''Stellaria testigera'', common name finger carrier shell, is a
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of large
sea snail
Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...
gastropod
Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, freshwater, and fro ...
mollusk
Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...
in the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Xenophoridae
Xenophoridae, common name, commonly called carrier shells, is a family (biology), family of medium-sized to large sea snails, marine (ocean), marine gastropod mollusks in the clade Littorinimorpha.
Distribution
The Xenophorids live on sand and ...
''Stellaria testigera profunda'' is present in the Gulf of Aden and in North East Africa,S. t. profunda at Gastropods /ref> while ''Stellaria testigera digitata'' can be found in Senegal and Western Africa.S.t. digitata at Gastropods /ref>
Description
Shells of ''Stellaria testigera profunda'' can reach a size of , while in ''Stellaria testigera digitata'' they can reach . These shells are characterized by the expanded peripherical flange, the presence of digitations and the smooth dorsal surface.
Fossil record
Fossils of ''Stellaria testigera'' are found in marine strata from the
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
to
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Tertiary Xenophoridae (Gastropoda) of western South America The Nautilus. - Bailey-Matthews Shell Museum - American Malacologists, Inc. -
Delaware Museum of Natural History
The Delaware Museum of Nature & Science (DMNH, formerly Delaware Museum of Natural History) is a museum located in Wilmington, Delaware. The museum was founded in 1957 by John Eleuthere du Pont near Greenville, Delaware; it opened in 1972 on a s ...