''Testacella'' is

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of small to medium-large,

predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

y, air-breathing, land

slug Slug, or land slug, is a common name for any apparently shell-less Terrestrial mollusc, terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced ...

s.MolluscaBase eds. (2022). MolluscaBase. Testacella Lamarck, 1801. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=818595 on 2022-09-13 They are terrestrial

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 ...

s in the family Testacellidae, the shelled slugs. They are not often seen because they live underground. ''Testacella'' is the only genus in the family, in other words it is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

family. ''Testacella'' is the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

of the family Testacellidae.

Distribution

Species within this genus of slugs live in north Africa, southern and western

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, and Britain."Family summary for Testacellidae"
AnimalBase, last modified 8 August 2010, accessed 28 June 2011.

Species

Species within the genus ''Testacella'' include: * Subgenus ''Testacella'' Draparnaud, 1801 * Subgenus ''Testacelloides'' A. J. Wagner, 1914"''Testacelloides'' A.J. Wagner, 1914"

Fauna Europaea Fauna Europaea is a database of the scientific names and distribution of all living multicellular European land and fresh-water animals. It serves as a standard taxonomic source for animal taxonomy within the Pan-European Species directories Infr ...

, last update 27 January 2011, accessed 28 June 2011. * † ''

Testacella asinium ''Testacella'' is genus of small to medium-large, predatory, air-breathing, land slugs.MolluscaBase eds. (2022). MolluscaBase. Testacella Lamarck, 1801. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.p ...

'' Serres, 1827 * '' Testacella bisulcata'' Risso, 1826"Species in genus ''Testacella''"
(n=6).

AnimalBase AnimalBase is a project brought to life in 2004 and is maintained by the University of Göttingen, Germany. The goal of the AnimalBase project is to digitize early zoological literature, provide copyright-free open access to zoological works, and p ...

, accessed 19 January 2011. * '' Testacella bracciai'' Nardi & Bodon, 2011 * † '' Testacella bruntoniana'' Serres, 1851 * † '' Testacella deshayesii'' Michaud, 1855 * '' Testacella fischeriana'' Bourguignat, 1862 * '' Testacella gestroi'' Issel, 1873 * '' Testacella haliotidea'' Lamarck, 1801 - the shelled slug, the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

of the genus * † '' Testacella lartetii'' Dupuy, 1850 * '' Testacella maugei'' Férussac, 1819 * † '' Testacella pedemontana'' Sacco, 1886 * † '' Testacella pontileviensis'' de Morgan, 1920 * † '' Testacella puisseguri'' Schlickum, 1967 * '' Testacella riedeli'' Giusti, Manganelli & Schembri, 1995 * † '' Testacella sandbergeri'' Wenz, 1914 * † '' Testacella schuetti'' Schlickum, 1967 * '' Testacella scutulum'' Sowerby I, 1821 * † '' Testacella zellii'' Klein, 1853 ;Nomen dubium: * ''Testacella antillarum'' Grateloup, 1855 ;Synonyms: * ''Testacella anomala'' Torres Minquez, 1924: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella barcinonensis'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella catalonica'' Pollonera, 1888: synonym of ''Testacella scutulum'' G. B. Sowerby I, 1821 (original name) * ''Testacella dikrangensis'' Godwin-Austen, 1876: synonym of '' Girasia dikrangensis'' (Godwin-Austen, 1876) (original combination) * ''Testacella dubia'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella esserana'' Fagot, 1892: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella europaea'' de Roissy, 1805: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella galliae'' Oken, 1816: synonym of ''Testacella haliotidea'' Draparnaud, 1801 * ''Testacella guadeloupensis'' Lesson, 1838: synonym of '' Omalonyx unguis'' (d'Orbigny, 1836) (junior synonym) * † ''Testacella larteti'' Dupuy, 1850 : synonym of † T''estacella lartetii'' Dupuy, 1850 (incorrect subsequent spelling) * ''Testacella matheronii'' Potiez & Michaud, 1838: synonym of '' Omalonyx unguis'' (d'Orbigny, 1836) (junior synonym) * ''Testacella subtrigona'' Pollonera, 1888: synonym of ''Testacella haliotidea'' Draparnaud, 1801(original name) * ''Testacella vagans'' F. W. Hutton, 1882: synonym of ''Testacella maugei'' Férussac, 1819

Description

These slugs have a very small, ear-shaped

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine ani ...

, which is situated far back on their bodies. In the family Testacellidae, the number of

haploid Ploidy () is the number of complete sets of chromosomes in a cell (biology), cell, and hence the number of possible alleles for Autosome, autosomal and Pseudoautosomal region, pseudoautosomal genes. Here ''sets of chromosomes'' refers to the num ...

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s lies between 31 and 35 (according to the values in this table).Barker G. M.: Gastropods on Land: ''Phylogeny, Diversity and Adaptive Morphology''. in Barker G. M. (ed.):
The biology of terrestrial molluscs
'. CABI Publishing, Oxon, UK, 2001, . 1-146, cited pages: 139 and 142.

Habitat

These slugs are rarely observed, but they tend to live in gardens and farms where there is rich soil and a lot of

earthworm An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they we ...

Life habits

These slugs live underground and hunt earthworms. They are usually only seen when they are forced up to the surface because the soil has become completely saturated with rain. Testacella

References

External links

Lamarck, J. B. (1801). Système des animaux sans vertèbres, ou tableau général des classes, des ordres et des genres de ces animaux; Présentant leurs caractères essentiels et leur distribution, d'apres la considération de leurs rapports naturels et de leur organisation, et suivant l'arrangement établi dans les galeries du Muséum d'Histoire Naturelle, parmi leurs dépouilles conservées; Précédé du discours d'ouverture du Cours de Zoologie, donné dans le Muséum National d'Histoire Naturelle l'an 8 de la République. Published by the author and Deterville, Paris: viii + 432 pp

"''Testacella'' Species"

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