Platyceras | |
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Platyceras pulcherrimum from the Logan Formation (Mississippian) of Wooster, Ohio) | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Family: | † Platyceratidae |
Genus: | † Platyceras Conrad, 1840 |
Synonyms | |
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Platyceras is a genus of extinct Paleozoic sea snails, marine gastropod mollusks in the family Platyceratidae. This genus is known from the Silurian to the Middle Triassic periods and especially abundant in the Devonian and Carboniferous. [1] It is the type genus of the family Platyceratidae.
Platyceras has a distinctive, curved conical shape that is easily recognized. The cap-like shell is high and broad anteriorly. The posterior portion of the shell, at the apex, is usually slightly coiled in an asymmetrical fashion. Frequently, the front portions of the shells are broken, though the posterior sections are relatively well preserved. Platyceras is particularly abundant in Devonian deposits (359 million to 416 million years old). [1] Platyceras and other platyceratid gastropods are known for the complex symbiotic relationships they had with crinoids. [2]
Fossils of Platyceras have been found all over the world, [1] among others in the Silurian Bertie Formation of Ontario and New York and the Devonian Floresta Formation of Boyacá, Colombia. [3]
Bothriolepis was a widespread, abundant and diverse genus of antiarch placoderms that lived during the Middle to Late Devonian period of the Paleozoic Era. Historically, Bothriolepis resided in an array of paleo-environments spread across every paleocontinent, including near shore marine and freshwater settings. Most species of Bothriolepis were characterized as relatively small, benthic, freshwater detritivores, averaging around 30 centimetres (12 in) in length. However, the largest species, B. rex, had an estimated bodylength of 170 centimetres (67 in). Although expansive with over 60 species found worldwide, comparatively Bothriolepis is not unusually more diverse than most modern bottom dwelling species around today.
Holoptychius is an extinct genus of porolepiform lobe-finned fish from the Middle Devonian to Carboniferous (Mississippian) periods. It is known from fossils worldwide. The genus was first described by Louis Agassiz in 1839.
Atrypa is a genus of brachiopod with round to short egg-shaped shells covered with many fine radial ridges. Growth lines form perpendicular to the costae and are spaced approximately 2 to 3 times further apart than the costae.. The pedunculate valve is slightly convex, but oftentimes levels out or becomes slightly concave toward the anterior margin. The brachial valve is highly convex. Neither valve contains an interarea. Atrypa had a large geographic range and occurred from the late Lower Silurian (Telychian) to the early Upper Devonian (Frasnian). Other sources expand the range from the Late Ordovician to Carboniferous, approximately from 449 to 336 Ma. A proposed new species, A. harrisi, was found in the trilobite-rich Floresta Formation in Boyacá, Colombia.
Anchiopsis is a genus of trilobite in the order Phacopida, which existed in what is now New York, U.S.A. It was described by Delo in 1935, and the type species is Anchiopsis anchiops, which was originally described as Calymene anchiops by Green in 1832.
Tarijactinoides is a genus of trilobites in the order Phacopida, which existed in what is now Bolivia. It was described by Suárez Soruco in 1971, and the type species is Tarijactinoides jarcasensis.
Platyceratidae is an extinct family of Paleozoic sea snails, marine gastropod mollusks. This family may belong in the Patellogastropoda or the Neritimorpha.
The Devonian Jeffersonville Limestone is a mapped bedrock unit in Indiana and Kentucky. It is highly fossiliferous. The Vernon Fork Member contains Volcanic ash associated with the Tioga Bentonites.
The Brassfield Formation, named by A.F. Foerste in 1906, is a limestone and dolomite formation exposed in Arkansas, Ohio, Kentucky, Indiana, Tennessee and West Virginia in the United States. It is Early Silurian in age and well known for its abundant echinoderms, corals and stromatoporoids. In Ohio, where the unit has escaped dolomitization, the Brassfield is an encrinite biosparite with numerous crinoid species.
The Chicamocha Canyon is a steep sided canyon carved by the Chicamocha River in Colombia. With a maximum depth of 2,000 metres (6,600 ft), an area of 108,000 hectares and a length of 227 kilometres (141 mi), the canyon is the second-largest worldwide. The canyon is situated in the departments of Boyacá and Santander, stretching from Soatá in the southeast to Girón and Betulia in the northwest.
