Lepidosaur herbivory describes herbivorous lepidosaurs. Living non-avian reptiles form a paraphyletic group that consists of over 9,000 species of crocodiles, turtles, and lepidosaurs. The most diverse group, Lepidosauria, is first known from the Middle Triassic (240 million years ago) fossils, but likely originated in the Permian (approximately 300-250 million years ago). Living lepidosaurs, which include snakes, lizards, and rhynchocephalians, occupy a wide range of environments and niches. Though widely viewed as obligate carnivores, a small number of lepidosaurs are known to consume plant material. For example, there are roughly 3,300 species of living lizards and approximately 3% of them eat at least some plants. Though the exact definition of herbivory varies significantly between scientists, most define herbivorous lepidosaurs as those that consume plants for approximately 70-90% of its diet.