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Radstockiceras

Radstockiceras is an extinct genus of lower Jurassic ammonite that lived from Oxynotum zone of upper Sinemurian to Raricostatum zone of lower Pliensbachian. Shells of these animals were oxycone and involute with umbilicus that took maximum of 12% ...

Tiltoniceras

Tiltoniceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, from upper Pliensbachian age, Spinatum zone until lower Toarcian, Tenuicostatum zone in what is now Europe, N ...

Uptonia

Uptonia is an extinct ammonite from the Lower Jurassic thats included in the eoderoceratoidean family Polymorphitidae. The shell of Uptonia is evolute with rounded simple ribs that form strong chevrons as they cross the Venter on the outer rim, a ...

Lytoceratidae

Lytoceratidae is a taxonomic family of ammonoid cephalopods belonging to the suborder Lytoceratina, characterized by very evolute shells that generally enlarge rapidly, having whorls in contact but mostly overlapping very sightly, or not at all. ...

Lytoceratinae

They are characterized by shells in which the whorls bear growth lines or lamellar folds, or both, commonly corresponding to constrictions in the internal mold. The external suture, that not lying against the previous whorl, has two lateral lobes ...

Earwig

Earwigs make up the insect order Dermaptera. With about 2.000 species in 12 families, they are one of the smaller insect orders. Earwigs have characteristic cerci, a pair of forceps-like pincers on their abdomen, and membranous wings folded under ...

Psiloceratidae

The Psiloceratidae are evolute, smooth or with blunt primary ribbing. The venter is rounded and generally smooth, in some feebly keeled. Sutures are simple with phylloid saddle endings in some. The aptychus is single, found in sutu in Psiloceras

Westbury Formation

The Westbury Formation is a geological formation in England, one of the Penarth Group. It dates back to the Rhaetian. The formation is named after the village of Westbury-on-Severn in Gloucestershire.

Fournierella

Fournierella is a member of the Muniericeratidae, a family of Upper Cretaceous ammonites characterized by moderately evolute shells with strong sinuous ribs that have tubercles on the shoulders and umbilical edge, and a more or less fastigate cro ...

Mediochoerus

Mediochoerus is an extinct genus of oreodont of the family Merycoidodontidae, subfamily Merycoidodontinae, endemic to North America during the Early Miocene-Middle Miocene subepochs, existing for approximately 7 million years.

Bustard

Bustards, including floricans and korhaans, are large, terrestrial birds living mainly in dry grassland areas and on the steppes of the Old World. They range in length from 40 to 150 cm. They make up the family Otididae. Bustards are omnivorous a ...

Geronticus

The small bird genus Geronticus belongs to the ibis subfamily. Its name is derived from the Greek gerontos in reference to the bald head of these dark-plumaged birds, in English they are called bald ibises. The genus was erected by the German nat ...

Laventan

The Laventan age is a period of geologic time within the Middle Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Colloncuran and precedes the Mayoan age.

Echioceratidae

Ammonites belonging to this family had serpenticone shells with keel, that can be surrounded by grooves, if a species is densely ribbed and compressed. Whorl section is circular, or has flat sides. Ribs are simple and strong with the exception of ...

Arietites

Arietites is a genus of massive, giant evolute, psiloceratacean ammonites in the family Arietitidae in which whorls are subquadrate and transversely ribbed and low keels in triplicate, separated by a pair of longitudinal grooves, run along the ve ...

Asteroceras

Asteroceras is an extinct genus of cephalopod belonging to the Ammonite subclass. These fast-moving nektonic carnivores lived during the Triassic and Jurassic periods.

Cheltonia

Cheltonia is an extinct genus of ammonite from the Upper Sinemurian substage of Lower Jurassic of Europe, Africa, and America. It is probably a microconch of genus Oxynoticeras.

Coroniceras

Coroniceras is a genus in the Arietitidae, a family in the ammonitid superfamily Psiloceratoidea, from the lower Sinermurian stage in the Lower Jurassic. It is a sub zone ammonite of the Arnioceras semicostatum Zone Coroniceras has a thin discoid ...

