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Phacoceras
The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida Diagnosis The Centroceratidae, which range from the Middle Devonian to the Lower Permian, are characterized by gyroconic, evolute tarphyceraconic, and involute nautiliconic shells with compressed whorls, typically with a quadrangular whorl section in which the flanks converge on venter that is much narrower than the dorsum and ventral and umbilical shoulders are sharply angular, or rarely rounded. In some, e.g. ''Centroceras'', the flanks are divided by a ridge that runs along the middle. Sutures have ventral and lateral lobes but are transverse dorsally. The siphuncle is tubular and close to but not on in contact with the venter (Kummel 1964). Phylogeny and genera Evolutionary sequence The Centroceratidae are thought probably to be derived from the rutoceratid stock (Flower 1950, 1988, Kummel 1964) Earliest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phacoceras
The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida Diagnosis The Centroceratidae, which range from the Middle Devonian to the Lower Permian, are characterized by gyroconic, evolute tarphyceraconic, and involute nautiliconic shells with compressed whorls, typically with a quadrangular whorl section in which the flanks converge on venter that is much narrower than the dorsum and ventral and umbilical shoulders are sharply angular, or rarely rounded. In some, e.g. ''Centroceras'', the flanks are divided by a ridge that runs along the middle. Sutures have ventral and lateral lobes but are transverse dorsally. The siphuncle is tubular and close to but not on in contact with the venter (Kummel 1964). Phylogeny and genera Evolutionary sequence The Centroceratidae are thought probably to be derived from the rutoceratid stock (Flower 1950, 1988, Kummel 1964) Earliest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diorugoceras
The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida Diagnosis The Centroceratidae, which range from the Middle Devonian to the Lower Permian, are characterized by gyroconic, evolute tarphyceraconic, and involute nautiliconic shells with compressed whorls, typically with a quadrangular whorl section in which the flanks converge on venter that is much narrower than the dorsum and ventral and umbilical shoulders are sharply angular, or rarely rounded. In some, e.g. ''Centroceras'', the flanks are divided by a ridge that runs along the middle. Sutures have ventral and lateral lobes but are transverse dorsally. The siphuncle is tubular and close to but not on in contact with the venter (Kummel 1964). Phylogeny and genera Evolutionary sequence The Centroceratidae are thought probably to be derived from the rutoceratid stock (Flower 1950, 1988, Kummel 1964) Earliest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carlloceras
The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida Diagnosis The Centroceratidae, which range from the Middle Devonian to the Lower Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last ..., are characterized by gyroconic, evolute tarphyceraconic, and involute nautiliconic shells with compressed whorls, typically with a quadrangular whorl section in which the flanks converge on venter that is much narrower than the dorsum and ventral and umbilical shoulders are sharply angular, or rarely rounded. In some, e.g. ''Centroceras'', the flanks are divided by a ridge that runs along the middle. Sutures have ventral and lateral lobes but are transverse dorsally. The siph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strophiceras
''Strophiceras'' is an extinct genus of cephalopods from the Order Nautilida, which includes, in a separate family, ''Nautilus'' and ''Allonautilus''. ''Strophioceras'', a gyrogonic form that comes from the Middle Devonian of Europe and named by Hyatt in 1844 is part of the Trigonoceratacean family Centroceratidae which was extant from the Devonian to the Early Permian. ( 1954. Flower 1950) Description See also * Nautiloidea * Nautilida ** List of nautiloids References * Flower ''and Kummel'' 1950. A Classification of the Nautiloidea; Jour Paleontology, 24(5), 606–616, Nov 1950. * , B. 1964. Nautiloidea - Nautilida; Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ... Part K, Mollusca 3; R.C. Moore (ed), Univ. Kans. press. * Sepkoski, J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Nautiloid Families
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treatise On Invertebrate Paleontology
