|
Coreospiridae
Coreospiridae is an extinct family of Paleozoic molluscs of uncertain position taxonomically. They might be snails (Gastropoda), Helcionelloida, or they might be Monoplacophora. 2005 taxonomy The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005Bouchet 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=78278 categorizes Coreospiridae in the superfamily Scenelloidea within the Paleozoic molluscs of uncertain systematic position. 2006–2007 taxonomy According to P. Yu. Parkhaev, the family Coreospiridae is in the family Helcionelloidea ( Wenz, 1938) in the order Helcionelliformes (Golikov & Starobogatov, 1975) within the subclass Archaeobranchia (Parkhaev, 2001) in the class Helcionelloida (Peel, 1991). Genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latouchella
''Latouchella'' is an extinct genus of marine invertebrate animal, that is considered to be a mollusk and which may be a sea snail, a gastropod. It is a helcionellid from the Tommotian epoch of what is now Siberia. Its tightly coiled, spiral shell contains a number of low "walls" running up the front surface of the interior; these would have directed water currents within its shell. Between these walls are a series of furrows, parallel to the shell's aperture, giving casts of the internal structure the appearance of a railway line, with sleepers (created by furrows) tying together paired rails that run towards the apex of the shell. It was named by Edgar Sterling Cobbold in 1921 for the Rev. William Martin Digues La Touche of Wistanstow, Shropshire, England, in whose collection it was found. Description This genus had a curved, segmented shell, and it is often reconstructed as a snail-like creature. Older taxonomy The taxonomy of the genus ''Latouchella'' was originally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helcionelloidea
Helcionellid or Helcionelliformes is an order of small fossil shells that are universally interpreted as molluscs, though no sources spell out why this taxonomic interpretation is preferred. These animals are first found about in the late Nemakit-Daldynian age, which is the earliest part of the Cambrian period. A single species persisted to the Early Ordovician. These fossils are component of the small shelly fossils (SSF) assemblages. These are thought to be early molluscs with rather snail-like shells, although they lack any compelling molluscan synapomorphies and thus may not belong to the group. They have been alleged to represent ancestors of the modern conchiferans, a group that includes all the well-known modern classes – gastropods, cephalopods and bivalves. They have also been considered to represent direct ancestors to the cephalopods. Parkhaev (2006, 2007) considers these animals to be crown-group gastropods. Previous to the 2006 classification by Parkhaev, helcio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helcionelloida
Helcionelloida is an extinct group of ancient molluscs (phylum Mollusca). These are the oldest known conchiferan molluscs, that is, they had a mineralised shell. Some members of this class were mistaken for Monoplacophorans. The class was erected by Peel in 1991. Anatomy These animals were torsion (gastropod), untorted and they had a coiled, cone-shaped shell. The majority of species were small (shells being about two millimeters in length and or diameter). Modern reconstructions depict them as resembling snails. The shells of some genera, particularly ''Yochelcionella'', also possessed a "Snorkel (anatomy), snorkel"-like opening which was most likely used for breathing. 2005 taxonomy The Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), taxonomy of the Gastropoda by Bouchet & Rocroi, 2005Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scenelloidea
Scenelloidea is an extinct superfamily of paleozoic molluscs of uncertain position (Gastropoda, Helcionelloida, or Monoplacophora). Families Based on the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) families in the Scenelloidea include: * † Scenellidae ''Scenella'' is an extinct genus of fossil invertebrate animal which is generally considered to be a mollusc; at various times it has been suggested that this genus belongs with the gastropods, the monoplacophorans, or the helcionellids, although ... * † Coreospiridae * † Igarkiellidae References * Miller, S. A. (1889). ''North American Geology and Palaeontology for the use of Amateurs, Students and Scientists''. Western Methodist Book Concern. Cincinnati. 664 p Prehistoric gastropods Mollusc superfamilies {{paleo-gastropod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helcionelliformes
Helcionellid or Helcionelliformes is an order of small fossil shells that are universally interpreted as molluscs, though no sources spell out why this taxonomic interpretation is preferred. These animals are first found about in the late Nemakit-Daldynian age, which is the earliest part of the Cambrian period. A single species persisted to the Early Ordovician. These fossils are component of the small shelly fossils (SSF) assemblages. These are thought to be early molluscs with rather snail-like shells, although they lack any compelling molluscan synapomorphies and thus may not belong to the group. They have been alleged to represent ancestors of the modern conchiferans, a group that includes all the well-known modern classes – gastropods, cephalopods and bivalves. They have also been considered to represent direct ancestors to the cephalopods. Parkhaev (2006, 2007) considers these animals to be crown-group gastropods. Previous to the 2006 classification by Parkhaev, helcio ... [...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] |
Cambrian
The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 486.85 Ma. Most of the continents lay in the southern hemisphere surrounded by the vast Panthalassa Ocean. The assembly of Gondwana during the Ediacaran and early Cambrian led to the development of new convergent plate boundaries and continental-margin arc magmatism along its margins that helped drive up global temperatures. Laurentia lay across the equator, separated from Gondwana by the opening Iapetus Ocean. The Cambrian marked a profound change in life on Earth; prior to the Period, the majority of living organisms were small, unicellular and poorly preserved. Complex, multicellular organisms gradually became more common during the Ediacaran, but it was not until the Cambrian that fossil diversity seems to rapidly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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-bearing type of a nominal family-group taxon is a nominal genus called the 'type genus'; the family-group name is based upon that of the type genus." Any family-group name must have a type genus (and any genus-group name must have a type species, but any species-group name may, but need not, have one or more type specimens). The type genus for a family-group name is also the genus that provided the stem to which was added the ending -idae (for families). :Example: The family name Formicidae has as its type genus the genus ''Formica'' Linnaeus, 1758. Botanical nomenclature In botanical nomenclature, the phrase "type genus" is used, unofficially, as a term of convenience. In the '' ICN'' this phrase has no status. The code uses type specimens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