Dasyceras

Dasyceras is an early phylloceratid from the Sinemurian stage of the lower Jurassic, found in Europe. The shell is evolute, compressed in section. Smooth inner whorls, outer whorl develops Mature rough falcoid ribs that arise near the umbilical r ...

Echioceras

Shell of Echioceras species can reach a diameter of about 4–6 centimetres 1.6–2.4 in. The narrow and broad evolute shell is reinforced by fine ribs on inner whorls, progressively becoming stronger, straight and distinct.

Oxynoticeras

Oxynoticeras is an extinct genus of ammonite from the Early Jurassic of Europe and North America. This genus is characterized by its smooth shell, with almost invisible undulations on the flank, and a sharp keel. Synonym Oxynotoceras was establis ...

Paracymbites

Paracymbites is an extinct genus of lower Jurassic ammonite that lived during Raricostatum zone of upper Sinemurian. Animals belonging to this genus had small shells with semicircular whorl section and rounded or fastigate venter, of which umbili ...

Paroxynoticeras

Paroxynoticeras is an extinct genus of lower Jurassic ammonite that lived during upper Sinemurian. Animals belonging to this genus had platyconic shells with compressed whorl section and could grow to large sizes. In the case of young specimens, ...

Slatterites

Slatterites is an extinct genus of lower Jurassic ammonite that lived during upper Sinemurian. Animals belonging to this genus had small shells that had oxycone whorl section and sharp venter when young. In the case of older specimens, whorl sect ...

Xipheroceras

Xipheroceras is a Lower Jurassic ammonite belonging to the Eoderoceratidae, and sometimes placed in the subfamily Xipheroceratinae for which it is the namesake. It has been found in the upper Sinemurian of Europe and possibly Borneo. Xipheroceras ...

Coelognathosuchia

Coelognathosuchia is an extinct clade of neosuchian crocodyliforms that includes Goniopholididae and Pholidosauridae, two families of superficially crocodile-like aquatic crocodyliforms from the Mesozoic. Martin et al. named the clade after findi ...

Goniopholididae

Goniopholididae is an extinct family of moderate-sized semi-aquatic crocodyliforms superficially similar to living crocodiles. They lived between the Early Jurassic and the Late Cretaceous.

Aulacosphinctes

Aulacosphinctes is an extinct genus of ammonoid cephalopod that lived during the Late Jurassic and had a widespread distribution. Shell compressed, covered with strong, distinct, widely split edges, some simple, no tubercles on the Venter marked ...

Aulacostephanus

Aulacostephanus is an extinct ammonoid cephalopod genus from the Upper Jurassic Tithonian belonging to the perisphinctacean family Aulacostephanidae. Aulacostephanus produced discoidal, strongly ribbed, evolute shell of medium size, reaching a di ...

Behemoth (ammonite)

Behemoth is an extinct ammonite cephalopod genus within the family Dorsoplanitidae, that lived during the upper Tithonian stage of Late Jurassic Europe and Greenland.

Bihenduloceras

Bihenduloceras is an Upper Jurassic perisphinctacean ammonite and member of the olcostephanid subfamily Spiticeratine. Its shell has a subquadrate whorl section, flattended venter, and fine ribs that spring in bundles from large umbilical tubercles.

Glottoptychinites

The shell, which grew to be rather large, is evolute, strongly and sharply ribbed. Ribbing is both simple and biplicate, with primary ribs bifurcating on either flank before crossing the venter. The whorl section is round. Glottoptychinites in a ...

Hemilytoceras

Hemilytoceras is a lytoceratin ammonite genus with round inner whorls, outer whorls becoming depressed and in some developing high lamellae that bend forward over the venter. The type species H. immanae came from the Tithonian of Europe. The genu ...

Pectinatites

Pectinatites is an extinct cephalopod genus belonging to the order Ammonoidea, that lived during the upper Tithonian stage of the Late Jurassic. They were fast-moving nektonic carnivores. Clutches of eggs attributed to this genus have been discov ...

