In Bell and Polcyn's sampled analysis, Mosasauridae includes plesiopedal Dallasaurus as well as more derived hydropedal members, so limb grade alone is not treated as a family diagnosis.
claim:taxon:mosasauridae:taxonomyMosasauridae
Bell and Polcyn's sampled Mosasauridae includes both plesiopedal Dallasaurus and more derived hydropedal members; limb grade alone is not treated as a family diagnosis.
Represented range92–66 Ma
Content packageturtles-lepidosaurs
PBDBtxn:38049
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
The 92–66 Ma Mosasauridae display is a two-study sampled envelope: two Dallasaurus skeletons document a middle Turonian (~92 Ma) occurrence, and Mosasaurus hoffmanni NHMM 2007 093 occurs within one metre below the regional K/Pg boundary; neither edge is an exact global family FAD or LAD.
claim:taxon:mosasauridae:fossil-rangeThe profile's geographic examples are restricted to middle Turonian Dallasaurus skeletons from north-central Texas and latest-Maastrichtian Mosasaurus hoffmanni NHMM 2007 093 from the Maastricht type area; they are not a complete Mosasauridae distribution map.
claim:taxon:mosasauridae:biogeographyThe two incomplete Dallasaurus skeletons preserve cranial, axial and plesiopedal limb characters, and the cited analysis places that condition within Mosasauridae alongside independently acquired hydropedal limbs; this is a character-and-topology result, not a linear ancestor-to-descendant sequence.
claim:taxon:mosasauridae:morphologyBell and Polcyn distinguish small plesiopedal from larger hydropedal adaptive grades, while tooth-enamel carbon isotopes from five type-Maastrichtian mosasaur taxa support marine carnivory and resource partitioning; these samples do not establish one family-wide diet, foraging habitat, swimming mode or body size.
claim:taxon:mosasauridae:ecologyKnown limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
References
- Dallasaurus turneri, a new primitive mosasauroid from the Middle Turonian of Texas and comments on the phylogeny of Mosasauridae (Squamata)Bell, G.L. Jr; Polcyn, M.J. · 2005 · DOI 10.1017/S0016774600020965
- The youngest in situ record to date of Mosasaurus hoffmanni (Squamata, Mosasauridae) from the Maastrichtian type area, the NetherlandsJagt, J.W.M.; Cornelissen, D.; Mulder, E.W.A.; Schulp, A.S.; Severijns, J.; Verding, L. · 2008
- Open Tree of Life web servicesOpenTreeOfLife Project
- The Paleobiology Database application programming interfacePeters, S.E.; McClennen, M. · 2016 · DOI 10.1017/pab.2015.39
- Denormalized occurrence and taxon tables of the Paleobiology DatabaseThe Paleobiology Database Community; Kocsis, Á.T. · 2026 · DOI 10.5281/zenodo.21620933
- On diving and diet: resource partitioning in type-Maastrichtian mosasaursSchulp, A.S.; Vonhof, H.B.; van der Lubbe, J.H.J.L.; Janssen, R.; van Baal, R.R. · 2013 · DOI 10.1017/S001677460000010X