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Slug Gun
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 shell, or only a small internal shell, particularly sea slugs and semi-slugs (this is in contrast to the common name ''snail'', which applies to gastropods that have a coiled shell large enough that they can fully retract their soft parts into it). Various Taxonomy (biology), taxonomic families of land slugs form part of several quite different evolutionary lineages, which also include snails. Thus, the various families of slugs are not closely related, despite the superficial similarity in overall body form. The shell-less condition has arisen many times independently as an example of convergent evolution, and thus the category "slug" is Polyphyly, polyphyletic. Taxonomy Of the six orders of Pulmonata, two – the Onchidiacea and Soleoli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Britain
Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European islands by area, largest European island, and the List of islands by area, ninth-largest island in the world. It is dominated by a maritime climate with narrow temperature differences between seasons. The island of Ireland, with an area 40 per cent that of Great Britain, is to the west – these islands, along with over List of islands of the British Isles, 1,000 smaller surrounding islands and named substantial rocks, comprise the British Isles archipelago. Connected to mainland Europe until 9,000 years ago by a land bridge now known as Doggerland, Great Britain has been inhabited by modern humans for around 30,000 years. In 2011, it had a population of about , making it the world's List of islands by population, third-most-populous islan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-slug
Semi-slugs, also spelled semislugs, are land gastropods whose shells are too small for them to retract into, but not quite vestigial. The shell of some semi-slugs may not be easily visible on casual inspection, because the shell may be covered over with the mantle. This is a type of gastropod that is intermediate between a slug (without an external shell) and a land snail (with a large enough shell to retract completely into). There exist a number of gastropod families that have semi-slug species.Breure A. S. H. (2010). "The rediscovery of a semi-slug: ''Coloniconcha prima'' Pilsbry, 1933 (Gastropoda, Pleurodontidae) from Hispaniola". ''Basteria'' 74(4-6): 78-86. There exist about 1,000 species of semi-slugs in comparison to about only 500 species of slugs.Burton D. W. (1982). "How to be sluggish". ''Tuatara'' 25(2): 48-63HTM Examples Semi-slugs have a worldwide distribution and have evolved in several families; genera include: * Palearctic and Nearctic ** family Parmacell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acavoidea
The Acavoidea are a taxonomic superfamily of air-breathing land snails and slugs, terrestrial pulmonate gastropod mollusks in the informal group Sigmurethra. This taxonomy was based on the study by Nordsieck, published in 1986. Taxonomy Families within the superfamily Acavoidea are as follows: *Family Acavidae Pilsbry, 1895 *Family Caryodidae Conolly, 1915 *Family Dorcasiidae Conolly, 1915 *Family Macrocyclidae Thiele, 1926 *Family Megomphicidae H.B. Baker, 1930 *Family Strophocheilidae Strophocheilidae is a Taxonomy (biology), taxonomic family (biology), family of air-breathing land snails, terrestrial molluscs, terrestrial pulmonate gastropod mollusks in the superfamily Acavoidea (according to the Taxonomy of the Gastropoda (B ... Pilsbry, 1902 References Stylommatophora Gastropod superfamilies {{Heterobranchia-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pupilloidea
Pupilloidea is a superfamily of small and very small air-breathing land snails, terrestrial gastropods in the infraorder '' Pupilloidei''. They are diverse in morphology, habitat, and ecological roles. Description They are characterized by their small, often cylindrical, ovate, or elongate shells. Their shells can range from smooth to ribbed or striated. They are generally tiny, ranging from a few millimeters to about a centimeter in length. The aperture often has denticles (teeth) or lamellae, which may play roles in predator deterrence or structural support. The margin of the aperture often features a well-defined peristome, sometimes thickened or reflected. Distribution Species in this superfamily are cosmopolitan, found on every continent except Antarctica. They can be found in dry and arid regions to temperate forests and even tropical zones. Taxonomy This superfamily contains the following families: * Achatinellidae Gulick, 1873 * Agardhiellidae Harl & Páll-Gergely, 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlicopoidea
