''Xyrospondylus'' is an extinct
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of non-
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
ian
synapsids belonging to the
Edaphosauridae. The
type species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...
, ''X. ecordi'',
was named in 1982; it was originally named as a species of ''
Edaphosaurus'' in 1957.
It lived during the
Pennsylvanian (
Missourian) in
Kansas
Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...
and possibly also
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
[R. L. Carroll. 1988. Vertebrate Paleontology and Evolution 1-698 . Behrensmeyer/A. Behrensmeyer/M. Uhen] and the
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
is known from a single cervical
vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...
found in the
Stanton Formation
The Stanton Formation is a Formation (geology), geologic formation of limestone in Iowa, Nebraska, Missouri and Kansas. It preserves fossils dating back to the Carboniferous Period (geology), period. It is in the Upper Pennsylvanian series, formin ...
. A second specimen, consisting of a fragmentary pelvis, is also known. A third specimen, known from
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
, is known, but it probably does not pertain to ''Xyrospondylus''.
See also
*
List of pelycosaurs
This list of pelycosaurs is an attempt to create a comprehensive listing of all genera that have ever been included in the synapsida excluding therapsida and purely vernacular terms. The list includes all commonly accepted genera, but also genera t ...
*
List of therapsids
References
Edaphosaurids
Prehistoric synapsid genera
Carboniferous synapsids of North America
Paleontology in Kansas
Fossil taxa described in 1982
Taxa named by Robert R. Reisz
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