E.Jiménez, M.Á.Cuesta & S.Gil Tudanca: Vertebrados fósiles del Eoceno de Fuentesaúco(Zamora). 7-21.

Abstract.- In the present paper a mandible of Franzenium durense Cuesta, 1993 (Perissodactyla, Palaeotheriidae) and several fragments of Neochelys sp. and Neochelys aff. salmanticensis (Jiménez, 1968) (Chelonii, Pelomedusidae), coming from Fuentesaúco (Zamora), are described. This fauna suggest an age comprised between MP 16 and 17 (upper part of the upper Rhenanian and lower part of the lower Headonian), and is the first reference of such time in the Zamora province. It is also the third locality with Franzenium durense previously known only in Caenes (Salamanca) and Mazaterón (Soria).

Miguel Ángel Cuesta: Los Lophiodontidae (Perissodactyla, Mammalia) del Eoceno de la Cuenca del Duero (Castilla y León, España). 23-65.

Abstract:- In the present paper the systematic study of the Lophiodontidae (Perissodactyla, Mammalia) of the middle Eocene sites in the Duero Basin Eocene (Castilla y León, Spain) is made. Remains belonging to this family have been found in the localities of Casaseca, Corrales and Jambrina (middle part of the middle Eocene, MP 13-14) and in San Morales and Caenes (upper part of the middle Eocene, MP 16). In San Morales has been established the species Lophiodon sanmoralense nov.sp., belonging to the giant forms of the genus and characterized mainly by a special morfolgy of the M/3 hipoconulid. In Casaseca occur the greatest diversity of forms, with Lophiodon cf. tapirotherium, Paralophiodon aff. isselense and a third form poorly documented of smaller size. Paralophiodon aff. isselense is also present in Corrales; in this site and in Jambrina and Caenes there is fragmentary material atributable to Lophiodontidae.

M.R.Rivas Carballo: Estudio sistemático y morfológico de la Palinología miocena de la región suroriental de la Depresión del Duero (España). I: Esporas. 67-76.

Abstract:- Spores of Bryophyta and Pteridophyta coming from the south-eastern region of the Duero Basin (Spain) have been studied from systematic and morphological points of view. According to Armenteros (1986) the sediments analyzed are included in the Upper Aragonian-Vallesian passage of the continental miocene deposits. A locality map is given as well as a table showing the number of specimens and samples which yielded the spores described.

M.R.Rivas Carballo: Estudio sistemático y morfológico de la Palinología miocena de la región suroriental de la Depresión del Duero (España). II: Gymnospermae. 77-88.

Abstract:- Pollen morphology of the Gymnospermae from the South eastern Duero Basin (Spain) is described. The deposits analyzed belong to Upper Aragonian -Vallesian age (Armenteros, 1986). Pinaceae, Cupressaceae, Taxodiaceae, Cyacadaceae and Zamiaceae have been recognized in this region.

Hans- Volker Karl: Some aspects of evolution in Dermochelyidae (Reptilia, Testudines). 89-94.

Abstract:- Systematics and evolutionary relationships among the Dermochelyidae genus Psephophorus H.v.Meyer, 1847 are a still unsolved problem. The morphology of the humerus yields a characteristic criterion to clearify this question. A comparison of the humerus morphology reflects the relationships between palaeaertic Psephophorus species and their evolution to the recent Dermochelys.

E.Jiménez Fuentes & L.Alonso Andrés: Nuevos hallazgos de Trionychidae (Chelonii) en el Eoceno de Salamanca y Zamora. Consideraciones sobre los ecosistemas fluviales durante el Eoceno en la Cuenca del Duero. 95-114.

Abstract:- Several fragments of Trionyx sp. from a new deposit from the Headonian at Villoruela (Salamanca, Spain) are described. One fragment of the hyoplastra of Trionyx cf. michauxi Broin, 1977, from the Rhenanian of Corrales (Zamora, Spain) is also described; no Trionychidae have been hitherto recorded at this site. These findings broaden and clarify knowledge of the river ecosystems of the Eocene of the Duero Basin, permitting an initial synthesis concerning the evolution of such thems.

C. Fuentes Vidarte: Contribución al conocimiento de la fauna fósil de Torralba - Ambrona, Soria (España). Parte I. 115-126.

Abstract:- Estudied part of the fossil Fauna of the Torralba-Ambrona deposit, excavations 1961-63: birds, rabbits, primates and canines. Described a new canid, Canis lupus ambronensis.

O. Legasa, A.D.Buscalioni & Z.Gasparini: The serrated teeth of Sebecus and the iberoccitanian crocodile. A morphological and ultrastructural comparison. 127-144.

Abstract:- The morphology and enamel ultrastructure of serrated teeth of crocodiles is compared. The sample is composed by isolated teeth attributed to the iberoccitanian form (Eocene of the Duero basin, Spain) and Sebecus (S. ?huilensis and S. icaeorinus, Eocene of Argentine and middle Miocene of Colombia). Quantitative and qualitative characters of the tooth crown and serrations are examined. Exploration of new significant morphological characters of the tooth crown is essayed. In this sense, it has been raised several variables that discern symmetry of the tooth crown, differentiating the larger teeth of Sebecus ?huilensis from the iberoccitanian ones.

Ultrastructural analysis also evidenced a pseudoprismatic organization of the enamel of S. ?huilensis contrasting with the aprismatic pattern of the iberoccitanian crocodile.

Here serrated teeth is defined as those that posses carinae with isolated denticles. An isolated denticle is a discrete morphological unit. This definition excludes teeth with coarse carinae, builded from convergent anastomosed ridges that coming from the ornamentation of the crown enamel.

Functional aspects of the teeth are evaluated considering the microware patterns observed on the isolated denticles.

Ildefonso Armenteros: Síntesis del Paleógeno del borde oriental de la Cuenca de Almazán (Soria): Geología del yacimiento de Mazaterón. 145-156.

Abstract:- This work presents a synthesis of the Palaeogene sedimentation that followed the discontinuity between the Upper Cretaceous and the middle Eocene. A syntectonic discordance developed in the Oligocene. Four carbonate units (with marly muddy intercalations) are recognized alternating with clastic units (conglomerates, sandstones and mudstones). Carbonate and siliceous clasts in this clastic units change laterally and vertically both in amount and composition. The carbonate units are interpreted as having formed in shallow lakes, while the clastic units represent transversal alluvial fan systems and longitudinal braided fluvial systems. The clastic/carbonate alternations were controlled by uplit phases of the adjacent Iberian Range. The outstanding fossil site of Mazaterón (rich in vertebrates) demonstrates that the Palaeogene record began in this area at the end of the middle Eocene.

M.Á.Cuesta & E. Jiménez Fuentes: Síntesis del Paleógeno del borde oriental de la Cuenca de Almazán (Soria): Vertebrados de Mazaterón. 157-

Abstract:- In the present paper paleontologic data on Mazaterón site (upper Rhenanian) (Soria province, Castilla-León, Spain) are summarized. Faunal list includes: Fishes (Bagridae), Turtles (Pelomedusidae, Trionychidae, Testudinidae), Crocodíles (Alligatoridae, Baurusuchidae, Family indet.), Saurians, Primates (Adapidae, Omomyidae), Rodents (Pseudosciuridae, Theridomyidae), Creodonts (Hyaenodontidae), Perissodáctyls (Pachynolophidae, Palaeotheriidae) and Artiodáctyls (Dacrytheriidae, Xiphodontidae, Anoplotheriidae).