Basal middle Miocene Listriodontinae (Suidae, Artiodactyla) from Madrid, Spain

Abstract

Excavations in basal middle Miocene deposits in the Madrid Basin (Old Mahou Brewery, Los Nogales, La Hidroeléctrica, Guadarrama I, Barajas) have yielded interesting assemblages of fossils, among which the listriodont suid Listriodon retamaensis Pickford & Morales, 2003, is well represented. Much of the material is juvenile, and several of the permanent teeth are unworn, permitting detailed observations to be made of the fine structures of the crowns, which was not possible with the original hypodigm of the species from Retama due to the heavy wear on most of the teeth in that sample. Refinement of the definition of the species is thus possible. Los Nogales also yielded two teeth of the small tetraconodont suid Retroporcus complutensis