four distal caudal centra, numerous large fragments referable to at least eight other vertebrae, seven proximal portions of hemal arches, three proximal portions (vertebral segment) of dorsal ribs, ten undetermined fragmentary ribs, poorly preserved right scapula and badly crushed right coracoid plate, distal head of the left ulna, and several autopodial elements represented by a fragmentary calcaneum, three metapodials, five non-ungual phalanges, an almost complete ungual phalanx, and two ungual phalanges lacking distal ends. These remains were firstly regarded as belonging possibly to Cotylorhynchus (cf Cotylorhynchus sp. in the publication of Ronchi et al.) or to a closely related taxon. Later, despite the absence of the most diagnostic elements (notably the skull) for the comparison with other caseids in general and with Cotylorhynchus in peculiar, the Sardinian specimen was assigned to a new genus named Alierasaurus, on the basis of some differences in feet anatomy. In 2017, Marco Romano and colleagues described other bones belonging to the same individual (some caudal vertebrae and fragments of chevrons and ribs). More recently, the same levels have yielded remains of an undescribed sphenacodontid pelycosaur, and footprints of a third animal which was only known in the south of France in slightly younger rocks (ichnogenus Merifontichnus from the La Lieude Formation (Wordian) in the Lodève basin). Taphonomy Remains of Alierasaurus were discovered grouped together on an area of a few square meters. Some lay on the ground, exposed by erosion, while others were still in the sediment. Most of the bones were isolated except for two foot bones and 8 caudal vertebrae found articulated. The bones still in place in the rock were not all on the same bedding plane but were buried at different depths within a 40 cm thick red siltstone layer. Several bones were fractured before burial. The taphonomy of the site indicates a complex burial process in several phases. Shortly after the death of the animal, the carcass was transported from the death place to a second burial place. This short transport was violent enough to break some bones. Subsequently, the corpse, still on the surface of the sediments, underwent a further rather short phase of decomposition before a new flash flood packed all the remains into a large amount of fine-grained sediment, transported them, and finally deposits them all together in a third place close to the previous one. This third phase of deposition explains why the bones are