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1.
The fossil Desmaninae (water-moles) from the Pliocene continental deposits of Tollo de Chiclana (Guadix Basin, Southern Spain) are described. A new species, Archaeodesmana elvirae, is defined from the locality of Tollo de Chiclana-1 (upper Ruscinian). This species is characterized by relatively small canines and premolars (except the P4) and large P4 and molars, besides several morphological features. The presence of Archaeodesmana brailloni is reported from the locality of Tollo de Chiclana-1B (uppermost Ruscinian). A small sample assigned to the genus Archaeodesmana is described from the lower Villafranchian site of Tollo de Chiclana-3, which cannot be determined at the specific level. The phylogenetic relationships between the different species of Archaeodesmana are reconsidered in the light of the recent findings, which support the idea of a more complex phylogeny than previously proposed for this genus. The populations from the Guadix Basin, previously assigned to Dibolia dekkersi (= Archaeodesmana getica), are here considered to belong to a different (unnamed) species, which is the ancestor of A. elvirae. On the other hand, the new species A. elvirae is proposed as the ancestor of A. brailloni.  相似文献   

2.
Several new fossiliferous Pliocene localities have been identified in the continental deposits of the area of Tollo de Chiclana (Guadix Basin, SE Spain), that have yielded a rich rodent and insectivore fauna. In this paper, we study the Arvicolidae from these localities. Remains adscribed to the genera Dolomys, Mimomys and Kislangia have been found, which are very interesting from a biostratigraphical point of view.  相似文献   

3.
There are a total of 16 fossil cercopithecid specimens, representing at least 10 individuals, from the Chiwondo Beds of northern Malawi. The majority of this material is derived from the Middle Pliocene Unit 3A, but one specimen is from the Early Pliocene Unit 2. This latter specimen is from a papionin of indeterminate genus similar in size to Parapapio ado and Pliopapio alemui. Among the specimens from Unit 3A, two species can be diagnosed: an indeterminate species of Theropithecus, and a species of Parapapio similar in dental size to P. broomi. Neither of the genera from Unit 3A are exclusive to either East Africa or South Africa. Their relative abundances, however, are more similar to Middle Pliocene South African sites where Parapapio is the most common primate genus, and Theropithecus is comparatively rare. This is in contrast to similarly-aged East African sites where Theropithecus is by far the most abundant genus.  相似文献   

4.
Apocricetus Freudenthal et al. (Treballs del Museu de Geologia de Barcelona 7: 11–93, 1998) is a medium to large Cricetinae, practically without mesolophids in the m1 and m2, with long third molars; anterior and posterior protolophule are present and the posterior metalophule is reduced or absent. Apocricetus barrierei (Mein and Michaux Comptes Rendus Academie de Sciences de Paris D 270: 2780–2783, 1970) was defined on the basis of three specimens from the French locality Chabrier. Apart from this site, several French and Spanish localities of Early Pliocene age contain remains of this species. Despite this extra material, the species is poorly characterized, and none of the localities contains material of all six dental elements. In this paper, two new assemblages from La Bullana 2B and La Bullana 3 (Cabriel Basin, Spain) are described. The rich assemblage from La Bullana 2B provides a better insight in the metrical and morphological variability of this species.  相似文献   

5.
《Comptes Rendus Palevol》2008,7(8):571-581
The fossil vertebrate bearing locality Kossom Bougoudi (KB) is situated in the Djurab desert (Chad, Africa), 600 km north-east of N’djamena. It has yielded about 1250 specimens with many mammalian remains, principally artiodactyls. Its geologic age has been estimated to be about 5 Ma by biochronologic estimation and about 5.3 Ma by radiometric studies on cosmogenic nuclides of beryllium (authigenic 10B/9B). The carnivoran fauna contains few specimens which belong to five different families. All the taxa were unknown in central Africa. A large lutrine is close to Sivaonyx but different from known species of the genus. Another large lutrine is similar by its size to a species described from the Middle Pliocene of Uganda. An edentulous mandible of a small machairodont cat resembles a small species of Dinofelis, while a distal humerus indicates the presence of a larger member of the same genus. A hunting hyaenid is also much like the European species. An unidentified canid reaches the size of the recent Canis aureus and an isolated calcaneum matches that of the large extant viverrid. This small fauna allows a first look at the guild of the carnivorans at the Latest Miocene–Pliocene boundary in Central Africa and is a milestone between North African, East African and South African carnivore faunas.  相似文献   

