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Unfortunately, only the apical part of the holotype tooth crown is preserved (GSM 1966: Fig. 6.2) and it is too incomplete to determine whether it was a maxillary or dentary tooth. For convenience, the tooth is described as a left dentary tooth in order to standardize terminology and facilitate comparisons. The labial crown surface is partially embedded within matrix.

The preserved portion of the crown has a subtriangular outline in lingual view, tapering apically (Fig. 6.2A). The unenameled labial surface of the crown is strongly convex mesiodistally, giving the tooth a D-shaped cross section in basal view. The lingual surface of the tooth is enamelled and bears a strong, slightly distally offset primary ridge that divides the crown surface into a large mesial and smaller distal portion. There are no secondary ridges. The enamel has a fine granular texture and faint parallel wrinkles extend horizontally across the crown surface mesiodistally (although these are not as prominent as in the figure provided by Newton [1892:fig. 1A]). The crown apex is unworn and the mesial and distal crown margins bear numerous denticles.

The mesial crown margin bears 16 large denticles, which are separated from each other by deep sulci. Basally, the denticles are oriented at approximately 45° to the apicobasal axis of the crown, but this angle changes progressively towards the crown apex, with more apically positioned denticles oriented at 80–90°. These denticles are subequal in size and are separated from the tooth apex by a group of 6 very small apically extending denticles, which are effectively small nubbins of enamel that are more like mammillae than true denticles. The largest, basal-most denticles each bear a row of mammillae (with around 4–5 mammillae per denticle). However, progressing apically around the crown margin the tips of each denticle bifurcate, to produce a forked structure: the apically positioned part of this fork bears a row of mammalliae (consisting of 2–4 mammillae), whereas the basally positioned part is comprised of a single, tongue-like process (Fig. 6.2B). This bifurcation of the denticle tips is subtle in lingual view, but more apparent in mesial view.

The denticles on the distal surface of the tooth are poorly preserved, but appear to follow similar trends in terms of size and orientation (12 large denticles are preserved, with a minimum of 2–3 small nubbin-like denticles just distal to the crown apex). Unfortunately, the poorer preservation of the apical-most distal denticles precludes examination of their tips, and it cannot be determined if they were bifurcated. However, the basal-most denticles possess single rows of mammillae that are identical to those on the basally positioned mesial denticles.