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Vetigastropoda
Vetigastropoda is a major taxonomic group of sea snails, marine gastropod mollusks that form a very ancient lineage. Taxonomically the Vetigastropoda are sometimes treated as an order, although they are treated as an unranked clade in Bouchet and Rocroi, 2005. Vetigastropods are considered to be among the most primitive living gastropods, and are widely distributed in all oceans of the world. Their habitats range from the deep sea to intertidal zones. Many have shells with slits or other secondary openings. One of their main characteristics is the presence of intersected crossed platy shell structure. Most vetigastropods have some bilateral asymmetry of their organ systems. Description Vetigastropods range in size from approximately 0.08 in (2 mm) long in the case of Scissurelloidea or Skeneoidea, to more than 11.8 in (300 mm) in length, as with the Haliotoidea. External colours and patterns are typically drab, but such groups as the Tricolioidea and some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleurotomarioidea
Pleurotomarioidea is a superfamily of small to large marine gastropods included in the order Pleurotomariida of the subclass Vetigastropoda. These are the slit shells, originally named Pleurotomariacea, in keeping with the convention for naming superfamilies at the time. This updated version of the name for the taxon is usually used by students of the living Mollusca. Paleontologists often still use the name Pleurotomariacea instead. Evolutionary history Forming the first evidence of crown-group gastropods when they appeared in the Upper Cambrian, the fossil record of the Pleurotomarioideans has no substantial gaps until today. The group took quite a hit at the Cretaceous–Paleogene boundary (K–T boundary), with only the Pleurotomariidae surviving the Cretaceous–Paleogene extinction event – and then only in deep waters. Living representatives of the group were first discovered in the mid-19th century, and their unusual mix of primitive and derived characte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 from the land. There are many thousands of species of sea snails and sea slug, slugs, as well as freshwater snails, freshwater limpets, land snails and slugs. The class Gastropoda is a diverse and highly successful class of mollusks within the phylum Mollusca. It contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Furongian, Late Cambrian. , 721 family (taxonomy), families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently neontology, extant living fossil, with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scissurelloidea
Scissurelloidea is a taxonomic superfamily of small sea snails, marine gastropod mollusks or micromollusks in the subclass Vetigastropoda. Scissurelloidea is a taxonomic superfamily of small sea snails, marine gastropod mollusks or micromollusks in the clade Vetigastropoda. Taxonomy This superfamily consists of two following families (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005): *Family Scissurellidae Gray, 1847 *Family Anatomidae McLean, 1989 Geiger (2009)Geiger D. L.(8 May 2009) "A new species of Depressizona and the family rank of Depressizonidae". ''Zootaxa'' 2059: 57-59abstract updated two other subfamilies to family level: Superfamily Scissurelloidea: * Family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy Of The Gastropoda (Bouchet & Rocroi, 2005)
The taxonomy of the Gastropoda as it was revised in 2005 by Philippe Bouchet and Jean-Pierre Rocroi is a system for the scientific classification of gastropod mollusks (Gastropods are a taxonomic class of animals which consists of snails and slugs of every kind, from the land, from freshwater, and from saltwater). The paper setting out this taxonomy was published in the journal '' Malacologia''. The system encompasses both living and extinct groups, as well as some fossils whose classification as gastropods is uncertain. The Bouchet & Rocroi system was the first complete gastropod taxonomy that primarily employed the concept of clades, and was derived from research on molecular phylogenetics; in this context a clade is a "natural grouping" of organisms based upon a statistical cluster analysis. In contrast, most of the previous overall taxonomic schemes for gastropods relied on morphological features to classify these animals, and used taxon ranks such as order, superorder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliotoidea
Haliotoidea is a superfamily of sea snails, marine gastropod mollusks in the subclass Vetigastropoda (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International Journal of Malacology, 47(1-2). ConchBooks: Hackenheim, Germany. . ISSN 0076-2997. 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278MolluscaBase eds. (2022). MolluscaBase. Haliotoidea Rafinesque, 1815. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=156488 on 2022-06-04 Families The superfamily Haliotoidea contains (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005) two families: * The recent family Haliotidae, also known as abalones * The extinct family Temnotropidae Temnotropidae is an extinct family of fossil sea snails, marine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trochoidea (superfamily)
