Daily dinosaur: Pteranodon

Pteranodon ( /tɨˈrænədɒn/; from Greek πτερ- "wing" and αν-οδων "toothless"), from the Late Cretaceous geological period of North America in present day Kansas,Alabama, Nebraska, Wyoming, and South Dakota, was one of the largest pterosaur genera and had a maximum wingspan of over 6 metres (20 ft). Pteranodon is known from more fossil specimens than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved, with complete skulls and articulated skeletons. It was an important genus of the animal community present in the Western Interior Seaway.

Pteranodon was a reptile, but not a dinosaur. By definition, all dinosaurs belong to the groups Saurischia and Ornithischia, which excludes pterosaurs. Nevertheless,Pteranodon is frequently featured in dinosaur books and is strongly associated with dinosaurs by the general public.

http://en.wikipedia.org/wiki/Pteranodon

Daily dinosaur: Ankylosaurus

Ankylosaurus (which is pronounced /ˌæŋkɨlɵˈsɔrəs/ [ANG-ki-lo-SAWR-us] or /æŋˌkaɪlɵˈsɔrəs/ [ang-KIE-lo-SAWR-us], and which means "fused lizard") is a genusof ankylosaurid dinosaur, containing one species, A. magniventris. Fossils of Ankylosaurus are found in geologic formations dating to the very end of the CretaceousPeriod (about 66.5–65.5 Ma ago) in western North America.

Although a complete skeleton has not been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal armored dinosaur. Other ankylosaurids shared its well-known features—the heavily-armored body and massive bony tail club—butAnkylosaurus was the largest known member of the family. 

http://en.wikipedia.org/wiki/Ankylosaurus

Daily dinosaur: Baryonyx

Baryonyx ("heavy claw") is a large, carnivorous dinosaur exposed in clay pits just south of Dorking, England. It is known from a single, young specimen, and apparently ate fish because remains of its last meal were discovered fossilized in its ribcage. It has been dated to the Barremian period of Early Cretaceous, approximately 125 million years ago.
Baryonyx is a very strange tetanuran. The design of its hips and pelvis suggests that it was bipedal for the purposes of on foot from place to place. However, its forelimbs were absurdly large for a theropod, telling that it also spent much of its time on all fours.

Like the dromaeosaurids, the person had a long curved claw on the thumb of each hand, which deliberates at about 31 cm (12 in). However, instead of having them on the rear foot, it is supposed that Baryonyx had them on the frontage feet.

The skeleton was not accepted exactly as it would have been in life (articulated), so the paleontologists reconstructing it placed them on the front feet because these legs were so powerful. The bone structure suggests a huge bulk of muscle ran down the sides of these front legs, and it therefore seems probable that the claws were placed here.

The long neck was fairly rigid, and was not S-shaped as in many other theropods. The skull was set at an sharp angle, not the 90° angle common in similar dinosaurs. The long jaw was distinctly crocodilian, and had 96 teeth, twice as many as its relations. Sixty-four of the teeth were located in the lower jaw (mandible), and 32 large ones in the upper (maxilla). The snout almost certainly bore a small crest.

The crocodile-like jaws and huge number of finely serrated teeth suggested to scientists thatBaryonyx was a fish-eater. As verification, a number of scales and bones from the fish Lepidotes were also discovered in the body cavity.

During the early Cretaceous, Wealden Lake covered the bulk of what is now northern Europe. Alluvial plains and deltas stretch from the uplands surrounding the area where London now stands and eventually ran into this great lake.

Baryonyx was exposed in these former deltas. In 1983, an amateur fossil hunter named William Walker came across an huge claw sticking out the side of a clay pit in Surrey. He received some help in retrieving the specimen, which was astonishingly intact.

The skeleton was agreed by Alan J. Charig and Angela C. Milner, Ph.D.s, of Natural History Museum in London. They available their description of the type species, B. walkeri, in 1986, and named it after Walker.

About 70 percent of the skeleton was improved, including the skull. Therefore paleontologists can make many useful deductions about Baryonyx from just a particular find.

It was the first carnivorous dinosaur exposed in England. The skeleton can be seen at theNatural History Museum in London. http://www.rareresource.com/baryonyx.htm