''Terebellum terebellum'',

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...

the Terebellum conch, 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), ...

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 ...

, a marine

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 ...

Seraphsidae Seraphsidae is a family of small to medium-sized sea snails, marine gastropod molluscs in the superfamily Stromboidea The Stromboidea, originally named the Strombacea by Rafinesque in 1815, is a superfamily of medium-sized to very large sea ...

, the true conchs.

Description

''T. terebellum'' is a very active animal that can quickly bury itself in sand or swim away from danger. It uses its foot like a propeller to swim. Its shell is thin and fragile.

Distribution

''T. terebellum'' are found throughout the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

region.

Phylogeny

The phylogenetic relationships among the Stromboidea have been accessed in 2005, by Simone. He proposed a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

(a tree of descent) based on an extensive

morpho Morpho may refer to: * ''Morpho'' (genus), a genus of butterflies * Morpho (VTOL), a Swiss prototype drone * Morpho (company) IDEMIA (formerly known as OT-Morpho) is a French multinational technology company headquartered in Courbevoie, Fra ...

anatomical Anatomy () is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old scien ...

analysis of representatives of

Aporrhaidae Aporrhaidae is a family of sea snails commonly called the "pelican's foot snails." The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classif ...

, Strombidae,

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 ...

and

Struthiolariidae Struthiolariidae is a family (biology), family of small to medium-sized sea snails, marine (ocean), marine gastropod molluscs in the superfamilia, superfamily Stromboidea.Bouchet, P.; Rosenberg, G. (2014). Struthiolariidae Gabb, 1868. Accessed th ...

. In his analysis, Simone recognized Strombidae as a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

taxon supported by 13

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to ...

(traits that are shared by two or more

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

and their

most recent common ancestor A most recent common ancestor (MRCA), also known as a last common ancestor (LCA), is the most recent individual from which all organisms of a set are inferred to have descended. The most recent common ancestor of a higher taxon is generally assu ...

), with at least eight distinct genera. He considered the genus '' Terebellum'' as the most basal

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

, distinguished from the remaining strombids by 13 synapomorphies, including a rounded foot. Though the genus ''

Tibia The tibia (; : tibiae or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two Leg bones, bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outsi ...

'' was left out of the analysis, Simone regarded it as probably closely related to '' Terebellum'', apparently due to some well known morphological similarities between them.

References

* Walls, J.G. (1980). ''Conchs, tibias and harps. A survey of the molluscan families Strombidae and Harpidae''. T.F.H. Publications Ltd, Hong Kong. * Rosenberg, G. 1992.'' Encyclopedia of Seashells''. Dorset: New York. 224 pp. page(s): 67 * Liverani V. (2014) The superfamily Stromboidea. Addenda and corrigenda. In: G.T. Poppe, K. Groh & C. Renker (eds), A conchological iconography. pp. 1–54, pls 131–164. Harxheim: Conchbooks. * Poppe G.T. & Tagaro S. (2016). New marine mollusks from the central Philippines in the families Aclididae, Chilodontidae, Cuspidariidae, Nuculanidae, Nystiellidae, Seraphsidae and Vanikoridae. Visaya. 4(5): 83-103 * Zhang S.-P. uping (2016). Fauna Sinica. Invertebrata 56. Mollusca: Gastropoda: Strombacea and Naticacea. Beijing: Science Press. 317 pp., 10 pls. Seraphsidae Gastropods described in 1767 Taxa named by Carl Linnaeus {{Strombidae-stub