54 research outputs found
MamĂferos y la colonizaciĂłn de islas
En el MediterrĂĄneo hay muchas islas, y en varias de ellas se han encontrado faunas de mamĂferos fĂłsiles bien distintos de todo lo que se conoce en el continente. AdemĂĄs, en muchos casos son faunas con muy pocas especies. AquĂ intentaremos explicar las caracterĂsticas de estas faunas y los mecanismos de la colonizaciĂłn de las islas.En el Mediterrani hi ha moltes illes, i en diverses dâelles sâhan trobat faunes de mamĂfers fĂČssils ben distints de tot allĂČ que es coneix en el continent. A mĂ©s a mĂ©s, en molts casos sĂłn faunes amb molt poques espĂšcies. AcĂ intentarem explicar les caracterĂstiques de aquestes faunes i els mecanismes de colonitzaciĂł de les illes.Many islands in the Mediterranean have yielded fossil mammal faunas that are very different from those of the mainland. Furthermore, they are often characterized by the small number of species. Here we will try to explain these differences and the mechanisms of colonization of islands
A new species of Vasseuromys (Gliridae, Mammalia) from the Upper Oligocene of the Ebro Basin (Spain)
In this paper, a new species of Vasseuromys,
V. bergasensis sp. nov., from the locality of Bergasa (Ebro
Basin, Spain), is described. Bergasa contains a fauna
belonging to the Late Oligocene (zone MP30), composedâ
among other speciesâof Issiodoromys pseudanaema and
Rhodanomys transiens. The main diagnostic features of
V. bergasensis sp. nov. are the presence of a long centrolophid
(fused or not to the mesoconid) in the lower molars, a large
reduction in thenumber and length of extra ridges in the upper
and lower molars, the absence of extra ridges between metalophid
and centrolophid and between centrolophid and
mesolophid, and the absence of the metatrope in more
than half the specimens of the upper teeth M1 and M2.
V. bergasensis sp. nov. is similar in size to V. elegans and
smaller than the other members of the genus. The age and
simple dental pattern of the new species of Vasseuromys
allow us to hypothesize about relationships within the genus
Rodents and insectivores from the Lower Miocene (Agenian and Ramblian) of the Tudela Formation (Ebro Basin, Spain)
The rodent and insectivore faunas of Agenian and Ramblian age from the Tudela Formation (Ebro Basin, Spain) are described. Four of the localities (CH1, CA1, CC1 and CA2) contain rodent remains of Agenian age (local zone Y), and three (CA3, CA3B and CA4) of Ramblian age (local zones Z and A). Typical Agenian taxa include Armantomys cf. bijmai (CH1), Eucricetodon cf. gerandianus (CA1), Peridyromys turbatus, Simplomys aff. aljaphi and Armantomys daamsi (CA2) and Eucricetodon aff. aquitanicus(CC1). On the other hand, some typical Ramblian taxa are Armantomys cf. parsani (CA3), Ligerimys aff. magnus and Pseudotheridomys sp. (CA4) and Prodryomys cf. brailloni (CA3B). The faunas are characterized by the richness and diversity of the glirids. The presence of the glirid Altomiramys in CA4 represents the first Upper Ramblian record of this taxon.En este trabajo se describen las faunas de roedores e insectĂvoros de edad Ageniense y Rambliense de la FormaciĂłn Tudela (Cuenca del Ebro, España). Cuatro de las localidades (CH1, CA1, CC1 y CA2) contienen restos de edad Ageniense (zona local Y), y tres (CA3, CA3B y CA4) de edad Rambliense (zonas locales Z y A). Entre otras, las faunas Agenienses incluyen a Armantomys cf. bijmai (CH1), Eucricetodon cf. gerandianus (CA1), Peridyromys turbatus, Simplomys aff. aljaphi y Armantomys daamsi (CA2) y Eucricetodon aff. aquitanicus (CC1). Del mismo modo, entre las faunas Ramblienses se incluye a Armantomys cf. parsani (CA3), Ligerimys aff. magnus y Pseudotheridomys sp. (CA4) y Prodryomys cf. brailloni (CA3B). Las faunas encontradas en estos yacimientos se caracterizan por la riqueza y diversidad de glĂridos. La presencia del glĂrido Altomiramys en CA4, representa el primer registro de este taxon en el Rambliense superior