Nodicoeloceratinae

The subfamily Nodicoeloceratinae comprises early Jurassic ammonite genera that lived during early to middle Toarcian stage. Origin of this subfamily is unknown, but first genus Nodicoeloceras has evolved from Dactylioceras or Kedonoceras.

Asapholytoceras

Asapholytoceras is a lytoceratid ammonite, originally from the upper Lower Jurassic of southeastern Europe with high, compressed whorls and a sharp angle to the umbilical shoulder. The exposed suture has four primary lobes on either side, the int ...

Catacoeloceras

Catacoeloceras is genus of ammonite that lived during middle to late Toarcian stage of early Jurassic. Members of this genus existed from Crassum Subzone of Bifrons Zone to Variabilis Zone. Their fossils were found in Europe, northern Africa, Asi ...

Cleviceras

Cleviceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian and possibly even uppermost Pliensbachian age. Sometimes, it is considered to be a synonym of E ...

Collina (ammonite)

Collina is genus of ammonite that lived during lower to upper Toarcian stage of early Jurassic. Members of this genus existed from Braunianus Subzone to Variabilis Zone. Their fossils were found in Europe, Asia, North America and South America. I ...

Grammoceras

Grammoceras is an extinct genus of ammonite found in Yorks Ravenscar, England, from Jurassic period sediments. Its overall distribution is fairly worldwide. Grammoceras is a thin, discoidally evolute shell with a simple, gently sigmoid ribbing an ...

Hammatoceras

Hammatoceras is a genus of ammonites belonging to the family Hammatoceratidae which lived during the Late Toarcian stage of the Early/Lower Jurassic between about 184 and 175 million year ago.

Mesodactylites

Mesodactylites, which is sometimes considered to be a synonym of Nodicoeloceras is genus of ammonite that lived during early to middle Toarcian stage of early Jurassic. Their fossils were found in southern and central Europe and northern Africa. ...

Microdactylites

Microdactylites, which is sometimes considered to be a synonym of Dactylioceras, is genus of ammonite that lived during early to middle Toarcian stage of early Jurassic. Their fossils were found in England, France, Italy, Germany and Hungary. Spe ...

Mucrodactylites

Mucrodactylites, which is sometimes considered to be a synonym of Collina, is genus of ammonite that lived during middle to late Toarcian stage of early Jurassic. Their fossils were found in Europe, northern Africa and South America. Species belo ...

Nodicoeloceras

Nodicoeloceras is genus of ammonite that lived during early to middle Toarcian stage of early Jurassic. Members of this genus existed from Exaratum Subzone of Falciferum Zone to Commune subzone of Bifrons Zone. Their fossils were found in Europe, ...

Orthildaites

Orthildaites is genus of ammonites that lived during the lower Toarcian stage of early Jurassic, during Falciferum subzone. Shell of these ammonites had quadrate whorl section with broad venter and strong keel in the center. Almost stright ribs w ...

Parahildaites

Parahildaites is genus of ammonites that lived during the lower Toarcian stage of early Jurassic, during Bifrons zone. It differs from Hildaites and Hildoceras by having smooth shell after reaching 4 cm in diameter. There is no spiral groove and ...

Peronoceras

Peronoceras is genus of ammonite that lived during the middle Toarcian stage of early Jurassic. Members of this genus existed only in Fibulatum Subzone of Bifrons Zone. Their fossils were found in Europe, northern Africa, Asia, North America and ...

Porpoceras

Porpoceras is genus of ammonite that lived during the early and middle Toarcian stage of early Jurassic. Members of this genus existed from uppermost part of Serpentinum Zone to Variabilis Subzone. Their fossils were found in Europe, Asia, North ...

Ptycholytoceras

Ptycholytoceras is a genus of fast-moving nektonic ammonoid carnivores included in the Lytoceratinae in which the shell has round inner and depressed outer whorls and sides with dorso-ventrally sloping folds that do not pass onto the venter. View ...