Stelladens

{{Short description|Extinct genus of mosasaurine}}

{{Speciesbox

| fossil_range = Late Cretaceous, {{fossilrange|Maastrichtian|Maastrichtian|Maastrichtian}}

| image = Stelladens teeth - Longrich et al 2023.png

| image_caption = Holotype teeth

| display_parents = 2

| genus = Stelladens

| parent_authority = Longrich et al., 2023

| species = mysteriosus

| authority = Longrich et al., 2023

}}

Stelladens (meaning "star tooth") is an extinct genus of mosasaurine mosasaurs from the Late Cretaceous Ouled Abdoun Basin of Morocco. The genus contains a single species, S. mysteriosus.{{Cite journal |last1=Longrich |first1=Nicholas R. |last2=Jalil |first2=Nour-Eddine |last3=Pereda-Suberbiola |first3=Xabier |last4=Bardet |first4=Nathalie |date=2023 |title=Stelladens mysteriosus: A Strange New Mosasaurid (Squamata) from the Maastrichtian (Late Cretaceous) of Morocco |journal=Fossils |language=en |volume=1 |issue=1 |pages=2–14 |doi=10.3390/fossils1010002 |issn=2813-6284 |doi-access=free |hdl=10810/64193 |hdl-access=free }}

Discovery and naming

File:Stelladens dentary - Longrich et al 2023.png]]

The Stelladens holotype specimen, MHNM.KHG.1436, was discovered in the Sidi Chennane phosphate mine (Lower Couche III) of Oulad Abdoun Basin in Khouribga Province, Morocco. The specimen consists of a partial left dentary and two associated teeth, which is estimated to belong to an individual around {{convert|5|m|ft}} in total body length.

In 2024, Longrich et al. described Stelladens mysteriosus as a new genus and species of mosasaurs based on these fossil remains. The generic name, Stelladens, combines the Latin words stella, meaning "star" and dens, meaning "tooth", in reference to the shape of the teeth. The specific name, mysteriosus, derives from the Latin mysterium, meaning "mystery", referencing the unusual tooth morphology.

Undescribed teeth potentially referable to Stelladens have also been reported from the younger Upper Couche III in the Sidi Chennane locality.{{Cite journal |last1=Longrich |first1=N. R. |last2=Pereda-Suberbiola |first2=X. |last3=Jalil |first3=N.-E. |last4=Bardet |first4=N. |year=2024 |title=A New Species of the Durophagous Mosasaurid Carinodens from the Late Maastrichtian Phosphates of Morocco and Implications for Maastrichtian Mosasaurid Diversity |journal=Diversity |volume=17 |issue=1 |at=25 |doi=10.3390/d17010025 |doi-access=free |bibcode=2024Diver..17...25L }}

In 2024, Sharpe et al. argued that tooth-based holotypes such as those of Xenodens and most species of Carinodens generally lack sufficient character and variation data to be properly diagnostic, and included the study which described Stelladens as an example of undiagnostic holotypes.{{Cite journal |last1=Sharpe |first1=Henry S. |last2=Powers |first2=Mark J. |last3=Caldwell |first3=Michael W. |date=2024-12-16 |title=Reassessment of Xenodens calminechari with a discussion of tooth morphology in mosasaurs |journal=The Anatomical Record |language=en |doi=10.1002/ar.25612 |issn=1932-8486|doi-access=free |pmid=39682068 |quote=Although a larger-scale analysis of the failure of many paleontological species to meet this recommendation, and thus their poor taxonomic utility, is outside the bounds of this contribution, we argue that most of the existing species of Carinodens, Xenodens calminechari, and other tooth-based holotypes among Mosasauridae (e.g., Arambourg, 1952; Longrich et al., 2023) are known from nondiagnostic types.}}

References