Lycideops
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''Lycideops'' is an extinct
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of
therocephalia Therocephalia is an extinct suborder of eutheriodont therapsids (mammals and their close relatives) from the Permian and Triassic. The therocephalians ("beast-heads") are named after their large skulls, which, along with the structure of their ...
ns from the
Late Permian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...
of South Africa. 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 specime ...
is ''Lycideops longiceps'', named in 1931 by South African paleontologist
Robert Broom Robert Broom FRS FRSE (30 November 1866 6 April 1951) was a British- South African doctor and palaeontologist. He qualified as a medical practitioner in 1895 and received his DSc in 1905 from the University of Glasgow. From 1903 to 1910, he ...
. Fossils of ''Lycideops'' come from the ''Dicynodon'' Assemblage Zone of the
Beaufort Group The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa. It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup. It follows conformably after the Ecca Group and unconformably underli ...
. ''Lycideops'' is a member of the
family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Lycideopidae. Like other lycideopids, ''Lycideops'' has a long snout.


Phylogeny

''Lycideops'' has been included in several
phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
analyses, including those of Huttenlocker (2009), Huttenlocker ''et al.'' (2011), and Sigurdsen ''et al.'' (2012). All place ''Lycideops'' within the advanced therocephalian clade Baurioidea. Huttenlocker (2009) and Huttenlocker ''et al.'' (2011) found it to group with '' Regisaurus'' and ''
Scaloposaurus ''Scaloposaurus'' is an extinct genus of carnivorous therocephalians living during the Permian 259.0—254.0 Ma existing for approximately . Taxonomy ''Scaloposaurus'' was named by Owen (1876). It was assigned to Therocephalia by Broom (1913); ...
'' as shown in the
cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...
below: The analysis of Sigurdsen ''et al.'' (2012) came to a different result, grouping ''Lycideops'' with '' Tetracynodon'' and '' Choerosaurus''. The clade including these three genera was called Lycideopidae, and ''Lycideops'' was the most basal member of the group. Characteristics that unite ''Lycideops'' with ''Tetracynodon'' and ''Choerosaurus'' include the presence of five
incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...
s on each side of the lower jaw (a derived characteristic given that most other eutherocephalians have four), a
lacrimal bone The lacrimal bone is a small and fragile bone of the facial skeleton; it is roughly the size of the little fingernail. It is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders. Several bony landmarks of ...
that touches the nasal bone, and a contact between the
maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...
and the
vomer The vomer (; lat, vomer, lit=ploughshare) is one of the unpaired facial bones of the skull. It is located in the midsagittal line, and articulates with the sphenoid, the ethmoid, the left and right palatine bones, and the left and right max ...
in the palate. Below is a
cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...
from the analysis:


References

Baurioids Therocephalia genera Lopingian synapsids of Africa Fossil taxa described in 1931 Taxa named by Robert Broom Lopingian genus first appearances Lopingian genus extinctions {{paleo-therapsid-stub