Biloclymenia | |
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Scientific classification ![]() | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | † Ammonoidea |
Order: | † Clymeniida |
Family: | † Biloclymeniidae |
Genus: | † Biloclymenia Schindewolf, 1923 |
Species [2] | |
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Biloclymenia is a genus in the ammonoid order Clymeniida which is characterized by a dorsal retrosiphonitic siphuncle with long adapically pointing septal necks.
The shell of shell Biloclymenia is thickly discoidal, more or less involute, with a moderately wide umbilicus, lightly thickened sides and rounded venter. The shell is surface smooth, covered merely by growth lines which form two salients. The ventral lobe of the suture is wide and divided in two with a secondary lobe at the top of median saddle. Additional sutural elements are two umbilical, an inner lateral and a dorsal lobe.
The Treatise on Invertebrate Paleontology (Part L 1957) includes Biloclymenia in the Wocklumariidae which is derived from Hexaclymeniidae. Saunders et al(1999) expands upon this theme and puts Bilocymenia and Biloclymeniidae in the Sellaclymeniaceae (suborder Gonioclymeniina), indicates the following phylogenetic progression beginning with Hexaclymenia. Hexaclymenia (Hexaclymeniidae) --> Uraloclymenia (Miroclymeniidae) --> Kiaclymenia (Biloclymeniidae) --> Bioloclymenia.
Agathiceras is a subglobose goniatitid from the family Agathiceratidae, widespread and locally abundant in Lower Pennsylvanian to Middle Permian sediments, e.g. the Urals, Sicily, and Texas.
Ammonoceratites is an extinct genus of ammonoid cephalopod known from the Albian of British Columbia, Madagascar, New Zealand, and Japan, included in the Lytoceratidae.
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 internal dorsal lobe is not cruciform.
Audaxlytoceras is an extinct genus of lytoceratid ammonites.
Arcestes is a genus of extinct ceratitid ammonites found in Triassic-aged marine strata.
Arcticoceras is an extinct ammonoid cephalopod genus from the late Middle Jurassic belonging to the ammonite family Cardioceratidae, more commonly found to high northern latitudes.
Baschkirites is an extinct cephalopod genus belonging to the ammonoid order Goniatitida that lived during the Early Carboniferous (Bashkirian).
Dobrogeites is a genus of ammonoids from the order Ceratitida, included in the family Megaphyllitidae that produced evolute compressed planispiral shells with rounded venters, inner whorls ornamented as in Tirolites, outer whorls smooth, suture with multiple smooth lobes; Initially found in Anisian sediments in Romania.
Thalassoceratidae a family of late Paleozoic ammonites included in the goniatitid superfamily Thalassoceratoidea along with the Bisatoceratidae. Some eight genera are included, although the specific number and exactly which depends on the particular classification.
Phaulostephanus is an extinct genus from the ammonoid family Stephanoceratidae, which is part of the ammonitid superfamily Stephanoceratoidea, that lived during the early Middle Jurassic.
Metrolytoceras is an extinct cephalopod genus that lived during the Middle Jurassic, characterized by a planispiral evolute shell with smooth middle and outer whorls, flat sides and simplified sutures.
Clymenia is a genus in the ammonoid order Clymeniida, restricted to the Upper Devonian, characterized as with all clymeniids by a dorsal siphuncle that runs along the inside of the whorls, unusual for ammonoids.
Bostrychoceras is a genus of heteromorph ammonite from the family Nostoceratidae. Fossils have been found in Late Cretaceous sediments in Europe and North America.
Gymnites is a genus of ammonoid cephalopod from the Middle Triassic belonging to the ceratitid family Gymnitidae. These nektonic carnivores lived during the Triassic period, Anisian age.
Craspedites is an ammonoid cephalopod included in the Perisphinctaceae that lived during the Late Jurassic and Early Cretaceous, found in Canada, Greenland, Poland, and the Russian Federation.
Pleuroacanthites is one of two genera included in the Early Jurassic Pleuroacanthitidae and sole representative of the subfamily Pleuroacanthitinae. The shell of Pleuroacanthites is very evolute, with numerous whorls subcircular in section becoming incipiently keeled in the adult. Early whorls have parabolic nodes, later whorls are covered with oblique line which form a long ventral sinus. Sutures have lytoceratid (moss-like) lobes but more or less phylloid saddle endings.
Lytoceratinae is a subfamily of ammonoid cephalopods that make up part of the family Lytoceratidae.
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.
Pronorites is a prolecanitid genus from the middle and upper Carboniferous, upper Mississippian and Pennsylvanian. Distribution is wide spread.
Dayiceras is a finely ribbed polymorphitid eoderoceratacean ammonoid cephalopod from the Jurassic, named by Spath in 1920. The shell is evolute, coiled such that all whorls are exposed. The whorl section is compressed such as to be higher than wide. A row of fine tubercles runs along the middle of the outer rim, the venter.