The Aragonian type area revisited; comments on paleontology and stratigraphy
In a recent study of van der Meulen and coauthors, the fossil rodents Fahlbuschia, Pseudofahlbuschia and Renzimys from the Aragonian type area (Calatayud Basin, Spain) were synonimized with Democricetodon. On the basis of the relative chronology provided by Daams and coauthors in an earlier study, these authors construed two evolutionary lineages, distinguished by size. One of these lineages contains Fahlbuschia koenigswaldi (Freudenthal, 1963) and the other one Democricetodon moralesi van der Meulen et al., 2004 but, in view of their great similarity, we consider D. moralesi to be a synonym of F. koenigswaldi. The relative stratigraphic position of some fossil mammal localities is difficult to establish in the Aragonian type area because it is affected by folds and faults. Early studies of Daams and Freudenthal subdivided the local zone D into D1, D2, D3 and gave a scheme of the stratigraphy in which the fossiliferous locality Valdemoros 1A is considered to be older than Valdemoros 3B. But Daams and coauthors came to the opposite interpretation in a later study, and divided zone D in Da, Db, Dc, Dd. But, new field data presented here enforce the original interpretation in which Valdemoros 1A is older than Valdemoros 3B. This leads to the conclusion that the division of local zone D into Da to Dd has to be discarded, and substituted by the formerly proposed zonation D1-D3
La mention la plus méridionale de Castoridae (Mammalia, Rodentia) fossiles en Europe
Le but de ce travail est de rĂ©vĂ©ler de nouvelles informations sur le castor fossile mal connu Dipoides problematicus (Schlosser, 1902). Des restes de cette espĂšce ont Ă©tĂ© trouvĂ©s dans plusieurs gisements proches de la limite Mio-PliocĂšne du Bassin de Grenade (sud de lâEspagne). Pendant cette pĂ©riode les castors sont trĂšs rares dans le sud de lâEspagne, mais abondants dans la rĂ©gion de Teruel, situĂ©e plus au nord. Ătant donnĂ© leurs exigences Ă©cologiques, leur prĂ©sence dans le Bassin de Grenade et leur absence dans dâautres bassins du sud de lâEspagne revĂȘtent une importance palĂ©obiogĂ©ographique et palĂ©oĂ©cologique.This paper tries to amplify the information about the poorly known fossil beaver Dipoides problematicus (Schlosser, 1902). This species has been found in several localities near the Mio-Pliocene boundary of the Granada Basin (southern Spain). During that time span, beavers are very scarce in southern Spain, but abundant in the Teruel region (northern Spain). Since they have specific ecological preferences, their presence in the Granada Basin and their absence in other southern Spanish basins have paleobiogeographical and paleoecological consequences.</p
PrĂ©sence de dents pharyngiennes de carpe, <i>Cyprinus</i> Linnaeus (Teleostei, Cyprinidae) dans le MiocĂšne moyen et supĂ©rieur dâAndalousie (Sud de lâEspagne) : une surprenante rĂ©partition palĂ©obiogĂ©ographique disjointe
Trois dents pharyngiennes de carpe, Cyprinus LinnĂ©, ont Ă©tĂ© dĂ©couvertes en lavant et tamisant du sĂ©diment dans le MiocĂšne moyen et supĂ©rieur dâAndalousie (Espagne). Leur examen a montrĂ© quâelles sont trĂšs semblables Ă celles de la carpe actuelle, Cyprinus carpio LinnĂ©, si bien quâil ne serait pas impossible quâelles appartiennent Ă cette espĂšce. Leur prĂ©sence dans le Sud de lâEspagne Ă cette pĂ©riode est surprenante, parce que lâexistence de restes du genre Cyprinus est inconnue avant le PlĂ©istocĂšne dans les pays situĂ©s Ă lâouest de lâUkraine, car aucun squelette en connexion, ou aucun reste osseux de carpe nâa jamais Ă©tĂ© identifiĂ© dans les nombreux gisements mio-pliocĂšnes dâEurope centrale et occidentale.Three pharyngeal teeth of carp, Cyprinus Linnaeus, were