Agassizilia
| Agassizilia Temporal range:
| |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | †Pycnodontiformes |
| Family: | †Pycnodontidae |
| Genus: | †Agassizilia Cooper and Martill, 2020 |
| Species | |
| |
Agassizilia is an extinct genus of both freshwater and marine pycnodont fishes from the mid-late Cretaceous (Albian-Turonian). The genus contains two species: A. erfoudina from freshwater deposits of the Kem Kem Group in south-east Morocco and A. barberi of the marine deposits of the Marlbrook Marl of Arkansas, US. The genus is named after paleontologist Louis Agassiz.[1][2]
It was described in 2020 from an isolated prearticular bone (lower jaw) with a unique tooth arrangement on its dental pavement which differentiates it from all other known pycnodont genera. It is the first new genus of pycnodont fish to be found in the Moroccan Kem Kem Group. Although the rest of its skeleton is unknown, the pavement of blunt delicate teeth on the holotype suggests that it fed of soft shelled invertebrates such as shrimp or ostracods. It was found alongside several other typically marine pycnodont genera in a freshwater river system, suggesting a possibly amphidromous lifestyle.[1]
Later in 2020, the species A. barberi from the US, which was previously assigned to Anomoeodus, was reclassified to Agassizilia due to it having more than four true tooth rows, much like A. erfoudina and unlike other members of Anomoeodus.[2]