Tullimonstrum

genus of vertebrate from the Pennsylvanian geological period

Tullimonstrum, colloquially known as the Tully Monster, is an extinct bilaterian animal that lived in shallow tropical coastal waters of muddy estuaries during the Pennsylvanian geological period, about 300 million years ago. A single species, T. gregarium, is known. Its classification has been the subject of controversy, and interpretations of the fossil likened it to molluscs, arthropods, conodonts, worms, and vertebrates. It is unknown whether Tullimonstrum was a vertebrate or an invertebrate.

Tullimonstrum
Temporal range: Middle Pennsylvanian
The Tully Monster
Tullimonstrum gregarium fossil
(part and counterpart)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Clade: Bilateria
Genus: Tullimonstrum
Richardson, 1966
Type species
Tullimonstrum gregarium
Richardson, 1966