The Portland Formation is a geological formation in the northeastern United States. It dates back to the Early Jurassic

Early Jurassic

The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...

.

Vertebrate fauna

Dinosaur coprolites located in Massachusetts, USA. Ornithischian tracks located in Massachusetts and Connecticut, USA. Theropod tracks located in Massachusetts

Massachusetts

The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

 and Connecticut, USA. Prosauropod tracks located in Massachusetts and Connecticut, USA.

Dinosaur Dinosaur Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of... s reported from the Portland Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Ammosaurus Ammosaurus Ammosaurus is a genus of sauropodomorph dinosaur from the Early and Middle Jurassic Period of North America. At 4 meters in length, it was small compared to some other members of its suborder, which included the largest animals ever to walk the Earth...	A. major	Connecticut
Anchisaurus Anchisaurus Anchisaurus is a genus of basal sauropodomorph, and was an early herbivorous dinosaur. Until recently it was classed as a member of Prosauropoda. The name comes from the Greek αγχι/agkhi...	A. polyzelus	Connecticut Massachusetts		"Nearly complete skull and skeleton, fragmentary skeleton, adult."
	A. solus	Connecticut
Podokesaurus Podokesaurus Podokesaurus was a small carnivorous dinosaur of the Early Jurassic Period , and as such is one of the earliest known dinosaurs to inhabit the eastern United States . The small, bipedal carnivore was about 90 cm long and 0.3 m tall...	P. holyokensis	Connecticut		Partial postcranial skeleton.	All known remains of this species have been destroyed.