Beyrichoceras is a genus belonging to the Goniatitid family, Muensteroceratidae

Muensteroceratidae

Muensteroceratidae is one of nine families of the Pericyclaceae superfamily. They are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopuses, and cuttlefish, and more distantly to the nautiloids.-References:...

, a group of ammonoids, extinct shelled cephalopods related to belemnites

Belemnoidea

Belemnoids are an extinct group of marine cephalopod, very similar in many ways to the modern squid and closely related to the modern cuttlefish. Like them, the belemnoids possessed an ink sac, but, unlike the squid, they possessed ten arms of roughly equal length, and no tentacles...

 and recent coleoids

Coleoidea

Subclass Coleoidea, or Dibranchiata, is the grouping of cephalopods containing all the primarily soft-bodied creatures. Unlike its sister group Nautiloidea, whose members have a rigid outer shell for protection, the coleoids have at most an internal bone or shell that is used for buoyancy or support...

 and more distantly to the nautiloids

Description

Beyrichoceratoides has a smooth involute discoidal shell with a very narrow umbilicus, non-crenulate biconvex growth lines, and well-developed ventro-lateral salients and deep hyponomic sinus. The ventral lobe of the suture is moderately narrow and straight sided; bifuracated with short prongs separated by a low median saddle. The first lateral and umbilical lobes are like those of Beyrichoceras, broad and V-shaped, only the first lateral one is more symmetrical in Beyrichoceratoides. The internal dorsal and flanking lobes are also like those of Beyrichoceras but with the flanking lobes set relatively further apart.

Derivation and Taxonomy

Beyrichoceratoides was derived from Muensteroceras near the beginning of the Carboniferous (early Mississippian) and is included in the Muesteroceratidae, a family assigned to the Goniatitid superfamily Pericyclaceae

Pericyclaceae

Pericyclaceae is one of seventeen superfamilies of the Goniatitina suborder. They are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopodes, and cuttlefish, and more distantly to the nautiloids.-References:...

.

Beyrichoceratoides was named by Bisat in 1924, based on Goniatites implicatus Phillips, 1836. Schindewolf, 1951, considered Beyrichoceratoides equivalent to Münsteroceras Hyatt 1884 as also presented in the Treatise

Treatise on Invertebrate Paleontology

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...

Part L,1957. Ruzhentsev,1960, considered Beyrichoceratoide a distinct genus as do Korn 2006 and Nikolaeva 2008.

Distribution and Range

Beyrichoceratoides has been found in the Lower Carboniferous (Mississippian) of Great Britain

Paleoecology

Beyrichoceratoides has been described as a "fast-moving nektonic carnivore". However its somewhat globular discoidal form suggest a small stalking or houvering nektonic or nekto-benthic ambush predator capable of sudden swift movements to either grab prey or escape predation. As with all known cephalopods, Beyrichoceratoides was undoubtedly carnivorous.