Dendrofissurella scutellum
Encyclopedia
Dendrofissurella is a monotypic genus
of minute deepwater keyhole limpet
s, marine
gastropod mollusks in the family
Fissurellidae, the keyhole limpets and slit limpets.
As is shown by the many synonyms, it has taken a long time to recognize that this species (composed of these two subspecies) belongs in its own genus.
of South Africa. D. scutellum scutellum is found on the colder, temperate Atlantic coast while D. scutellum hiantula is found to the east, along the warmer temperate coastline.
and Medusafissurella
with which it shares radular
and shell characters.
The body of Dendrofissurella scutellum is larger than the shell. The anterior part of the shell is narrower than the rest. Both ends of the shell are somewhat raised. The sculpture
of the shell shows fine radial ribs. The mantle fold
s only slightly envelop the edge of the shell. The apical
opening (foramen) is elongate-oval and situated almost in the center. The foot extends behind the shell with a length larger than the shell. The foremost part of the foot (propodium) is elongated by a single, tapering trunk with approximately nine lateral branched that are irregularly placed. This character sets Dendrofissurella apart from Amblychilepas and Medusafissurella.
The large outer lateral tooth of the radula
is quadricuspid ( = with four cusps).
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of minute deepwater keyhole 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...
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 mollusks in the 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...
Fissurellidae, the keyhole limpets and slit limpets.
Taxonomy
Dendrofissurella scutellum is the sole species in this genus. However, two geographic subspecies are recognized :- Dendrofissurella scutellum hiantula (Lamarck, 1822) (synonyms : Fissurella hiantula, Lamarck, 1822; Fissurellidea hiantula, Sowerby II, 1862; Amblychilepas scutellum hiantula, Kilburn and Rippey, 1982; Fissurella incarnata, Krauss, 1848; Fissurellidea incarnata, Sowerby II, 1862; Megatebennus (section Amblychilepas) incarnata, Pilsbry , 1890; Fissurellidea incarnata maculata, Turton, 1962; Fissurellidea multilineata, Turton, 1932 ; Fissurellidea albanyana, Turton, 1932; Fissurellidea nigrostrigata, Turton, 1932)
- Dendrofissurella scutellum scutellum (Gmelin, 1791) (synonyms : Patella scutellum, Gmelin, 1791; Fissurella scutellum, Krauss, 1848; Megatebennus (section Amblychilepas) scutellum, Pilsbry , 1890: Fissurellidaea scutella, Turton, 1932; Amblychilepas scutella, Barnard, 1963; Amblychilepas scutellum, Kensley, 1973; Amblychilepas scutellum scutellum, Kilburn and Rippey, 1982; Fissurellidea sella, Sowerby II, 1862; Megatebennus (section Amblychilepas) sella, Pilsbry, 1890)
As is shown by the many synonyms, it has taken a long time to recognize that this species (composed of these two subspecies) belongs in its own genus.
Distribution
This species occurs in the Cape ProvinceCape Province
The Province of the Cape of Good Hope was a province in the Union of South Africa and subsequently the Republic of South Africa...
of South Africa. D. scutellum scutellum is found on the colder, temperate Atlantic coast while D. scutellum hiantula is found to the east, along the warmer temperate coastline.
Description
Dendrofissurella is closely associated with AmblychilepasAmblychilepas
Amblychilepas 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,...
and Medusafissurella
Medusafissurella
Medusafissurella is a genus of minute deepwater keyhole limpets, marine gastropod mollusks or micromollusks in the family Fissurellidae, the keyhole limpets and slit limpets. -Etymology:...
with which it shares radular
Radula
The 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...
and shell characters.
The body of Dendrofissurella scutellum is larger than the shell. The anterior part of the shell is narrower than the rest. Both ends of the shell are somewhat raised. The sculpture
Sculpture (mollusc)
The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...
of the shell shows fine radial ribs. The mantle fold
Mantle (mollusc)
The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...
s only slightly envelop the edge of the shell. The apical
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
opening (foramen) is elongate-oval and situated almost in the center. The foot extends behind the shell with a length larger than the shell. The foremost part of the foot (propodium) is elongated by a single, tapering trunk with approximately nine lateral branched that are irregularly placed. This character sets Dendrofissurella apart from Amblychilepas and Medusafissurella.
The large outer lateral tooth of the radula
Radula
The 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...
is quadricuspid ( = with four cusps).