Terebellum terebellum, common name the Terebellum conch, is a species of sea snail, a marine gastropod mollusk in the family Seraphsidae, 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 region. Phylogeny The phylogenetic relationships among the Stromboidea have been accessed in 2005, by Simone. He proposed a cladogram (a tree of descent) based on an extensive morpho-anatomical analysis of representatives of Aporrhaidae, Strombidae, Xenophoridae and Struthiolariidae. In his analysis, Simone recognized Strombidae as a monophyletic taxon supported by 13 synapomorphies (traits that are shared by two or more taxa and their most recent common ancestor), with at least eight distinct genera. He considered the genus Terebellum as the most basal taxon, distinguished from the remaining strombids by 13 synapomorphies, including a rounded foot. Though the genus Tibia 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. [Suping]. (2016). Fauna Sinica. Invertebrata 56. Mollusca: Gastropoda: Strombacea and Naticacea. Beijing: Science Press. 317 pp., 10 pls. External links Seraphsidae Gastropods described in 1767 Taxa named by Carl Linnaeus