This lifeform is found widely in Eurasia. This lifeform is widespread in North America. This lifeform has been extinct for over 20,000 years.

Pterodactyls (Family Pterodactyl) reached their maximum development in the Cretaceous Period. There are about fifteen different species known in this family.

Winged Dinosaurs (Pterosauria Order) contain the various Pterodactyls. These were unusual creatures that could walk like lizards carrying their wings upright next to their front legs, They could also fly. Most scientists agree that these dinosaurs were not the ancestors of the birds that exist today despite their ability to fly. All members of this order are now extinct.

Although the Winged Dinosaurs (Pterosauria) reached their zenith of development in the Jurassic period, it is believed that they originated in the Triassic period due to the discovery of Peteinosaurus. It had a wingspan of about two feet.  

Peteinosaurus is placed in a unique family entitled the Family Dimorphodontidae. Dimorphodon, which is dated at about two hundred million years ago, is also in this family.

Winged Dinosaurs of the Jurassic and Cretaceous Periods are generally divided into two major groups, Rhamphorhynchoidea and Pterodactyloidea, each of which contains several families.

The Rhamphorhynchoidea and the Pterodactyloidea have many skeletal differences. However, the most obvious is that the Rhamphorhynchoidea have a long tail made up of extended vertebrae, and the Pterodactyloidea have a short tail.

The Rhamphorhynchoidea group originated at the end of the Triassic period and went extinct at the end of the Jurassic.

The Pterodactloidea group originated at the end of the Jurassic and went extinct at the end of the Cretaceous.

Some of the better-known families within these two groups are noted below:

            Rhamphorhynchoidea Group:

                  Family Anurognathidae*
                  Family Dimorphodontidae*
                  Family Ramphorhynchidae*

            Pterodactloidea Group:

                   Family Pterodactylidae*
                   Family Gallodactylidae
                   Family Germanodactlidae
                   Family Ctenochasmatidae
                   Family Dsungaripteridae
                   Family Pterodaustridae*

Generally, the size of the Pterosaurs increased from the Triassic to the Jurassic and from the Jurassic to the Cretaceous. Pteronodon and Quetzalcoatlus were exceptionally large. Pteronodon had a wingspan of about 30 feet, and Quetzalcoatlus might have had a wingspan of 75 feet, although Unwin estimates somewhat over 33 feet wingspan.

For an excellent review of Pterosaurs see the Illustrated Encyclopedia of Pterosaurs by Dr. Peter Wellinhofer.
Published by Crescent books in New York in l991.

Summary of Important Time Periods in Dinosaur history:

       Triassic Period      225  to  190  Million years ago
       Jurassic Period      190  to  135  Million years ago
       Cretaceous Period    135  to   65  Million years ago

Reptiles (Class Reptilia) are an ancient group of scaled  chordates. These scales may be permanently joined, as in the  turtles, or flexible, as in the snakes. Reptiles are land-based. Their eggs are laid on land and the young are air breathing.

Backboned Animals (Phylum Chordata) are the most advanced group of animals on earth. These animals are characterized by having a spinal cord or backbone. Most members have a clearly defined brain that controls the organism through a spinal cord. Fish, amphibians, reptiles, birds, and mammals are in this phylum.

Currently, some taxonomists believe that the fish should be divided into two groups (sharks and regular fishes) and that there are some other primitive groups in the phylum such as hagfish or lampreys.

Animal Kingdom contains numerous organisms that feed on other animals or plants. Included in the animal kingdom are the lower marine invertebrates such as sponges and corals, the jointed legged animals such as insects and spiders, and the backboned animals such as fish, amphibians, reptiles, birds, and mammals.