A museum-worthy item. EXCEPTIONALLY RARE LARGE DOUBLE MESOSAUR SKELETON. The mesosaur was one of the first reptiles to live in the water since the amphibians have appeared. In fact it had numerous specializations for underwater life: palmed legs, a hydrodynamic and flexible body and a long tail supported by flaps of skin growing on the edges. Like ordinary lamantine, it also had very thick ribs. They are found in Permian rocks in South America and South Africa, indicating that these two continents were joined at the time. The fossil plate measuring 61,5 cm inches by 42 cm at its outer points. Both specimens preserve many stunning details: complete skull( the right specimen preserves the head laied on the neck. Thin large teeth are visible, large tails, caudal vertebrae are preserved as manus and pedes, showing the 2-3-4-5-5 phalangeal formula. All the bones are well inflated, not flat or smashed. Condition: For the size of this specimen the matrix is been restored, professionally prepared and glued in four parts: in the extraccion of large specimens like this is normal for the matrix to break into several parts. Provenance: The fossil was purchased in bad state from an old Japanese collection and does come with the original purchase receipt dated several years ago. Stereosternum tumidum (meaning "rigid chest") (Stereos, Greek: “solid, firm”; Sternon, Greek: “chest, breastbone”) is an extinct genus of mesosaur marine reptile from the Early Permian. Stereosternum was about 75 centimetres in length as an adult. Many of the ribs and the Haemal arches are thickened with bone or have a pachyostotic characteristic, which would have helped the animal to be able to dive deep in the water as a counteracting force against buoyancy. Species: Stereosternum timidum Matrix dimensions: 61,5 x 42 x 3 cm Fossil size: unrolled 75 and 63 cm Period: Lower Permian Beautiful elegant and heavy custom made iron standing included. Shipping: The lot will be carefully packaged and shipped with tracking code. #ExclusiveCabinetofCuriosities