Jurassic Period

Leedsichthys

Leedsichthys was a very large prehistoric saltwater fish which lived during the middle and late Jurassic Period, circa 165-150 million years ago. It was named in 1889 in honor of Alfred N. Leeds who found the first specimen. Leedsichthys belonged… Read More ›

Aegirosaurus

Aegirosaurus leptospondylus was a 6 foot long ichthyosaur which lived in the seas around Europe during the late Jurassic Period and early Cretaceous Period, roughly 147-135 million years ago. Aegirosaurus belonged to a family of ichthyosaurs called the ophthalmosaurids (Bardet… Read More ›

Dimorphodon

Dimorphodon was a species of pterosaur that lived during the early Jurassic Period about 195-190 million years ago. It measured over 3 feet long from its nose to the end of its long tail (which may or may not have… Read More ›

Diplurus

Diplurus was a 3 foot long freshwater coelacanth fish which lived in the northeastern United States during the late Triassic and early Jurassic Periods, approximately 220-190 million years ago. It is divided into three species: D. longicaudatus, D. newarki, and… Read More ›

Anchisaurus

Anchisaurus was a prosauropod dinosaur whose fossils have been found in America’s northeastern states of Massachusetts and Connecticut within rocks dated to the beginning of the Jurassic Period, about 200-190 million years ago. Anchisaurus is one of the more well-known… Read More ›

Lissodus

Lissodus was a prehistoric shark which lived from the early Triassic to the middle Cretaceous Period, about 250 to 110 million years ago, give or take. Named in 1835, it was a member of a group of sharks called the… Read More ›

Polyacrodus

NOTE: This article was originally published on May 4, 2022. On December 30, 2025, it was updated and re-uploaded. Polyacrodus was a genus of prehistoric shark, composed of several species, with fossils found in North America, South America, Europe, Asia, and… Read More ›