Adrianitidae
Encyclopedia


Adrianitidae is a family in the Adrianitaceae
Adrianitaceae
Adrianitaceae 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:...

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

Members of the Adrianitidae, named by Schindewolf in 1931, and of the Adrianitaceae, have shells (conchs) that are discoidal to globular with umbilici that vary in form, and sutures with 10 to 30, more or less equal, lobes.

The Adrianitinae which come from the Lower and Middle Permian have sutures that form 14 to 30 lobes. Genera included Adrianites, Hoffmannia, Doryceras, Crimites, and Texoceras.
The Dumbaritinae which come from the Middle and Upper Pennsylvanian
Pennsylvanian
The Pennsylvanian is, in the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly . As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain...

 (U Carb) have sutures with only 10 lobes. Clinolobus, from the Middle Permian of Sicily, has about 14 lobes with the course of the external suture forming a V.

Classification

The Adriantidae contains three subfamilies, the Adrianitinae, Hoffmanniinae, and Texoceratinae. Most of the genera in the family, some 15 in number, are included in the Adrianitinae. The remaining two are included, one each, in the Hoffmanniinae and Texoceratinae.

Dunbarites and Clinolobus included in the Adrianantidae in the older edition of 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) have since then been reassigned; Dunbarites to the Schistocerataceae
Schistocerataceae
Schistocerataceae is one of seventeen superfamilies of the Goniatitina suborder. 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:...

 and Clinolobus to the Neoicocerataceae
Neoicocerataceae
Neoicocerataceae 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:...



The Emilitinae, established to include the most primitive members of the family, based on Emilites, have been reincorporated into the Adrianitinae. Pamiritella for which the Pamiritellinae
Pamiritellinae
Pamirioceras is an extinct genus of ammonite in the monotypic Adrianitidae subfamily Pamiritellinae. 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:* accessed on...

 was established is considered also part of the Adrianitinae.

Phylogeny

According to Saunders et al (1999), the Adrianitidae are derived from Clistoceras, a genus in the Somholitaceae, through Emilites, which in turn is the source for Pseudoemilites and Crimites. Pseudoemilites resulted in small groups that include Veruzhites and Nevadoceras as well. Crimites on the other hand gave rise to Neocrimites and Pamiritella which respectively are the source for the Adrianitinae and Pameritellinae. Crimites also gave rise to Aricoceras
Aricoceras
Aricoceras is an extinct genus of the Adrianitidae family. 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:...

and Neoaricoceras. The source for either Hoffmannia or Texoceras is unknown.

Older Taxonomy

In the taxonomies put forth by Miller, Furnish, and Schindewolf (ca 1960) in the Treatise on Invertebrate Paleontology, Part L, Ammonoidea
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...

, the Adrianitidae is divided into three subfamilies, the more advanced Adrianitinae based on Adrianites, the more primitive Dunbaritinae containing Dunbarites and Emilites, and the Clinolobitinae with just Clinolobus.
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