Trochoidea is a superfamily of small to very large vetigastropod sea snails with gills and an operculum.Gofas, S. (2013). Trochoidea. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=156489 on 2013-06-29 Species within this superfamily have nacre as the inner shell layer. The families within this superfamily include the Trochidae, the top snails. This superfamily is the largest vetigastropodan superfamily, containing more than 2,000 species. This taxon is ''not'' the same as a pulmonate land snail genus which is spelled the same way: ''Trochoidea'' (genus). Taxonomy 2005 taxonomy This superfamily consisted of nine following families (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005): * Trochidae Rafinesque, 1815 * Calliostomatidae Thiele, 1924 (1847) * † Elasmonematidae Knight, 1956 * † Eucochlidae Bandel, 2002 * † Microdomatidae Wenz, 1938 * † Proconulidae Cox, 1960 * Solar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discohelix Tunisiensis Apical
''Discohelix'' is a genus of extinct sea snails, marine gastropod mollusks in the family Discohelicidae.Bouchet, P. (2015). ''Discohelix'' Dunker, 1847 †. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=536262 on 2016-12-04 Species The following species were brought into synonymy: * ''Discohelix hedleyi'' Mestayer, 1916 accepted as '' Zerotula hedleyi'' (Mestayer, 1916) The following species are alternate representation: * ''Discohelix retifera'' Dall, 1892 represented as '' Pseudotorinia retifera'' (Dall, 1892) (alternate representation), in turn accepted as '' Pseudotorinia'' (an unresolved species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...). References External links * B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 distinguished from snails primarily by the absence of a visible Gastropod shell, shell. Definition Determining whether some gastropods should be called sea snails is not always easy. Some species that live in brackish water (such as certain Neritidae, neritids) can be listed as either freshwater snails or marine snails, and some species that live at or just above the high tide level (for example, species in the genus ''Truncatella (gastropod), Truncatella'') are sometimes considered to be sea snails and sometimes listed as land snails. Anatomy Sea snails are a very large and diverse group of animals. Most snails that live in salt water respire using a gill or gills; a few species, though, have a lung, are intertidal, and are active only at low tide w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusc
Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The number of additional fossil species is estimated between 60,000 and 100,000, and the proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine biology, marine phylum, comprising about 23% of all the named marine organisms. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat, as numerous groups are freshwater mollusc, freshwater and even terrestrial molluscs, terrestrial species. The phylum is typically divided into 7 or 8 taxonomy (biology), taxonomic class (biology), classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurobiology, neurologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodites
A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many taxonomic groups of animals, primarily invertebrates, are hermaphrodites, capable of producing viable gametes of both sexes. In the great majority of tunicates, mollusks, and earthworms, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. Hermaphroditism is also found in some fish species, but is rare in other vertebrate groups. Most hermaphroditic species exhibit some degree of self-fertilization. The distribution of self-fertilization rates among animals is similar to that of plants, suggesting that similar pressures are operating to direct the evolution of selfing in animals and plants. A rough estimate of the number of hermaphroditic animal species is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunicate
Tunicates are marine invertebrates belonging to the subphylum Tunicata ( ). This grouping is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time called Urochordata, and the term urochordates is still sometimes used for these animals. Despite their simple appearance and very different adult form, their close relationship to the vertebrates is certain. Both groups are chordates, as evidenced by the fact that during their mobile larval stage, tunicates possess a notochord, a hollow dorsal nerve cord, pharyngeal slits, post-anal tail, and an endostyle. They resemble a tadpole. Tunicates are the only chordates that have lost their Myomere, myomeric segmentation, with the possible exception of the seriation of the gill slits. However, Doliolida, doliolids still display segmentation of the muscle bands. Some tunicates live as solitary individuals, but others replicate by budding and be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
