Seymouria

Live reconstruction of Seymouria baylorensis

• USA
• Germany

Seymouria was a land vertebrate, which is counted among the so-called reptiliomorphen amphibians. Fossils of animals were found in the central southwestern United States and in Bromacker in Tambach -Dietharz in the Thuringian Forest. The genus was named after Seymour, Texas, where Seymouria was first found. Some skeletons are preserved in three dimensions, thereby Seymouria is the most studied genus of Seymouriamorpha. All fossils are of adult animals, remains of the larvae are not known. Seymouria lived in the semi-deserts of the Permian and was probably fairly common.

Features

Seymouria reached up to sixty centimeters in length and could by its relatively long, powerful limbs of the body higher rise above the ground than primitive land vertebrates. The legs were well ossified, while the distal end of the leg of most other Seymouriamorphen was still cartilaginous. Femur and humerus were robust. Seymouria had five toes on each foot. The front legs were shorter than the hind legs. Your proximal and distal ends were greatly expanded to provide the large muscle attachment areas. The wide vertebral arches were firmly fused with the vortex centers. Sutures are not visible. Scales were not found. Whether Seymouria was scaly, therefore, is not known.

The well-studied skull had at the back of the head a little pace Ralf Rochester, blood vessels and nerves course offered. The two wings legs were not separated and formed a closed palate. The middle ear probably possessed an eardrum, a well-preserved stapes transmitted the sounds to the inner ear. Notches in the anteroventral and posteroventral margin of the orbit are not found in other Seymouriamorphen and can be an autapomorphy of Seymouria.

Species

There are three types have been described:

• Seymouria baylorensis is the type species of the genus. All the fossils of the species were found in Texas.
• Seymouria sanjuanensis is known from Utah, New Mexico and Germany.
• Seymouria grandis is known from fragmentary remains from Oklahoma and Texas.

System

The group of Seymouriamorpha one of the mosaic shapes and combines characteristics of amphibians and reptiles. But it is closer to today's reptiles used as the Lissamphibia, today's amphibians.