Reesodus

Rees & Underwood (2002) found that Paleozoic material referred to the genus Lissodus should be assigned to two separate genera which they left unnamed. They assigned '''Lissodus' wirksworthensis from southern England, 'Lissodus' pectinatus from western Russia and 'Lissodus' sp.'' from central Russia to 'Palaeozoic Genus 2'. The genus Reesodus was erected in 2013 as a replacement name for 'Palaeozoic Genus 2', with the newly described Reesodus underwoodi from the Khuff Formation of Oman as the type species. Though the known material is identified as belonging to a hybodontiform, Reesodus cannot be confidently assigned to any family (though it is assumed to be close to Lonchidiidae) as the heterodonty pattern and the possible presence of enlarged lateral teeth cannot be assessed, thus it is listed as Hybodontiformes incertae sedis. Reesodus pectinatus was originally described in 1996 as Lissodus pectinatus, but has since been recognized to belong in this separate genus. It is known from teeth collected in Tournaisian-Viséan deposits in western Russia. ==Description==

Reesodus is known from fossil teeth characterized in having a mesio-distally expanded crown with a low profile, as many as 4 lateral cusplets and a very strong crown shoulder. These teeth may be ornamented with varying amounts and density of coarse folds. The labial peg is moderately or well-developed, often accompanied by protuberances near the base of the lateral cusplets and/or a labial root buttress. Compared to those of other hybodonts, the tooth roots of Reesodus are less porous. ==References==