Lalieudorhynchus

Lalieudorhynchus is an extinct genus of caseid synapsids that lived during the Guadalupian (= Middle Permian) in what is now the south of France. The genus is only known by its type species, Lalieudorhynchus gandi, which was named in 2022 by Ralf Werneburg, Frederik Spindler, Jocelyn Falconnet, Jean-Sébastien Steyer, Monique Vianey-Liaud, and Joerg W. Schneider. Lalieudorhynchus is represented by a partial postcranial skeleton discovered in the Lodève basin in the central part of the Hérault department in the Occitanie region. It belongs to an individual measuring approximately in length. The degree of ossification of its bones, however, indicates that it was a late juvenile or still growing young adult. Based on the internal structure of its bones, the describing authors interpreted Lalieudorhynchus as a semiaquatic animal that may have had a lifestyle similar to that of hippopotamus, spending part of its time in water but returning to land for food, though the idea that caseids were semi-aquatic has been previously contested by other authors. It is geologically one of the youngest known representatives of the caseids. The phylogenetic analysis proposed by Werneburg and colleagues identified Lalieudorhynchus as a derived caseid closely related to the North American species "Cotylorhynchus" hancocki. The genus name is a combination of La Lieude located near the type locality, and "rhynchus", the Latinized form of the Greek "rhynchos" (the nose) sometimes used in the names of caseids. The specific epithet honours Georges Gand who worked on the Lodève basin for decades, notably on the La Lieude footprint slab, and co-organized and promoted the excavation campaigns for this caseid. Lalieudorhynchus is represented by a partial and disarticulated but well-preserved post-cranial skeleton. The holotype, represented by a series of bones cataloged UM-LIE 02–37, UM-LIE 39–41, UM-LIE 45 and UM-LIE 47, consists of about ten vertebrae (dorsal, sacral and caudal), about fifteen ribs, a complete right scapulocoracoid long, the dorsal branch of the left ilium, the right and left femora measuring long, and several foot bones (an astragalus, two tarsal elements and five phalanges).