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Harpoceratinae
Harpoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had involute and compressed shells with strong keels. Keel might be rarely missing, but this is considered to be an abnormality. This has been observed both in ''Cleviceras'' and '' Harpoceras'' and called as genus '' Monestieria'', which is now known to be invalid (into this invalid genus were added also abnormal unkeeled specimens of genus '' Protogrammoceras''). Another example is '' Pseudolioceras'', whose unkeeled specimen was used as type for description of invalid genus '' Praehaploceras''. Oxyconic forms of this subfamily ('' Polyplectus'' and '' Sphenarpites'') does not have any keel. Ribs were single, but in some genera also bifurcating with shapes from sigmoidal to falcate. Sometimes, shell can have only striate ribs or is smooth (''Sphenarpites'' and older specimens of '' Eleganticeras'' and '' Ovaticeras''). Tubercules are rare. Dimorphism is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hildoceratidae
Hildoceratidae is a family of ammonoid cephalopods from the Lower Jurassic, lower Pliensbachian (''Jamesoni'' zone) to lower Bajocian (maybe even upper Bajocian) substages, generally with strongly ribbed, involute shells. They are combined with the Hammatoceratidae (= Phymatoceratidae), Graphoceratidae, and Sonniniidae to make up the Hildoceratoidea. As many as seven subfamilies have been included in late 20th century, principle being the Arieticeratinae, Harpocertinae, Hildoceratinae, to which the Treatise, Part L, adds the Bouleiceratinae, Grammoceratinae, and Tmetoceratinae. Donovan et al. (1981) includes the same and adds the Leioceratinae which the older Treatise includes in the Graphoceratidae. Currently Leioceratinae are again members of Graphoceratidae and into Hildoceratidae are added newly established subfamily Leukadiellinae and Protogrammoceratinae, which has been by Donovan et al. (1981) considered as part of Harpoceratinae.M. K. Howarth 2013. Treatise on Inverte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Praepolyplectus
''Praepolyplectus'' is an extinct genus of cephalopod belonging to the family Hildoceratidae. It is sometimes considered to be a synonym of '' Polyplectus''. While it is currently not known from which species it has evolved, there are multiple theories about its origin. Formerly has been suggested, that it has evolved from Harpoceratinae Harpoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had involute and compressed shells with strong keels. Keel might be rarely missing, but this is considered to be an abnormal ..., but possible predecessor can be also in genus '' Protogrammoceras''. Perharps it can be ''Protogrammoceras meneghinii''. Its fossils were found in Italy, Spain and Morocco. This genus is very similar to ''Polyplectus'', but it is more evolute and has less acute ventral area. Sutures has shorter ventral lobe and other lobes are less developed and also less numerous when approaching umbilical region ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taffertia Taffertensis
''Taffertia'' is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age in the Falciferum zone and possibly only in Exaratum subzone. Its fossils were found in Canada, Morocco, Algeria and ItalyMOUTERDE, R.; ELMI, S. Caracteres differentiels des faunes d'Ammonites du Toarcien des bordures de la Tethys; signification paleogeographique. Bulletin de la Société géologique de France, 1991, 162.6: 1185-1195. Description Moderately involute, keeled, tectiform, sub-ogival shell with bold, regularly bifurcating ribs. It is similar to '' Pseudolioceras'', but is more evolute and differs from other ''Harpoceratinae Harpoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had involute and compressed shells with strong keels. Keel might be rarely missing, but this is considered to be an abnormal ...'' by having bifurcating ribs.J. Gu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neolioceratoides
Neolioceratoides is genus of ammonites that lived during the Pliensbachian and Toarcian stages of early Jurassic. It has been considered to be a synonym of '' Lioceratoides'',M. K. Howarth 2013. Treatise on Invertebrate Paleontology, Part L, Revised, Volume 3B, Chapter 4: Psiloceratoidea, Eoderoceratoidea, Hildoceratoidea.Schlegelmilch, R. (2014). Die Ammoniten des süddeutschen Lias: ein Bestimmungsbuch für Fossiliensammler und Geologen. Springer-Verlag. but cladistic analysis has shown, that this genus is not only valid, but they even belong to different subfamily, as ''Lioceratoides'' belongs to Harpoceratinae Harpoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had involute and compressed shells with strong keels. Keel might be rarely missing, but this is considered to be an abnormal ....Bardin, J., Rouget, I., & Cecca, F. (2016). The phylogeny of Hildoceratidae (Cephalopoda, Ammonitida) resolved by an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taffertia