6.
A revision of the Pliocene representatives of the Ilyocyprididae genera Ilyocypris Brady and Norman, 1889, and Qinghaicypris Huang, 1979, obtained from lacustrine sediments of the Villarroya section (La Rioja, N. Spain) is presented in this work. Based on carapace morphology and morphometrics, the occurrence in Europe of the genus Qinghaicypris is discussed. This genus is represented in this material by a new species, Qinghaicypris riojensis nov. sp., which is described herein. The occurrence of Ilyocypris and Qinghaicypris within the lacustrine series of Villarroya is analysed in relation to the hydrological evolution of the water bodies, which were very likely climatically driven. Palaeoecological as well as palaeobiogeographical interest of those genera is pointed out in the context of the aquatorium that spread over big areas of Europe during the Pliocene.  相似文献   

7.
Twenty three echinoid species are described and illustrated from the Pliocene of the area north of Mersa Alam, Red Sea coast of Egypt. Two new speciesSchizaster (Paraster) ashrafi andBrissus shaimaae, and one new subspeciesMaretia planulata abbassi, are described. Six species are recorded here for the first time from the Pliocene of the Red Sea:Eucidaris metularia (LAMARCK), {ITEchinoneus cyclostomus} LESKE,Clypeaster suffarcinatus DUNCAN & SLADEN, C.fervens KOEHLER, C. {ITtelurus} CLARK, andLaganum depressum delicatum MAZZETTI. A discussion is given of the Miocene - Pliocene boundary, the age of the area studied is referred to the early - late Pliocene.  相似文献   

8.
Toll-like receptors (TLRs) are best characterized for their roles in mediating dorsoventral patterning and the innate immune response. However, recent studies indicate that TLRs are also involved in regulating neuronal growth and development. Here, we demonstrate that the TLR Tollo positively regulates growth of the Drosophila melanogaster larval neuromuscular junction (NMJ). Tollo mutants exhibited NMJ undergrowth, whereas increased expression of Tollo led to NMJ overgrowth. Tollo expression in the motoneuron was both necessary and sufficient for regulating NMJ growth. Dominant genetic interactions together with altered levels of phosphorylated c-Jun N-terminal kinase (JNK) and puc-lacZ expression revealed that Tollo signals through the JNK pathway at the NMJ. Genetic interactions also revealed that the neurotrophin Spätzle3 (Spz3) is a likely Tollo ligand. Spz3 expression in muscle and proteolytic activation via the Easter protease was necessary and sufficient to promote NMJ growth. These results demonstrate the existence of a novel neurotrophin signaling pathway that is required for synaptic development in Drosophila.  相似文献   

9.
《Palaeoworld》2014,23(3-4):370-382
Two fossil leaves identified as Castanopsis presclerophylla n. sp. collected from a diatomite bed in the upper Pliocene (3.3–2.8 Ma) in Tengchong County, Yunnan Province, Southwest China, are characterized by elliptic laminar shapes with acuminate apex, convex base, simple trichome bases and cyclocytic stomata. The cuticles of extant leaves from six selected Castanopsis species that are similar to the Pliocene fossil leaves in laminar shape were examined in detail for the comparison. Based on the analysis of leaf architecture and cuticular characteristics, the present fossil leaves most closely resemble the extant leaves of Castanopsis sclerophylla (Lindl.) Schott., which prefers a subtropical climate. The published fossil records of Castanopsis also indicate that it was once widely distributed in North America, Europe and Asia before the Pliocene, and then rapidly retreated to the East and Southeast Asia as a result of the Pleistocene glaciation.  相似文献   

10.
The fossil mammal localities of the Axios Valley (Macedonia, Greece) yielded a rich collection of Mesopithecus remains, which were first described at the beginning of the 1990s. The late Turolian Dytiko localities include several specimens of Mesopithecus, which were originally separated in two size-related forms: the relatively larger-sized M. cf. or aff. pentelicus, and the relatively smaller-sized M. cf. monspessulanus. However, some Dytiko specimens were only partially described, or remained even undescribed because the cranium either was still in connection with the mandible or was markedly deformed. Later, careful cleaning of the materials and their revision based on larger comparative samples indicate that they represent two distinct species: the relatively larger-sized specimens belong to M. pentelicus, while the relatively smaller-sized ones to M. monspessulanus. The Dytiko M. pentelicus has slightly smaller dental dimensions compared to M. pentelicus from Pikermi, indicating a possible trend for size decrease. The Dytiko M. monspessulanus, although close to the typical form of this species, has somewhat larger dimensions. The semi-terrestrial M. pentelicus disappeared at the end of the Miocene, while some of its populations adapted to the wetter and more woody Pliocene habitats, finally giving origin to M. monspessulanus, whose elbow-joint indicates an arboreal lifestyle. M. monspessulanus was widely distributed in Europe, but its remains are very scarce and are all from the Pliocene. Some questionable indications for the presence of M. monspessulanus in the latest Miocene come from some Italian Messinian sites (Gravitelli, Baccinello V3), but this scenario still needs verification. However, even if its presence in some Italian localities was confirmed, the Dytiko M. monspessulanus nonetheless represents the earliest known occurrence of this species in Europe, as the Dytiko fauna is considered as latest Turolian (pre-Messinian, 7.0–6.0 Ma).  相似文献   