Pupilloidea is a superfamily of small and very small air-breathing land snails, terrestrial gastropods in the infraorder ''Pupilloidei''. They are diverse in morphology, habitat, and ecological roles. Description They are characterized by their small, often cylindrical, ovate, or elongate shells. Their shells can range from smooth to ribbed or striated. They are generally tiny, ranging from a few millimeters to about a centimeter in length. The aperture often has denticles (teeth) or lamellae, which may play roles in predator deterrence or structural support. The margin of the aperture often features a well-defined peristome, sometimes thickened or reflected. Distribution Species in this superfamily are cosmopolitan, found on every continent except Antarctica. They can be found in dry and arid regions to temperate forests and even tropical zones. Taxonomy This superfamily contains the following families: * Achatinellidae Gulick, 1873 * Agardhiellidae Harl & Páll-Gergely, 2017 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthurethra
Orthurethra is a clade of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Stylommatophora. In the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, Orthurethra is treated as an informal group and subclade of Stylommatophora. In the revised taxonomy of 2017 this taxon is no longer supported and has been replaced by the infraorder Pupilloidei.Bouchet P., Rocroi J.P., Hausdorf B., Kaim A., Kano Y., Nützel A., Parkhaev P., Schrödl M. & Strong E.E. (2017). Revised classification, nomenclator and typification of gastropod and monoplacophoran families. Malacologia. 61(1-2): 1-526 Superfamilies and families Superfamilies and families within the clade Orthurethra: (Families that are exclusively fossil are indicated with a dagger †) *Superfamily Pupilloidea * Achatinellidae Gulick, 1873 * Agardhiellidae Harl & Páll-Gergely, 2017 * Amastridae Pilsbry, 1910 * Argnidae Hudec, 1965 * Azecidae H. Watson, 1920 * Cerastidae Wenz, 1923 * Chondrin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellobiidae
Ellobiidae, common name the hollow-shelled snails, is a family of small air-breathing land, marine, and brackish snails; pulmonate gastropod mollusks in the clade Eupulmonata.Bouchet, P. (2012). Ellobiidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=198 on 2012-08-19 Ellobiidae is the only family in the superfamily Ellobioidea, according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Anatomy In this family, the number of haploid chromosomes lies between 16 and 20 (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. They have a distinctive mode of locomotion arising due to a split sole. The front part of the sole adheres to the substrate and then the rear part of the sole is drawn up to the front part. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthobranch
Opisthobranchs () is a now informal name for a large and diverse group of specialized complex gastropods which used to be united in the subclass Opisthobranchia. That taxon is no longer considered to represent a monophyletic grouping. Euopisthobranchia is a taxon containing a revised collection of opisthobranchs, and that taxon is considered monophyletic. Euopisthobranchia does not include some "traditional" opisthobranchs such as the Sacoglossa and the Acochlidiacea. The subclass Heterobranchia now contains all the species which used to be assigned to Opisthobranchia, plus all the species in the Pulmonata. The subclass Opisthobranchia included species in the order Cephalaspidea (bubble shells and headshield slugs), the sacoglossans, anaspidean sea hares, pelagic sea angels, sea butterflies, and many families of the Nudibranchia. ''Opisthobranch'' means "gills behind" (and to the right) of the heart. In contrast, ''Prosobranch'' means ''gills in front'' (of the heart). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonata
Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includes many land and freshwater families, and several marine families. The taxon Pulmonata as traditionally defined was found to be polyphyletic in a molecular study per Jörger ''et al.'', dating from 2010. Pulmonata are known from the Carboniferous period to the present. Pulmonates have a single atrium and kidney, and a concentrated symmetrical nervous system. The mantle cavity is on the right side of the body, and lacks gills, instead being converted into a vascularised lung. Most species have a shell, but no operculum, although the group does also include several shell-less slugs. Pulmonates are hermaphroditic, and some groups possess love darts. Linnean taxonomy The taxonomy of this group according to the taxonomy of the Gastropoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphyly
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of convergent evolution. The arrangement of the members of a polyphyletic group is called a polyphyly .. ource for pronunciation./ref> It is contrasted with monophyly and paraphyly. For example, the biological characteristic of warm-bloodedness evolved separately in the ancestors of mammals and the ancestors of birds; "warm-blooded animals" is therefore a polyphyletic grouping. Other examples of polyphyletic groups are algae, C4 photosynthetic plants, and edentates. Many taxonomists aim to avoid homoplasies in grouping taxa together, with a goal to identify and eliminate groups that are found to be polyphyletic. This is often the stimulus for major revisions of the classification schemes. Researchers concerned m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