''Taffertia'' is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age in the Falciferum zone and possibly only in Exaratum subzone. Its fossils were found in Canada, Morocco, Algeria and ItalyMOUTERDE, R.; ELMI, S. Caracteres differentiels des faunes d'Ammonites du Toarcien des bordures de la Tethys; signification paleogeographique. Bulletin de la Société géologique de France, 1991, 162.6: 1185-1195. Description Moderately involute, keeled, tectiform, sub-ogival shell with bold, regularly bifurcating ribs. It is similar to '' Pseudolioceras'', but is more evolute and differs from other ''Harpoceratinae Harpoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had involute and compressed shells with strong keels. Keel might be rarely missing, but this is considered to be an abnormal ...'' by having bifurcating ribs.J. Gu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osperleioceras
''Osperleioceras'' is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian stage. Its fossils were found in Europe and South America. First species of this genus, ''Osperleioceras bicarinatum'' has evolved in what is now France from ''Harpoceras subplanatum ''Harpoceras'' is an extinct genus of ammonite belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during the Toarcian age from the Falciferum zone to the Commune subzone of the Bifrons zone.Sepkoski, JacSepk ...''.M. K. Howarth 1992. HILDOCERATIDAE IN THE LOWER JURASSIC OF BRITAIN Description Genus is similar to ''Harpoceras'', but it is more involute and its whorl section is more triangular. Greatest width is near umbilicus. Flat whorl sides are converging to a flat narrow venter. It has strong keel, but there might be also slight ventro-lateral keels. Falcoid ribs are strongly projecting near venter. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubercle
In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to. In the case of certain orchids and cacti, it denotes a round nodule, small eminence, or warty outgrowth found on the lip. They are also known as podaria (singular ''podarium''). When referring to some members of the pea family, it is used to refer to the wart-like excrescences that are found on the roots. In fungi In mycology, a tubercle is used to refer to a mass of hyphae from which a mushroom is made. In animals When it is used in relation to certain dorid nudibranchs such as '' Peltodoris nobilis'', it means the nodules on the dorsum of the animal. The tubercles in nudibranchs can present themselves in different ways: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuciniceras
''Fuciniceras'' is an extinct cephalopod genus included in the ammonoid family Hildoceratidae, (order Ammonitida), that lived during the Pliensbachian The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 190.8 ± 1.5 Ma and 182.7 ± 1.5 Ma (million years ago). The ... stage of the Early Jurassic. The shell of ''Fuciniceras'' is generally small, evlute, and strongly ribbed. References ;Notes ;Bibliography *Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Geological Society of America and University of Kansas Press, 1957. Ammonitida genera Hildoceratidae Early Jurassic ammonites Ammonites of Europe {{jurassic-animal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hildoceratinae
Hildoceratinae is an extinct subfamily of cephalopods belonging to the family Hildoceratidae. Ammonites of this subfamily had shells with elliptical or quadrate whorl section with keel or tricarinate, bisulcate venter. Ribs were variable, from falcate to strongly angled and from fine to strong. They can be interrupted by spiral groove in midlateral part of the shell. While some species can be smooth, strongly ribbed ones can have tubercules. Microconchs have short lapplets that is in its shape similar to the shape of growth lines in spiral midlateral groove. Genera Bardin, J., Rouget, I., & Cecca, F. (2016). The phylogeny of Hildoceratidae (Cephalopoda, Ammonitida) resolved by an integrated coding scheme of the conch. Cladistics. * ''Hildaites'' Buckman, 1921 * ''Orthildaites'' Buckman, 1923 * '' Cingolites'' Sassaroli et Venturi, 2010 * ''Hildoceras'' Hyatt, 1867 * '' Urkutites'' Géczy, 1967 * ''Parahildaites'' Blaison, 1967 * ''Mercaticeras'' Buckman, 1913 * '' Hildaitoides'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
