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''Laccosaurus'' is an extinct
monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
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 rhinesuchid
temnospondyl Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carbo ...
amphibian, 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 ...
being ''Laccosaurus watsoni''.


History of study

''Laccosaurus'' ''watsoni'' was named by paleontologist Sidney H. Haughton in 1925 on the basis of a largely complete skull from the ''Dicynodon-Theriognathus'' subzone of the ''Daptocephalus'' Assemblage Zone in South Africa. This genus and/or species has sometimes been synonymized with '' Uranocentrodon'', but this framework has not been adopted by recent workers. However, there is uncertainty related to the single referred specimen (BPI/1/4473); Eltink et al. (2019) consider this to belong to a different taxon, while Marsicano et al. (2017) considered it to belong to ''L. watsoni''.


Anatomy

Marsicano et al. (2017) were the most recent to diagnose this taxon and list the following unique combination of characters: "well-developed sensory sulci, infra-orbital sulcus with a step/S- like flexure between the orbit and the naris; width of interpterygoid vacuity pair greater than 90% of their length; vomers with field of denticles in symmetrical raised patches medially to the choanae; straight transverse vomerine tooth row; quadrate condyles projected behind the tip of the tabular horns; parasphenoid plate subrectangular, longer than wide, with a flat ventral surface; well-developed ‘pockets’, close to each other, thus the cristae musculares converge in the midline."


References

{{Taxonbar, from=Q6468165 Permian amphibians of Africa Monotypic vertebrate genera Prehistoric vertebrate genera Taxa named by Sidney H. Haughton Fossil taxa described in 1925