THE RUMINANTS (ARTIODACTYLA, MAMMALIA) FROM THE LOWER MIOCENE OF CETINA-DE-ARAGON (PROVINCE OF ZARAGOZA, ARAGON, SPAIN)

The study of the lower Miocene ruminants from Cetina de Aragon has per mitted the identification of five species. Three of these, Andegameryx andegaviensis Ginsburg, Pomelomeryx gracilis (Pomel), and Oriomeryx m ajor (Viret), were previously found in localities in France. The oldes t known record of Andegameryx andegaviensis Ginsburg is from Cetina de Aragon. The new material from Cetina de Aragon, determined as Oriomer yx major proves the close affinities of this species with Amphitragulu s elegans. The other two species, Dremotherium celinensis nov. sp. and Bedenomeryx truyolsi nov. sp., are described for the first time from this locality. Dremotherium cetinensis nov. sp. is differentiated from D. feignouxi by its more hypsodont dentition. B. truyolsi nov. sp. is a large-sized species which has its last known occurrence in Cetina d e Aragon. The species described from Cetina de Aragon provide firm evi dence of the existence of three well-defined ruminant lineages in the early Miocene. The first lineage is formed by Pomelomeryx, Oriomeryx a nd Bedenomeryx which, together with Amphitragulus, form a homogeneous group of which the larger-sized species could be related to palaeomery cids. The second lineage is represented by Dremotherium whose evolved dental morphology is comparable to that found in the first cervids. Fo r this reason we have related Dremotherium to this pecoran family. The third lineage is formed by Andegameryx. The phylogenetic relationship of Andegameryx with the two above-mentioned lineages and with the bov ids and giraffids appears problematical because of its primitive denta l morphology. This study includes an updated list of the mammal fauna from Cetina de Aragon, with the exception of the Marsupialia, Insectiv ora and Chiroptera. According to its composition the rodent assemblage may be correlated to the lower part of early Miocene Standard zone MN 2.