Paleontology in Wisconsin refers to paleontological research occurring within or conducted by people from the U.S. state of Wisconsin. The state has fossils from the Precambrian, much of the Paleozoic, some a parts of the Mesozoic and the later part of the Cenozoic. Most of the Paleozoic rocks are marine in origin. Because of the thick blanket of Pleistocene glacial sediment that covers the rock strata in most of the state, Wisconsin’s fossil record is relatively sparse. In spite of this, certain Wisconsin paleontological occurrences provide exceptional insights concerning the history and diversity of life on Earth.
Trigonia is an extinct genus of saltwater clams, fossil marine bivalve mollusk in the family Trigoniidae. The fossil range of the genus spans the Paleozoic, Mesozoic and Paleocene of the Cenozoic, from 298 to 56 Ma.
The Montoya Group is a group of geologic formations in westernmost Texas and southern New Mexico. It preserves fossils dating back to the late Ordovician period.
Antarctilamna is an extinct genus of Devonian cartilaginous fish originally exemplified by Antarctilamna prisca from South Eastern Australia and Antarctica. The latest occurring described species is Antarctilamna ultima from the Waterloo Farm lagerstätte in South Africa. Antarctilamna has robust ctenacanthid-like spines which lack a deep insertion area, and are borne in front of the first dorsal fin; in addition to distinctive diplodont teeth with small intermediate cusps. Antarctilamna-like spines, known from the Bunga Beds locality in Australia have been ascribed to A. prisca.
Asterolepis is an extinct genus of antiarch placoderms from the Devonian of North and South America and Europe. They were heavily armored flat-headed benthic detritivores with distinctive jointed limb-like pectoral fins and hollow spine. The armor plate gives the Asterolepis a box-like shape. Its pectoral fins are also armored but the caudal and dorsal fin are not. The first fossils were named by M. Eichwald in 1840 after noticing star-like markings on the fossils.
The Floresta Formation is a geological formation of the Altiplano Cundiboyacense in the Eastern Ranges of the Colombian Andes. The sequence of siltstones, shales, coquinas and sandstone beds dates to the Devonian period; Late Emsian, Eifelian and Early Givetian epochs, and has a maximum thickness of 600 metres (2,000 ft). The unit is highly fossiliferous; brachiopods, bryozoans, gastropods, trilobites, corals and bivalves have been found in the Floresta Formation. Some fragments of Placoderm fish fossils were found in the Floresta Formation, while the overlying Cuche Formation is much richer in fish biodiversity.
The Soatá Formation is a geological formation of the northern Altiplano Cundiboyacense, Eastern Ranges of the Colombian Andes. The formation consists mainly of shales with conglomerates and dates to the Quaternary period; Late Pleistocene epoch. The heavily eroded formation has a maximum measured thickness of 30.8 metres (101 ft). It contains the lacustrine and fluvio-glacial sediments of elongated paleolake Soatá, that existed on the Altiplano in the valley of the Chicamocha River.
The Cuche Formation is a geological formation of the Floresta Massif, Altiplano Cundiboyacense in the Eastern Ranges of the Colombian Andes. The sequence of siltstones, shales, and sandstone beds dates to the Late Devonian and Early Carboniferous periods, and has a maximum thickness of 900 metres (3,000 ft).
The Río Cachirí Group is a geological group of the Cesar-Ranchería Basin, Colombia and the Serranía del Perijá of the northernmost Colombian and Venezuelan Andes. The group of shales, sandstones and limestones is of Devonian age and has a maximum thickness in the Venezuelan section of 2,438 metres (7,999 ft). The group contains abundant fauna; crinoids, bryozoa, brachiopods and molluscs have been found in the group.
The Girón Formation is an extensive geological formation stretching across 325 kilometres (202 mi) from the north in Teorama, Norte de Santander, across the Mesa de Los Santos and Chicamocha Canyon towards west of Nobsa, Boyacá in the northern part of the Altiplano Cundiboyacense in the south. The formation extends across the northern and central part of the Eastern Ranges of the Colombian Andes.