Photogrammetric 3D models of skeletal fragments of a marine reptile
of the family Elasmosauridae; Vega Island - Antarctica; Upper
Cretaceous; Snow Hill Island Formation. This marine reptile from
Antarctica was up to 6 metres long.
Plesiosaurs have hyperphalangy (an increase in the number of
phalanges compared to their ancestors). This is an evolutionary
adaptation that led to an increase in the surface area of the fins
in marine reptiles.
On the skeleton of the Cretaceous plesiosaurid in the image below,
the found parts highlighted in red are exhibited or stored in the
collections of the Czech Geological Survey.
Fragment of the pubic bone (os pubis) and parts of the ribs