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Bellerophontidae
The Bellerophontidae are an extinct family of specialized globose bellerophontids, Paleozoic and early Triassic mollusks of the class Gastropoda. Geological range These mollusks appeared in the Late Cambrian and continued until the Early Triassic. Shell description The shell resembles a miniature ''Nautilus'', with greatly overlapping, rounded whorls, in which the last whorl completely encompasses the others, leaving either a very narrow umbilicus on either side, or none at all. At the aperture of the shell is a slit, which results in a sort of low ridge that runs along the length of shell. The shell has a low profile and these possibly were active, fast-moving molluscs. Taxonomy 1960 taxonomy Knight ''et al.'' 1960 in the ''Treatise on Invertebrate Paleontology'' consider the Bellerophontidae a very large family made up of a number of subfamilies and tribes. The 1960 classification places the family Bellerophontidae in the order Bellerophontida Ulrich & Scofield, 1897. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bellerophontoidea
Bellerophontoidea, common name "bellerophonts",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=78278 is a superfamily of extinct planospirally-coiled globose molluscs. This superfamily is generally included within the Gastropoda, but may instead be a group of monoplacophorans. The taxon first appeared late in the Cambrian and continued until late in the Triassic. Biology Unlike normal gastropods, the shells of Bellerophonts are characterised by a completely planispiral pattern of coiling, such as one finds in shelled cephalopods. Experts disagree whether Bellerophontids should be classified as torted gastropods, or as untorted Tergomya, or whether the group Bellerophontida is perhaps an artificial constr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bellerophon (genus)
''Bellerophon'' is a genus of extinct paleozoic marine molluscs of uncertain position (Gastropoda or Monoplacophora) in the family Bellerophontidae. The genus was named after Bellerophon, the ancient Greek hero. ''Bellerophon'' is the type genus of the family Bellerophontidae. Shell description The genus is characterised by a shell which is globose, convolute, and planispiral (symmetrically coiled). The shell of ''Bellerophon'' superficially resembles that of a miniature cephalopod (e.g. ''Nautilus'' or an ammonite), except that septa are lacking. The shell of ''Bellerophon'' is often a couple of centimeters in maximum dimension. The external surface is smooth, ornamented only by growth lines. There is a low crest or ridge running along the midline of the shell. Many specimens of ''Bellerophon'' show something resembling a "waterline" about halfway up the shell, suggesting that a large amount of the mantle and foot were exposed and covered the outside of the shell, as in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bellerophontida
The Bellerophontida is a taxonomic order of extinct marine mollusks that are found in the fossil record from the Lower Cambrian to the Lower Triassic. They are considered by some experts to be primitive sea snails with primarily symmetrically coiled shells, marine gastropod mollusks. R.C Moore and J. Brooks Knight ''et al'' 1960 Treatise on Invertebrate Paleontology, Part I Mollusca 1 recognized bellerophonts as true gastropods, placing them as the suborder Bellerophontina in the subclass Prosobranchia, order Archaeogastropoda. Some more recent workers in the field have expressed uncertainty as to the taxonomic placement of this group. Shell morphology Shells of bellerophontids are most commonly isotrophic (coiled symmetrically), rarely slightly asymmetric. Most are closely coiled with some general more openly coiled, cyrtiform; predominantly with a median slit in the upper lip of the aperture, or with a series of openings known as tremata, usually generating a selenizone whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter J
Peter may refer to: People * List of people named Peter, a list of people and fictional characters with the given name * Peter (given name) ** Saint Peter (died 60s), apostle of Jesus, leader of the early Christian Church * Peter (surname), a surname (including a list of people with the name) Culture * Peter (actor) (born 1952), stage name Shinnosuke Ikehata, Japanese dancer and actor * ''Peter'' (album), a 1993 EP by Canadian band Eric's Trip * ''Peter'' (1934 film), a 1934 film directed by Henry Koster * ''Peter'' (2021 film), Marathi language film * "Peter" (''Fringe'' episode), an episode of the television series ''Fringe'' * ''Peter'' (novel), a 1908 book by Francis Hopkinson Smith * "Peter" (short story), an 1892 short story by Willa Cather Animals * Peter, the Lord's cat, cat at Lord's Cricket Ground in London * Peter (chief mouser), Chief Mouser between 1929 and 1946 * Peter II (cat), Chief Mouser between 1946 and 1947 * Peter III (cat), Chief Mouser between 1947 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoplacophora
Monoplacophora , meaning "bearing one plate", is a polyphyletic superclass of molluscs with a cap-like shell inhabiting deep sea environments . Extant representatives were not recognized as such until 1952; previously they were known only from the fossil record, and were thought to have become extinct 375 million years ago. Although the shell of many monoplacophorans is limpet-like in shape, they are not gastropods, nor do they have any close relation to gastropods. Definition Discussion about monoplacophorans is made difficult by the slippery definition of the taxon; some authors take it to refer to all non-gastropod mollusks with a single shell, or all single-shelled mollusks with serially repeated units; whereas other workers restrict the definition to cap-shaped forms, excluding spiral and other shapes of shell. The inclusion of the gastropod-like Bellerophontoidea within the group is also contentious. One attempt to resolve this confusion was to separate out the predom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
