to represent juvenile and adult specimens of T. longobardicus. However, histology of the small specimens and restudy of the large specimens has shown that they each represent adult forms of two different species. The larger one-cusped morphotype was given a new species, T. hydroides, while the smaller tricuspid morphotype retained the name T. longobardicus. Paleobiology Skull biomechanics In T. hydroides, the connection between the quadrate and squamosal is loose, with the upper extremity of the quadrate hooking into a deep concavity on the squamosal. This would have enabled a degree of flexibility along the quadrate-squamosal contact, allowing the quadrate to swivel around an otic joint. This a condition is a form of cranial kinesis (movement among bones in the cranium) known as streptostyly, which is found in some living lizards. The quadrate is also loosely connected to the pterygoid, and the quadratojugal fails to contact the jugal, two qualities which allow movement of the quadrate without hindrance. While streptostyly is possible in the reconstructed skull, it cannot be demonstrated whether it was actively used by the living animal. Fragments of rod-like hyobranchial elements (throat bones) have been found in fossils of both T. hydroides and T. longobardicus. These hyobranchials are very slender and disarticulated, without a bony corpus (thickened “body” of the hyoid apparatus) to connect elements from either side of the throat. These traits indicate that Tanystropheus relied on biting and enlarged teeth to capture prey. Suction feeding is rejected, since it is correlated with a more robust and integrated hyoid apparatus. Soft tissue A specimen described by Renesto in 2005 displayed an unusual "black material" around the rear part of the body, with smaller patches in the middle of the back and tail. Although most of the material was amorphous, the portion just in front of the hip seemingly preserved scale impressions, indicating that the black material was the remnants of soft tissue. The scales seem to be semi-rectangular and do not overlap with each other, similar to the integument reported in a juvenile Macrocnemus described in 2002. The portion of the material at the base of the tail is particularly thick and rich in phosphate. Many small spherical structures are also present in this portion, which upon further preparation were revealed to be composed of calcium carbonate. These chemicals suggest that the black material was formed as a product of the specimen's proteins decaying in a warm,