Mosasauroidea is a

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

of extinct marine

lizards Lizard is the common name used for all squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The ...

that existed during the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

. Basal members of this group consist of small

semiaquatic In biology, being semi-aquatic refers to various macroorganisms that live regularly in both aquatic and terrestrial environments. When referring to animals, the term describes those that actively spend part of their daily time in water (in ...

forms with terrestrial limbs ("plesiopedal"), while laters members include larger fully aquatic paddle-limbed ("hydropedal") forms commonly known as mosasaurs. These were traditionally grouped within their own separate

families Family (from ) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictability, structure, and safety as ...

, the

Aigialosauridae Aigialosauridae (from Ancient Greek, Greek, ''aigialos'', meaning "seashore", and ''sauros'', "lizard") is a family of Late Cretaceous semiaquatic Pythonomorpha, pythonomorph lizards closely related to the mosasaurs. Regarded by some paleontologi ...

and

Mosasaur Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Ancient Greek, Greek ' meaning 'lizard') are an extinct group of large aquatic reptiles within the family Mosasauridae that lived during the Late Cretaceous. Their first fossil remains wer ...

idae respectively. However,

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

studies have since found plesiopedal mosasauroids to be a non-monophyletic group, with some taxa nestled within the mosasaurids. Daniel Madzia and Andrea Cau in 2017 defined Mosasauroidea as "the most inclusive clade containing '' Mosasaurus hoffmannii'' and ''

Aigialosaurus dalmaticus ''Aigialosaurus'' is an extinct genus of Late Cretaceous marine or semiaquatic lizard classified as part of the family Aigialosauridae within the Mosasauroidea. Exclusively found in deposits of Cenomanian age near Hvar, Croatia, the genus contain ...

'', but not '' Dolichosaurus longicollis'', '' Adriosaurus suessi'', or '' Pontosaurus lesinensis''".

References

{{Taxonbar, from=Q1015249 Cenomanian first appearances Maastrichtian extinctions Taxa named by Charles Lewis Camp