''Steromphala pennanti'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of small

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

in the family

Trochidae The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles ...

, the top snails.MolluscaBase eds. (2020). MolluscaBase. Steromphala pennanti (Philippi, 1846). Accessed through: World Register of Marine Species at: http://marinespecies.org/aphia.php?p=taxdetails&id=1039846 on 2020-12-30 The species was named in honor of

Thomas Pennant Thomas Pennant (14 June Old Style, OS 172616 December 1798) was a Welsh natural history, naturalist, traveller, writer and antiquarian. He was born and lived his whole life at his family estate, Downing Hall near Whitford, Flintshire, in Wales ...

(1726 – 1798), a Welsh naturalist.

Description

The size of the shell varies between 10 mm and 16 mm. The shell is more depressed than ''

Gibbula cineraria ''Steromphala cineraria'' is a species of small sea snail, a marine gastropod mollusc in the family Trochidae, the top snails.MolluscaBase eds. (2020). MolluscaBase. Steromphala cineraria (Linnaeus, 1758). Accessed through: World Register of ...

'', and (although the base is flatter) never inclined to a pyramidal form. The spiral ridges are sharper and fewer, especially in the young. The present species is usually more widely umbilicate and broader than ''Gibbula cineraria''. The coloring is different; both have a similar kind of marking, but in the present species the longitudinal rays or streaks are red, besides being broader and not half so many as in the other species. And they are sometimes zigzag, instead of being broken into spots or interrupted by the

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

. This species is striped, the other lineated. Just within the outer lip are two borders, one of yellow, the other of green variegated by red spots. This edging is minutely tubercled like shagreen.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
(described as ''Gibbula obliquata'')

Distribution

This species occurs in the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...

and off

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

References

* Gmelin J. F., 1791: ''Caroli Linnaei systema Naturae per regna tria naturae. Editio decimatertia, aucta, reformata, Vermes Testacea'' ; Leipzig ipsiae1 (6): 3021-3910 * Lowe, R. T. (1861). ''A list of shells observed or collected at Mogador and in its immediate environs, during a few days' visit to the place, in April 1859''. Proceedings of the Zoological Society of London. 1860: 169-204 1860" London. * Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). ''European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification''. Collection Patrimoines Naturels, 50: pp. 180–213

External links

www.anemoon.org
* * ibbula pennanti (Philippi, 1846) Aradas A., 1847: ''Descrizione delle conchiglie fossili di Gravitelli presso Messina'' ; Atti dell'Accademia Gioenia di Scienze Naturali (2) 4: 57-88
Monterosato T. A. (di), 1888-1889: ''Molluschi del Porto di Palermo. Specie e varietà''; Bullettino della Società Malacologica Italiana, Pisa 13 (1888 889?">Monterosato T. A. (di), 1888-1889: ''Molluschi del Porto di Palermo. Specie e varietà''; Bullettino della Società Malacologica Italiana, Pisa 13 (1888[1889?
: 161-180 14 (1889): 75-81
Affenzeller S., Haar N. & Steiner G. (2017). Revision of the genus complex Gibbula: an integrative approach to delineating the Eastern Mediterranean genera Gibbula Risso, 1826, Steromphala Gray, 1847, and Phorcus Risso, 1826 using DNA-barcoding and geometric morphometrics (Vetigastropoda, Trochoidea). Organisms Diversity & Evolution. 17(4): 789-812
{{Taxonbar">from1=Q61701160, from2=Q2072993 pennanti Gastropods described in 1846 Taxa named by Rodolfo Amando Philippi