The Dinosaurs of Delaware
Delaware is a relatively small state, so it's no surprise that relatively few dinosaurs or prehistoric animals have been discovered there--but there have been a couple, as listed below. (See an interactive map of dinosaurs and prehistoric animals in the United States.)
It's not uncommon to find the scattered fossils of marine reptiles in parts of Delaware that were once submerged completely underwater. That explains why this state has yielded the shell fragments of various prehistoric turtles of the late Cretaceous period, including the relatively obscure Trionyx and Toxochelys.
The state fossil of Delaware, Belemnitella was a type of animal known as a belemnite--a small, squidlike critter that was eaten in bulk by the ravenous marine reptiles of the Mesozoic Era. Belemnites started to appear in the world's oceans about 300 million years ago, but this Delaware genus dates from about 70 million years ago, during the late Cretaceous period.
The dinosaur fossils discovered in Delaware mostly consist of teeth and toes, not enough evidence to attribute to a specific genus. However, paleontologists have broadly assigned these itty-bitty fossils to various hadrosaurs (duck-billed dinosaurs) and ornithomimids ("bird-mimic" dinosaurs), the remains of which washed out into the Delaware Basin tens of millions of years ago.
During the Mesozoic Era, much of modern-day Delaware was underwater. That explains the scattered, frustratingly incomplete remains of marine reptiles that have been discovered in this state, including the teeth and vertebrae of various mosasaurs, plesiosaurs and even prehistoric crocodiles (possibly including the gigantic Deinosuchus).
1. Prehistoric Turtles
It's not uncommon to find the scattered fossils of marine reptiles in parts of Delaware that were once submerged completely underwater. That explains why this state has yielded the shell fragments of various prehistoric turtles of the late Cretaceous period, including the relatively obscure Trionyx and Toxochelys.
2. Belemnitella
The state fossil of Delaware, Belemnitella was a type of animal known as a belemnite--a small, squidlike critter that was eaten in bulk by the ravenous marine reptiles of the Mesozoic Era. Belemnites started to appear in the world's oceans about 300 million years ago, but this Delaware genus dates from about 70 million years ago, during the late Cretaceous period.
3. Hadrosaurs and Ornithomimids
The dinosaur fossils discovered in Delaware mostly consist of teeth and toes, not enough evidence to attribute to a specific genus. However, paleontologists have broadly assigned these itty-bitty fossils to various hadrosaurs (duck-billed dinosaurs) and ornithomimids ("bird-mimic" dinosaurs), the remains of which washed out into the Delaware Basin tens of millions of years ago.
4. Marine Reptiles
During the Mesozoic Era, much of modern-day Delaware was underwater. That explains the scattered, frustratingly incomplete remains of marine reptiles that have been discovered in this state, including the teeth and vertebrae of various mosasaurs, plesiosaurs and even prehistoric crocodiles (possibly including the gigantic Deinosuchus).
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