Painting by Heinrich Harder
Ichthyosaurs were dolphin-shaped; the body was streamlined for effortless swimming. The head had a long, triangular snout armed with many conical teeth, which were striated on the surface. The eyes were large, indicating the animal used well-developed vision to hunt its prey, which according to coprolite evidence was fish and cephalopods.
The body was robust, bearing four flippers, with the two front flippers twice the size of those at the rear. Fossilized impressions of the body in many specimens show a triangular dorsal fin as well as a vertical tail fin, with the end of the vertebral column forming the lower lobe. Total overall length was between one and thirty or more feet, depending on the species. Specimens also show the fact that ichthyosaurs were also ovoviviparous, that is, they gave birth to live young and, like dolphins, were born tail-first to avoid drowning.
Suborders, families, and genera
- Suborder Latipinnati
- Family Ichthyosauridae
- Genus Ichthyosaurus
- Family Ophthalmosauridae
- Genera Mollesaurus; Ophthalmosaurus; Undorosaurus
- Family Mixosauridae
- Genus Mixosaurus
- Suborder Longipinnati
- Family Shastasauridae
- Genera Californosaurus; Cymbospondylus; Delphinosaurus; Merriamia; Shastasaurus; Toretocnemus
- Family Stenopterygiidae
- Genus Stenopterygius
According to evolutionary science, the earliest animal that could be called an ichthyosaur was Utatsusaurus, which allegedly lived in the early Triassic Period some 245-250 million years ago. It has been claimed that ichthyosaurs evolved from this species, becoming some 80 or so species and thriving throughout the Mesozoic Era, only to become extinct at the end of the Cretaceous along with dinosaurs and flying reptiles.
Creationists maintain that ichthyosaurs were created by an act of God during the Creation Week as described in Genesis. In 1999 a fossil ichthyosaur skull and adjacent vertebrae were found in an abandoned rock quarry near Hauenstein, Switzerland. The skull as found was vertical, and was forced into three layers of matrix which have been dated by traditional scientific methods as spanning just over one million years. The discoverer, Dr Achim Reisdorf, tried to explain it as the fossilization of an animal only after the soft layers in which it lay had hardened up, despite the observed evidence that animal remains will decay and disintegrate with a few years as a result of scavenging or weather/water actions.