Polonoceras

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Polonoceras
Temporal range: Famennian
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Goniatitida
Family: Tornoceratidae
Subfamily: Aulatornoceratinae
Genus:Polonoceras
Dybczynski, 1913
Species
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Polonoceras is a genus included in the goniatitid subfamily Aulatornoceratinae named by Dybczynski, 1913. The type species is Polonoceras planum Dybczynski. According to Miller, et al. in the American Treatise on Invertebrate Paleontology, 1957, Polonoceras is a subgenus of Tornoceras .

Aulatornoceratinae is one of three subfamilies of the gonititid family Tornoceratidae, an extinct order of Paleozoic ammonoid cephalopods. Aulotornoceratinae was established as a subfamily by R.T.Becker, 1993, initially for Aulatornoceras, named by Schindewolf, 1922. Subsequently four other genera have been added.

The Treatise on Invertebrate Paleontology published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and extant invertebrate animals. The prehistoric invertebrates are described as to their taxonomy, morphology, paleoecology, stratigraphic and paleogeographic range. However, genera with no fossil record whatsoever have just a very brief listing.

Tornoceras is a strongly involute, subdiscoidal Middle and Upper Devonian goniatite with a suture that forms six to ten lobes.

Polonoceras, which lived during the Late Devonian, has an involute or moderately evolute, discoidal shell with a high aperture and flattened, grooved venter. The adventitious lobe, next to the ventral lobe, is widely rounded, the Ventro-lateral saddle narrow and sometimes higher than lateral saddle.

Polonoceras is found in Europe, in Poland, where it was discovered. It is also reported from Upper Devonian (middle Famennian) in Canning Basin, Western Australia.

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<i>Goniatites</i> genus of molluscs (fossil)

Goniatites is a genus of extinct cephalopods belonging to the family Goniatitidae, included in the superfamily Goniatitaceae. Hibernicoceras and Hypergoniatites are among related genera.

Ussuria is a genus of Lower Triassic ammonites with a smooth, involute discoidal shell with submonophyllic sutures, belonging to the ceratitid family Ussuriidae.

Cheiloceratidae is a family of ammonoid cephalopods included in the goniatitid suborder Tornoceratina in which the suture has 4 to 12 lobes, the ventral one undivided and those in the lateral areas originating as subdivisions of internal and external lateral saddles.

The Posttornoceratidae are Late Devonian goniatites (Ammonoidea) included in the superfamily Tornoceratoidea. The family, Posttornoceratidae, named by Bogoslovsky in 1962, is based on the genus Posttornoceras, named by Wedekind in 1910, originally included in the Tornoceratidae.

Tornoceratidae is a family of goniatitid ammonoids from the middle and upper Devonian. The family is included in the suborder Tornoceratina and the superfamily Tornoceratoidea.

<i>Clymenia</i> (ammonite) genus of molluscs (fossil)

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Gonioceras is an extinct genus of actinocerid nautiloidean cephalopods typified by a broad, low shell; flattened ventrally, convexly rounded dorsally; top and bottom meeting at an acute angle along the sides. In most the shell is rather thin, especially along the lateral portion. The aperture is contracted. Sutures from broad ventral and dorsal lobes, more narrowly rounded ventro-lateral and dorso-lateral saddles, and sharp pointed lateral lobes; more complex than in later Lambeoceras. The siphuncle is typically subcentral but may be closer to the venter; armenocerid in form with short segments and very short brims and containing a straight endosiphuncular canal system.

Ussurites is an extinct ammonoid cephalopod genus belonging to the suborder Phylloceratina and is included in the family Ussuritidae. Its range is restricted to the early Middle Triassic, (Anisian)

Tetragonoceras is an extinct prehistoric nautiloid genus from the nautilid family Tetragonoceratidae that lived during the Middle Devonian, found in Canada.

Neocycloceras is an extinct genus of nautiloid included in the Pseudorthocerida that lived during the Late Devonian and Mississippian. Neoclycloceras is characterized by a slender, generally circular shell with slightly oblique,sinuous surficial annulations. Its sutures have dorsal and ventral saddles and lateral lobes and become more oblique with age. Saddles point forward, lobes to the rear. Dorsal saddles are broad and low but the ventral ones are high and conspicuous. The siphuncle is located between the center and venter and is nummuloidal, composed of rounded expanded segments, the inside of which contains a continuous laminar lining that is thickest in the middle of the segments and thinnest at the septal necks. Neocycloceras has been found in Pennsylvania in North America and in Morocco in north Africa.

The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida

Biloclymenia is a genus in the ammonoid order Clymeniida which is characterized by a dorsal retrosiphonitic siphuncle with long adapically pointing septal necks.

Raymondiceratinae is a subfamily of Upper Devonian cheiloceratid goniatites in which the sutures have 4 distinct lobes and the growth lines are convex. The subfamily includes three genera.

Hypophylloceras is a Cretaceous ammonite with a finely ribbed, compressed, involute shell; some having periodic stronger ribs or folds. The suture is complex, with large, asymmetric and finely divided lobes; the 1st lateral being much larger than the external (=ventral) and 2nd lateral lobes. Saddle endings commonly not phylloid.

Bisatoceras is a late Paleozoic Ammonoidea; a member of the goniatitid family Bisatoceratidae.

Neoglaphyrites is a gonititid ammonite that lived during the latest Pennsylvanian and early Permian. Its shell is ellipsoidal and moderately involute; the umbilicus deep and typically less than 15 per cent of the shell diameter but in some species closer to 20 per cent. Delicate growth lines forming ventral and lateral sinuses and ventrolateral and dorsolateral salients have been found on Canadian Arctic specimens. The suture is characterized by the ventral lobe split into two broad prongs that are separated by a high median ventral saddle; prongs closely approximate the width of the first lateral lobe. The first lateral saddle is evenly rounded and is nearly symmetrical. The umbilical lobe is V-shaped and internal lobes are deep and narrow.

Dactylioceratidae family of molluscs (fossil)

The family Dactylioceratidae comprises Early Jurassic ammonite genera with ribbed and commonly tuberculate shells that resembled later Middle Jurassic stephanoceratids and Upper Jurassic perisphinctids. Shells may be either evolute or involute.

Sturia is a genus of ceratitid ammonoids from the Lower Triassic with an ammonitic suture.

Eophyllites is a genus of ammonoid cephalopods from the Lower Triassic and a predecessor of genera like Monophyllites and Ussurites.

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