found when washing and screening sediment in the Middle and Upper Miocene of Andalusia (Spain). Their examination has shown that they look very similar to those of the recent carp, Cyprinus carpio Linnaeus, so that it would not be impossible that they belong to this species. Their presence in southern Spain at that time is surprising because Cyprinus remains are unknown before the Pleistocene in the countries westward of Ukraine, as no articulated skeleton or bony fragment of this genus has ever been identified in the many Mio-Pliocene localities investigated throughout central and western Europe.</p
<i>Blarinoides aliciae</i> sp. nov., un nouveau Soricidae (Mammalia, Lipotyphla) du PliocĂšne dâEspagne
Une nouvelle espĂšce de Blarinoides (Soricidae, Mammalia), Blarinoides aliciae, est dĂ©crite du PliocĂšne de Tollo de Chiclana (dĂ©pression de Guadix, Espagne sud-orientale). Elle est notablement plus petite que la seule espĂšce du genre connue jusquâĂ maintenant, B. mariae. B. aliciae est documentĂ©e dans plusieurs autres gisements espagnols, mais lâĂ©chantillon de Tollo de Chiclana-3 est le plus abondant. B. aliciae dĂ©montre lâexistence simultanĂ©e de deux espĂšces de Blarinoides en Europe au PliocĂšne : une premiĂšre, de grande taille, en Europe centrale et orientale, et une seconde, plus petite, dans la pĂ©ninsule IbĂ©rique.A new species of Blarinoides (Soricidae, Mammalia), Blarinoides aliciae, is described from the Pliocene of Tollo de Chiclana (Guadix Basin, southeastern Spain). It is notably smaller than the single species of this genus known until now, B. mariae. B. aliciae is recorded from several other Spanish localities, but the sample from Tollo de Chiclana-3 is the most numerous. B. aliciae proves the simultaneous existence of two different species of Blarinoides in Europe during the Pliocene: one of large size in central and eastern Europe, and another one of small size in Iberia.</p
<i>Eomyops noeliae</i> sp. nov., un nouveau Eomyidae (Mammalia, Rodentia) de lâAragonien de lâEspagne
Une nouvelle espĂšce dâ Eomyops, Eomyops noeliae, est dĂ©crite de la localitĂ© MT-20A (Morteral section, bassin du Magro, Est de lâEspagne). Cette espĂšce a des dimensions intermĂ©diaires entre le grand Ă©omiidĂ©, E. hebeiseni , et le groupe dâespĂšces de petite taille, constituĂ© par E. catalaunicus, E. bodvanus et E. oppligeri. LâĂąge de cette espĂšce est Aragonien infĂ©rieur. MT-20A est localisĂ© entre des dĂ©pĂŽts qui contiennent Megacricetodon primitivus et Megacricetodon collongensis. La morphologie dâ E. noeliae sp. nov. est diffĂ©rente du reste des espĂšces du genre, due Ă une rĂ©duction importante de lâanterolophe lingual des M 1,2,3 et de lâantĂ©rolophide labial de la M 3 . Lâincisive infĂ©rieure de cette nouvelle espĂšce montre deux rides parallĂšles tout au long de lâĂ©mail, comme chez lâespĂšce type, E. catalaunicus. Ce caractĂšre est trĂšs important pour la distinction entre Eomyops et le genre amĂ©ricain, Leptodontomys.A new species of Eomyops, Eomyops noeliae, is described. from the locality MT-20A (Morteral section, Magro basin, eastern Spain). It is intermediate in size between the large eomiid, E. hebeiseni, and the small species of the group E. catalaunicus, E. bodvanus and E. oppligeri. The age range is Lower Aragonian. MT-20A is located between deposits that contain Megacricetodon primitivus and M. collongensis. Morphologically, E. noeliae sp. nov. is clearly different from the rest of species of the genus, due to an important reduction of the lingual anteroloph of M 1,2,3 and the labial anterolophid of M 3. The lower incisor shows two parallel ridges along the enamel like the type species of the genus, E. catalaunicus. This character is basic for the distinction between Eomyops and the North American genus Leptodontomys.</p
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