The earliest known fully shelled turtles are the late Triassic "Odontochelys", "Chinlechelys" and "Proganochelys". The first-named genus was aquatic, but the second was probably terrestrial. They already had many advanced turtle traits, and thus probably had many millions of years of preceding turtle evolution and species in their ancestry. They did lack the ability to pull their heads into their shell (and they had a long neck), and ("Odontochelys") had a long, spiked tail ending in a club, a body form similar to that of ankylosaurs, resulting from convergent evolution.