Pachylyroceras

Last updated

Pachylyroceras
Temporal range: Upper Mississippian
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Family:
Subfamily:
Genus:
Pachylyroceras

Ruzhentsev & Bogoslovskaia, 1971

Pachylyroceras is a large, generally subglobular, Upper Mississippian gonitite and included in the cephalopod subclass Ammonoidea.

Contents

Recognition

Pachylyroceras produced a large shell that is moderately evolute to moderately involute and thickly discoidal to subglobular, with a rather wide umbilicus. Surface sculpture consists of coarse, widely spaced longitudinal lirae. Constrictions where present are wide and deep. Its suture has a narrow bifurcated ventral lobe with slightly divergent to subparallel sides and a median saddle less than half the height.

Taxonomic position

Pachylyroceras, named by Ruzhentsev & Bogoslovskaia (1971), is included in the Neoglyphiocerataceae, (sometimes written Neoglyphioceratoidea), but its position within the superfamily varies according to whose classification.

The revised version of the Treatise, Part L (W. M. Furnish et al. 2009 ) includes Pachylyroceras as well as Alaoceras , Caenolyroceras , Dombarigloria , and Lyrogoniatites in the Neoglyphioceratidae and subfamily Lyrogoniatitinae. Dieter Korn (2006) also included Pachyhlyroceras in the Lyrogoniatitinae, but in the family Cravenoceratidae. Saunder, Work, and Nickoleava (1999) also included Pachyhlroceras in the Cravenoceratidae, but without regarding subfamilies. Others (GONIAT) include Pachylyroceras in the Gravenoceratid subfamily Cravenoceratinae instead.

The Treatise (Miller, Furnish, and Schindewolf 1957) includes Lyrogoniatites, from which Pachylroceras is probably derived, in the subfamily Neoglyphioceratinae along with Neoglyphioceras , but in the superfamily Goniatitaceae. The might suggest where Pachylyroceras might have been put, if it had been named and described at that time.

Related Research Articles

Alaoceras is an ammonoid cephalopod from the upper Paleozoic included in the goniatitid family Cravenoceratidae, named by Ruzhentsev & Bogoslovskaya in 1971.

Beyrichoceras is a genus belonging to the Goniatitid family, Muensteroceratidae, a group of ammonoids, extinct shelled cephalopods related to belemnites and recent coleoids and more distantly to the nautiloids

<i>Beyrichoceras</i> Genus of molluscs (fossil)

Beyrichoceras is a genus belonging to the Goniatitid family, Maxigoniatitidae that lived during the Mississippian Period

Goniatitina Extinct suborder of molluscs

Goniatitina is one of two suborders included in the order Goniatitida; extinct Paleozoic ammonoid cephalopods only distantly related to the Nautiloidea.

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.

Tornoceratoidea, also known as Tornocerataceae, is a superfamily of goniatitid ammonoids included in the suborder Tornoceratina. Tornoceratoidea, or Tornocerataceae, is essentially the Cheilocerataceae of Miller, Furnish, and Schindewolf (1957) in the Treatise Part L, revised to accommodate new taxa and new perspectives on the phylogeny.

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.

Gastrioceratoidea Extinct superfamily of molluscs

Gastrioceratoidea is one of seventeen superfamilies in the suborder Goniatitina, ammonoid cephalopods from the Late Paleozoic.

Adrianitidae is a family in the Adrianitaceae, a superfamily of ammonites in the cephalopod order, Goniatitida, known from the Middle Pennsylvanian to the Middle Permian.

Texoceras is an extinct ammonoid genus in the monotypic goniatitid subfamily Texoceratinae, included in the family Adrianitidae. These are shelled cephalopods more closely related to squids, belemnites, octopuses, and cuttlefish than to nautiloids from which they are derived.

Agathiceratidae, as revised, makes up the goniatitid superfamily Agathiceratoidea. Agathiceratidae, which lived from the Upper Carboniferous (Pennsylvanian) to the Middle Permian, combine related genera with subdiscoidal to globular shells that have a small umbilicus and goniatitic sutures and are prominently longitudinally lirate. The explanation for the Agathiceratidae is that for the Agathiceratoidea.

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.

Medlicottiidae is a family of ammonoid cephalopods belonging to the Prolecanitida, known from the Upper Carboniferous (Pennsylvanian) to the Early Triassic.

<i>Cyclolobus</i>

Clyclolobus is a smooth, essentially involute subdiscoidal goniatitid ammonoid that has sutures with a bifurcate ventral lobe, flared outwardly at the end, in which the halves may be secondarily trifurfate, ending in sharp, narrow projections. Lateral sutural elements follow an acuate line that swings first to the front, then sharply to the rear before becoming hidden by the next whorl. Saddles are narrow, cumulous in appearance with short, irregular, rounded sub-endings. Ventro-lateal lobes are trifurcate with pointed, thorn-like projections.

Clymeniida Extinct order of molluscs

Clymeniida is an order of ammonoid cephalopods from the Upper Devonian characterized by having an unusual dorsal siphuncle. They measured about 4 cm (1.6 in) in diameter and are restricted to Europe, North Africa, and possibly Australia.

Karagandoceratoidea is an Early Carboniferous (Mississippian) superfamily within the ammonoid order, Goniatitida, said to contain the Karagandoceratidae and Prodromitidae.

Lyrogoniatitites is a neoglyphiocercean ammonite, in the order Goniatitida, related to genera like Alaoceras, Cravenoceras, Dumbarigloria and Pachylyroceras.

Cravevoceras is an Upper Paleozoic ammonite in the goniatite family Cravenoceratidae, probably derived from Pachylyroceras and contemporary with other cravenoceratid genera like Caenolyroceras, Tympanoceras and later Alaoceras and Lyrogoniatites. It is also a member of the Neoglyphiocerataceae.

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

References