Opisthias is a genus of sphenodont reptile. The type species, Opisthias rarus, is known from the Late Jurassic (Kimmeridgian-Tithonian) Morrison Formation of western North America,[2][3] present in stratigraphic zones 2 and 4–6.[4]
Opisthias
Dinosaurs/Creatures in “Rulers of the Jurassic”
for Dinosaurs/Creatures in “Rulers of the Jurassic” in Our Ancient Past
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Our Ancient Past
