Related Research Articles
Euhoplites is an extinct ammonoid cephalopod from the Lower Cretaceous, characterized by strongly ribbed, more or less evolute, compressed to inflated shells with flat or concave ribs, typically with a deep narrow groove running down the middle. In some, ribs seem to zigzag between umbilical tubercles and parallel ventrolateral clavi. In others the ribs are flexuous and curve forward from the umbilical shoulder and lap onto either side of the venter.
Acanthohoplites is an extinct genus of ammonites in the family Parahoplitidae that lived in the Aptian and Early Albian stages of the Early Cretaceous.
Aconeceras is an early Cretaceous ammonite included in the oppeliid subfamily Aconeceratidae, characterized by an involute, high-whorled, flat-sided shell that bears a finely serrate keel along the venter. Sutures have narrower and deeper elements than in Protaconeceras. Aconeceras has been found in western Europe, South Africa, and eastern Australia. Its stratigraphic range is from the Upper Barramian to the Lower Albian.
Anahoplites is a genus of rather involute, compressed hoplitid ammonites with flat sides, narrow flat or grooved venters, and flexious ribs or striae arising from weak umbilicle tubercles that end in fine dense ventrolateral nodes. The elements of their sutures are short, wide and jaggedy. Specimens of Annahoplites have diameters typically in the range of 4–6 centimetres (1.6–2.4 in) although some with diameters of as much as 19 centimetres (7.5 in) have been reported. The genus lived during the Cretaceous, from the Middle to the late Albian.
Barroisiceras is an acanthoceratacean ammonite from the Upper Cretaceous, Coniacian, included in the family Collignoniceratidae.
Coilopoceratidae is a family of generally large, proper ammonites with strongly involute shells from the Cretaceous, Albian to Turonian. Coilopoceratids have variably compressed shells with flattish to broadly rounded sides and narrowly rounded to sharp keel-like venters. Whorl sections are generally lanceolate. The suture is ammonitic with an overall clumpy appearance.
Beudanticeras is an extinct cephalopod genus from the Late Cretaceous period; Albian and Cenomanian, belonging to the ammonoid subclass and included in the family Desmoceratidae.
Hoplites is a genus of ammonite that lived from the Early Albian to the beginning of the Middle Albian. Its fossils have been found in Europe, Transcaspia and Mexico. Shell has compressed, rectangular till depressed and trapezoidal whorl section. There are strong umbilical bullae from which, prominent ribs are branching and these are interrupted on venter. Ends of ribs on the venter are prominent and can be both alternate or opposite. Some species have zigzagging ribs and these ribs ends usually thickened, or they can be raised into ventrolateral tubercles. These tubercles are mostly oblique clavi.
Collignociceras is a strongly ribbed and tuberculate, evolute ammonite from the Turonian of the western U.S. and Europe belonging to the ammonitid family Collignoniceratidae. The genus is named after the French paleontologist Maurice Collignon. The type is Collignoniceras woollgari, named by Mantell in 1822 for specimens from Sussex, England.
Forresteria is an extinct genus of cephalopod belonging to the subclass Ammonoidea. They flourished during the late Turonian and early Santonian of the Late Cretaceous, and were global in extent. Forresteria alluaudi and Forresteria hobsoni are considered marker fossils for the lower Coniacian in the American West.
Callihoplites is a genus of rather evolute ammonites from the Lower Cretaceous, Late Albian. Its whorl section squarish or compressed, inner whorls bearing umbilical bullae and ventrolateral clavi, with or without looped ribs between. The body chamber is smooth with a rounded venter.
Brancoceras is a rather small, strongly ribbed, acanthoceratacean ammonite from the Albian stage of the Lower Cretaceous, the shell evolute with a subquadrate whorl section and rounded venter. The suture forms a finely squiggly line with well-defined lobes and saddles. Brancoceras (Eubrancoceras) aegoceratoides reached a diameter of at least 4.2 centimetres (1.7 in).
Brancoceratidae is a family of acanthoceratoid ammonites from the middle of the Cretaceous, recognized by their commonly evolute shells with round, oval, or quadrate whorls, strong ribs, usual ventral keels, and at least, umblical tubercles. The family is thought to be derived from the Desmoceratidae (Desmoceratoidea), perhaps from Silesitoides or some allied genus.
Mantelliceras is an extinct ammonoid cephalopod genus belonging to the family Acanthoceratidae and type for the subfamily Mantelliceratinae, that lived from the Late Albian to the late Cenomanian stage of the Late Cretaceous.
Leymeriellidae is an extinct family of Lower Cretaceous ammonites comprising rather small forms distinguished from Hoplitidae by their flattened and grooved ribs and virtual absence of umbilical tubercles. The family is derived from the Desmoceratidae. Leymeriella schrammeni anterior has evolved from Desmoceras keilhacki keilhacki.
Pseudohaploceras is a genus of desmosceratid ammonites from the Early Cretaceous; Valanginian to Albian epochs.
Puzosia is a genus of desmoceratid ammonites, and the type genus for the Puzosiinae, which lived during the middle part of the Cretaceous, from early Aptian to Maastrichtian. Sepkoski defines the range from Albian to Santonian. The generic name comes from the Serbian words "Puž" (snail) and "oce/ose" (axis), gaining its name from the shell's snail-like appearance.
Melchiorites is a desmoceratid ammonite genus included in the subfamily Puzosiinae. Member species are characterized by an essentially evolute shell in which the early whorls are smooth, with sinuous radial or oblique constrictions but in which later whorls have feeble intermediate ribs on the outer part of the sides and venter.
Neocardioceras is a genus of evolute acanthoceratid ammonites from the uppermost Cenomanian, Upper Cretaceous, of Europe, western U.S. and Brazil.
Bredyia is a genus of ammonites from the lower part of the Middle Jurassic, found in Europe and North America.
References
- Arkell et al, Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Geol Soc of Amer. and Univ Kans press. 1957
- Ryszard Marcinowski and Jost Wiedmann. The Albian Ammonites of Poland. Palaeontologia Polonica no. 50, 1990
- Description of Dipoloceras
see also illustrations of
Dipoloceras cristatum , Archived 2009-09-11 at the Wayback Machine
 | This Ammonitina-related article is a stub. You can help Wikipedia by expanding it. |