The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and extant (still living) invertebrate animals. The prehistoric invertebrates are described as to their taxonomy, morphology, paleoecology, stratigraphic and paleogeographic range. However, taxa with no fossil record whatsoever have just a very brief listing. Publication of the decades-long ''Treatise on Invertebrate Paleontology'' is a work-in-progress; and therefore it is not yet complete: For example, there is no volume yet published regarding the post-Paleozoic era caenogastropods (a molluscan group including the whelk and Common periwinkle, periwinkle). Furthermore, every so often, previously published volumes of the ''Treatise'' are revised. Evolution of the proje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centroceras (cephalopod)
Centroceras may refer to: * ''Centroceras'' (alga), a genus of red algae in the family Ceramiaceae * ''Centroceras'' (cephalopod) Hyatt, 1884, a fossil genus of cephalopods in the family Centroceratidae * ''Centroceras'' Wedekind, 1908, a fossil genus of cephalopods in the family Cheiloceratidae Cheiloceratidae is a family of ammonoid cephalopods included in the goniatitid suborder Tornoceratina in which the suture has 4 to 12 lobes, the ventral one undivided and those in the lateral areas originating as subdivisions of internal and ex ..., synonym of '' Torleyoceras'' {{Genus disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homaloceras
''Homaloceras'' is an extinct nautiloid cephalopod from the Middle Devonian with a strongly curved shell, included in the nautilid family Centroceratidae. ''Homaloceras'' is characterized by a smooth, exogastrically curved and laterally compressed, cyrtoconic to gyroconic, shell with the ventral margin the outer rim. The venter is narrow and concave with a groove running down the middle; the dorsum on the inner rim, rounded; the sides broadly convex and convergent. The suture is only slightly sinuous, the siphuncle tubular and near the venter. ( 1964) ''Homaloceras'', named by Whiteavus in 1891, and found in North America, in Canada, is the most primitive and one of the earliest genera assigned to the Centroceratidae. ( 1964) The Nautiloidea, in which ''Homaloceras'' is included, is a subclass of once diverse and numerous shelled cephalopods characterized by a retrochoantic siphuncle in which the septal necks point back toward the apex. See also *List of nautiloids R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids ( reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rutoceratidae
Rutoceratidae is a family of prototypical nautilids, derived probably from either Brevicoceratidae or Acleistoceratidae of the order Oncocerida early in the Devonian. Rutoceratidae comprise a family within the oncocerid superfamily TainocerataceaeKummel 1964, Nautiloidea-Nautilida; Treatise on Invertebrate Paleontology, Part K: Nautiloidea, Teichert & Moore (eds) They are generally characterized by cyrtoconic and gyroconic shells, commonly with spines, nodes, or frills, although some included genera are almost orthoconic, and a commonly empty, tubular ventral siphuncle. The Rutocertids lived during the Devonian and Mississippian (early Carboniferous) and are the ancestral stock of Nautilida. Within the superfamily Taintocerataceae, rutoceratids gave rise to the exclusively Devonian family Tetragonoceratidae and near the start of the Mississippian to the family Koninckioceratidae which lasted into the Permian and to Tainoceratidae which lasted through most of the Triassic. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siphuncle
The siphuncle is a strand of tissue passing longitudinally through the shell of a cephalopod mollusk. Only cephalopods with chambered shells have siphuncles, such as the extinct ammonites and belemnites, and the living nautiluses, cuttlefish, and ''Spirula''. In the case of the cuttlefish, the siphuncle is indistinct and connects all the small chambers of that animal's highly modified shell; in the other cephalopods it is thread-like and passes through small openings in the septa (walls) dividing the camerae (chambers). Some older studies have used the term siphon for the siphuncle, though this naming convention is uncommon in modern studies to prevent confusion with a mollusc organ of the same name. Function The siphuncle is used primarily in emptying water from new chambers as the shell grows. To perform this task, the cephalopod increases the saltiness of the blood in the siphuncle, and the water moves from the more dilute chamber into the blood through osmosis. At the sam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
