|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|G. Arratia et al. 2002||Rajiform batoid characterized by very small teeth, less than 1mm in width. Dentition heterodont. All teeth asymmetrical. Crown-root junction not incized. Neck collar broad and lingually overhung by the uvula. Anterior teeth with a pair of low and blunt lateral cusplets. Cusplets reduced laterally. Teeth longer than wide in anterior to anterolateral position, wider than long in more lateral positions. Labial contour rounded and labially projected over the root. No protuberance or apron. Labial visor not very broad or flat. Tooth crown ornamentation con- fined to the inside of the labial visor and labial part of the neck collar. Transverse crest sharp. Central cusp low, pointed, and distally displaced. Lateral heels of crown convex in anterior and anterolateral rows, mesial heel continuous with apex and distal heel convex in lateral teeth. Lingual face not very steep or abrupt. Central uvula massive and more or less long with abrupt and steep club-like posterior edge in anterolateral teeth. Lateral uvulae absent. Root massive, wide, and displaced lingually. Labial face vertical and straight, only slightly higher than the lingual face. Root lobes oblique and laterally protruding from the crown. Lobes narrow and V-shaped. Groove lingually narrow with posterior notch, labially wide. Lingual opening of notch displaced below the median uvula in anterior teeth. One to two pairs of marginolingual foramina. Central foramen wide and placed posteriorly in groove.|