dendrofissurella
- MedusafissurellaMedusafissurellaMedusafissurella is a genus of minute deepwater keyhole limpets, marine gastropod mollusks or micromollusks in the family Fissurellidae, the keyhole limpets and slit limpets. -Etymology:...
They have sometimes been confused with genera in the emarginuline tribe Fissurellideini.
Other genera include : Altrix
Altrix
Altrix is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Aktrix include:* Altrix trifolium* Altrix altior...
- Clathrosepta
Clathrosepta
Clathrosepta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Clathrosepta include:* Clathrosepta becki McLean & Geiger, 1998...
- Cornisepta
Cornisepta
Cornisepta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Cornisepta include:* Cornisepta acuminata...
- Cosmetalepas
Cosmetalepas
Cosmetalepas is a genus of minute deepwater keyhole limpets, marine gastropod mollusks or micromollusks in the family Fissurellidae, the keyhole limpets and slit limpets.-Species:* Cosmetalepas africana Tomlin, 1926...
- Dendrofissurella - Elegidion - Fissurella
Fissurella
Fissurella is a genus of small to medium-sized sea snails or limpets, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.- Ecology :...
- Laevinesta
Laevinesta
Laevinesta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Laevinesta include:* Laevinesta atlantica...
- Lucapina
Lucapina
Lucapina is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Lucapina include:* Lucapina adspersa * Lucapina aegis...
- Macroschisma - Manganesepta
Manganesepta
Manganesepta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Manganesepta include:* Manganesepta hessleri McLean & Geiger, 1998...
- Montfortula
Montfortula
Montfortula is a genus of keyhole limpets, marine gastropod molluscs in the family Fissurellidae.-References:* Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1...
- Montfortulana - Parmaphoridea - Parmophoridea
Parmophoridea
Parmophoridea is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Parmophoridea include:* Parmophoridea mawsoni...
- Profundisepta
Profundisepta
Profundisepta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the keyhole limpets.-Species:Species within the genus Profundisepta include:* Profundisepta alicei Profundisepta is a genus of sea snails, marine gastropod mollusks in the family Fissurellidae, the...
The characteristics that distinguish them from the subfamily Emarginulidae are the following :
- the rachidian plate of the radulaRadulaThe radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
has a broad base and a narrow tip - the outer lateral tooth in the radula is so long that it is aligned with the lateral teeth from the row above
- the shell muscle lacks an inwardly directed hook-shaped process.
A molecular phylogeny
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
however has shown that Fissurellinae (Diodora and Fissurella were examined) is paraphyletic with respect to Emarginulinae. This is somewhat surprising as the subfamily Emarginulinae (shells with an open slit) is generally accepted to be basal to the subfamily Fissurellinae (shells with an apical opening)