Meiolaniformes

Meiolania is an extinct genus of meiolaniid stem-turtle native to Australasia throughout much of the Cenozoic. Meiolania was a large turtle, with the shell alone ranging from in length. Four species are currently recognized, although the validity of two of them is disputed. Meiolania was first described as a species of lizard related to Megalania by Richard Owen towards the end of the 19th century, before the continued discovery of additional fossils solidified its placement as a kind of turtle.

Meiolaniidae is an extinct family of large, probably herbivorous stem-group turtles with heavily armored heads and clubbed tails known from South America and Australasia. Though once believed to be cryptodires, they are not closely related to any living species of turtle, and lie outside crown group Testudines, having diverged from them around or prior to the Middle Jurassic. They are best known from the last surviving genus, Meiolania, which lived in Australia from the Miocene until the Pleistocene, and insular species that lived on Lord Howe Island and New Caledonia during the Pleistocene an

Niolamia is an extinct genus of South American meiolaniid turtle with a long and complex history. Like its relatives, Niolamia was a robust and heavily armored terrestrial turtle with large, horn like scales covering its head and a tail encased by rings of bone. This heavily armored build may have served the animal during intraspecific combat during courtship, though such encounters likely did not involve the horns and frill, which are thought to serve more of a display function. Scans of the skull reveal that Niolamia likely had a great sense of smell but only low frequency hearing, indicatin

Meiolaniformes is an extinct clade of stem-group turtles, defined as all taxa more closely related to Meiolania than to Cryptodira and Pleurodira. It is known from the Early Cretaceous to the Holocene of Australia, Oceania and South America. Some Eurasian taxa have been suggested to be part of the group, but this is disputed.

Warkalania is an extinct genus of Australian meiolaniid turtle from the Oligocene or early Miocene of Riversleigh, Queensland. While other meiolaniids are known for their elaborate headcrests or long horns, Warkalania only possesses very short horns that form a somewhat continuous ridge across the back of the head. The only known species of this genus, Warkalania carinaminor, is the oldest named meiolaniid turtle of Australia.

Patagoniaemys is an extinct genus of stem turtle known from the late Cretaceous (Campanian to Maastrichtian age) of central Patagonia, Argentina. The genus contains two species: the type species, Patagoniaemys gasparinae, named in 2011, and a second species, Patagoniaemys aeschyli, named in 2026. It is a relatively large taxon with an oval-shaped carapace that has a large nuchal notch and many pits and grooves over its surface.

Ninjemys oweni is an extinct large meiolaniid stem-turtle from Pleistocene Queensland and possibly New South Wales (Australia). It overall resembled its relative, Meiolania, save that the largest pair of horns on its head stuck out to the sides, rather than point backwards, the larger scales at the back of its skull and the tail club which is made up of only two tail rings rather than four. With a shell length of approximately it is a large turtle and among the largest meiolaniids. Ninjemys is primarily known from a well preserved skull and associated tail armor, which were initially thought t