Alvarez Sierra & Daams, Pseudotheridomys fejfari sp. nov., Scripta Geol. 83 (1987) 19 Pseudotheridomys fejfari, a new species of Eomyidae (Rodentia) from the Ramblian (Lower Miocene) of northern Teruel (Spain) M. A. Alvarez Sierra & R. Daams M.A. Alvarez Sierra & R. Daams. Pseudotheridomys fejfari, a new species of Eomyi- dae (Rodentia, Mammalia) from the Ramblian (Lower Miocene) of northern Teruel (Spain). — Scripta Geol., 83: 19-26,1 fig., 1 pl., Leiden, May 1987. This paper, the third one in a series of monographs on the mammal faunas from the type areas of the Aragonian and Ramblian in the provinces of Zaragoza and Teruel, deals with the description of a new species of the Eomyidae, Pseudotheridomys fejfari. M.A. Alvarez Sierra, Departamento de Paleontologia, Facultad de Ciencias Geológi- cas, Universidad Complutense, Madrid, Spain; R. Daams, Museo Nacional de Ciên- cias Naturales, C.S.I.C., José Gutierrez Abascal 2, 28006 Madrid, Spain. Introduction 19 Systematic description 20 Discussion 25 References 26 Introduction In the summers of 1976-1983 extensive collections from micromammal-bearing localities have been made in the type area of the Aragonian and adjacent areas in the provinces of Zaragoza and Teruel. Preliminary reports on these faunas have been published by Daams & Freudenthal (1981), Daams & van der Meulen (1983), Cuenca et al. (1983), and Daams & van der Meulen (1984). The first detailed taxonomie study is that of the Glirinae by Daams (1985). The second study is the paper on the Ramblian Cricetidae by Sesé (this volume). The description of Pseudotheridomys feijfari nov. sp. is the third contribution to the taxonomie study of the various groups. All other groups of micro- and macromammals are at present under study by various Spanish and Dutch students. For the stratigraphie position of the localities and more complete information on the faunas, the reader is referred to the above-mentioned publications.