1) Animal order 2) Order sauropterygia 
Sauropterygia (`lizard flippers`) is an extinct, diverse taxon of aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Mesozoic before they became extinct at the end of that era. Sauropterygians are united by a radical adaptation of their pectoral girdle, designed to support p.....
• (n. pl.) Same as Plesiosauria.
Sauropterygia meaning lizar d flippers) are an order of extinct aquatic reptiles that includes plesiosaurs , nothosaurs , and perhaps placodonts (their classification is uncertain). Sauropterygians had four flipper-like limbs and a streamlined body; they were well adapted to life in the water. They were not dinosaurs, but were reptiles that also li...
Sau·rop`te·ryg'i·a noun plural [ New Latin , from Greek ... a lizard + ..., ..., a wing.] (Paleon.) Same as Plesiosauria . 
[n] - extinct marine reptiles: plesiosaurs
order Sauropterygia noun extinct marine reptiles: plesiosaurs; nothosaurs