Acynodon undetermined

AFF. ACYNODON SP.

Localities: Barranc de la Boïga, Serrat del Rostiar-1, L’Espinau, Blasi-2, Bastur Poble.

Material: IPS-96633, IPS-96653, IPS-96657, IPS-96667, IPS-96674, IPS-96676, IPS-96704, IPS-105918, MCD-4842, MPZ-2017/1137, MPZ-2017/1138 ( Fig. 4I–P View Figure 4 ).

Description: Reminiscent of morphotype VII, these teeth show low and rounded crowns, and the enamel is ornamented with parallel basiapical ridges. Crowns are between 0.7 and 2.3 mm high basiapically and 0.9‒2.7 mm wide mesiodistally. However, this morphotype is labiolingually compressed, regardless of their size and overall shape (i.e. the tooth position) ( Fig. 4I–P View Figure 4 ). The ornamentation also differs from that seen in the teeth from Serrat del Pelleu in being stronger and composed of well-marked longitudinal ridges, which cover the apical half of the crown ( Fig. 4W View Figure 4 –AA). The carinae are also unserrated, but both mesial and distal carinae are well marked and run completely from the base to the apex ( Fig. 4Z View Figure 4 –AD). No apical wear facet is observed.

Remarks: This morphotype differs from the somewhat similar morphotype VI in the orientation of the enamel ridges and the degree of lateral compression. It also differs from the morphotype VII in the lateral compression, the lateral carinae and the absence of the apical facet.

The shape and morphological features of this morphotype match well with teeth referred to Bernissartiidae (e.g. Puértolas-Pascual et al., 2015a). However, bernissartiids are mainly restricted to the Early Cretaceous of Europe with only doubtful records from the Lower Cenomanian onwards ( Puértolas-Pascual et al., 2016). Furthermore, this type of teeth might also be present in other durophagous crocodyliforms. The most likely candidate, due to chronostratigraphical and geographical ranges, is Acynodon ( Buscalioni et al., 1997; Martin, 2007; Delfino et al., 2008b). Nevertheless, Acynodon shows more rounded teeth, lacks lateral carinae in posterior positions and bears a central apical crest, unlike morphotypeVIII. Futhermore, teeth in this morphotype fall outside the range of variability observed in the tooth-bearing jaw remains from Laño site referred to Acynodon . Hence, we prefer to leave their taxonomic affinity in open nomenclature.

ALLODAPOSUCHIDAE ( NARVÁEZ, BROCHU, ESCASO, PÉREZ-GARCÍA & ORTEGA, 2015)