Lisowicia

Lisowicia
Temporal range: Late Triassic
Late Norian to Rhaetian
Left humerus and femur
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Suborder: Anomodontia
Clade: Dicynodontia
Family: Stahleckeriidae
Subfamily: Placeriinae
Genus: Lisowicia
Sulej & Niedźwiedzki, 2019
Species:
L. bojani
Binomial name
Lisowicia bojani
Sulej & Niedźwiedzki, 2019

Lisowicia is an extinct genus of giant dicynodont synapsid that lived in what is now Poland during the late Norian or earliest Rhaetian age of the Late Triassic Period, about 210–205 million years ago. Lisowicia is the largest known dicynodont, as well as the largest non-mammalian synapsid, reaching about 4.5 metres (15 ft) long, standing up to 2.6 metres (8.5 ft) tall at the hips and weighing around 5–7 metric tons (5.5–7.7 short tons), comparable in size to modern elephants. It was also one of the last dicynodonts, living shortly before their extinction at the end of the Triassic period. Fossils of a giant dicynodont were known from Poland since 2008, but Lisowicia was not named and officially described as a new species until late 2018.

Lisowicia is unique amongst dicynodonts for its erect posture, with all four limbs held upright directly under its body. This is similar to the limbs of living mammals and dinosaurs, but unlike the sprawling and semi-erect postures typical of all other dicynodonts (and indeed all other non-mammalian synapsids), and shares many independently evolved features of its limbs with large mammals. Lisowicia was the largest animal in its environment, and was comparable in size and ecology to the herbivorous "prosauropod" sauropodomorphs, which otherwise occupied the role of large high-browsing herbivores in most Late Triassic ecosystems. Prior to the discovery of Lisowicia, dicynodonts were suggested to have been outcompeted by sauropodomorphs and were incapable of achieving similarly large body sizes. Lisowicia may have evolved its large size in response to the absence of sauropodomorphs in its ecosystem in southern Poland, or alternatively may have acted as a direct competitor to them.