11.
Carnivores from the Late Pliocene site of V?eláre 2 are described and their taxonomy is discussed. The carnivore assemblage includes nine specimens of the families Felidae (Homotherium crenatidens), Ursidae (Ursus minimus), and Ailuridae (Parailurus sp.). The scimitar-toothed cat and ursid are common representatives of the Pliocene European fauna, whereas the lesser panda is probably a new species of Parailurus, which differs from both Pliocene species, P. anglicus and P. hungaricus. As a part of a more or less uniform Pliocene carnivore fauna of the Northern Hemisphere, the V?eláre 2 assemblage represents a forest and (or) open grassland environment.  相似文献   

12.
The six species and three subspecies in the genus Chimarrogale (Soricomorpha: Soricidae) are commonly referred to as Asiatic water shrews. The Chimarrogale are the most widely distributed group of Nectogaline shrews, extending throughout the Oriental region and Japan. Because of the limited numbers of specimens available for study, the phylogenetic relationships and biogeographical history of this genus have not been comprehensively discussed. We used mitochondrial cytochrome b gene sequences to estimate phylogenetic relationships and divergence times among four Chimarrogale species, including all three subspecies of Chimarrogale himalayica. We also conducted a species delimitation analysis and tested two alternative migration scenarios in Asia through species distribution modeling and a reconstruction of the ancestral distribution. Here, we present the first proposed hypothesis regarding the Asiatic water shrew phylogeny and reveal ten putative species within the four recognized species. Distinct phylogenetic statuses of Chimarrogale phaeura, Chimarrogale platycephala, and Chimarrogale styani were confirmed. Chimarrogale himalayica was strongly supported as paraphyletic. We suggest that three subspecies of Chimarrogale himalayica should be reconsidered as distinct species. However, these suggestions must be considered with caution because only a single locus of a mtDNA gene was used. Four additional putative species, possibly distributed in central southwestern China and Taiwan, are currently undescribed; therefore, comprehensive morphological analyses are warranted to test their taxonomic statuses. The estimated molecular divergence times indicated that rapid speciation occurred during the early Pliocene, and current distribution patterns may have been affected by global cooling during the Pliocene/Pleistocene boundary. Reconstruction of the ancestral distribution and species distribution modeling for Asiatic water shrews revealed a low-latitude migration route over which ancestral Chimarrogale migrated from Europe via Central Asia to their current distribution. Our results demonstrated that Asiatic water shrews could have evolved throughout the low-latitude migration route from Europe to East and Southeast Asia.  相似文献   

13.
The enlarged inflorescence bract diagnostic of extant Tilia has an extensive Tertiary fossil record in the Northern Hemisphere. Diversity of bract morphology, and the extent of adnation between peduncle and bract, is reviewed for fossil and extant species of Tilia. An extinct type of bract with an orbicular outline and palmate venation is documented by the fossil species Tilia circularis (Chaney) comb. nov. from the early Oligocene of Oregon and is designated Type A. Living species of the genus have elongate bracts with predominately pinnate venation that are borne in two basic configurations: Type B, with the peduncle fused only to the extreme base of the bract lamina, as in extant Tilia endochrysea Hand.-Mzt. of southern China; and Type C with the peduncle fused medially along the basal one-third of the bract lamina, as in most extant species. Bracts of Type B were widely distributed in the Tertiary of western North America (late Eocene to Miocene) and Europe (early Miocene to Pliocene), while those of Type C are known in the fossil condition only from the middle and late Tertiary of Asia and Pliocene of Europe. The bracts of T. circularis, like those of type B, are borne on relatively long stalks and have the peduncle fused only at the extreme base. The fossil record supports recognition of the following characters as apomorphic in Tilia bract evolution: bracts sessile, peduncle adnate to the upper surface of the bract, and pinnate bract venation.  相似文献   

14.
Prolagus italicus n. sp., a new endemic Pliocene species of peninsular Italy, is described here, adding new details to the knowledge of this widespread and long-lasting ochotonid genus. Several dental morphodimensional characters suggest a close relationship between P. italicus and P. sorbinii (evaporitic and postevaporitic Messinian, central Italy). On the other hand, P. italicus shares with other Plio-Pleistocene Prolagus species of continental Europe a large size and some peculiar characters of dental occlusal surface. Actually, an evolutionary trend can be detected in Plio-Pleistocene species of the genus Prolagus. The value of P. italicus in biochronology is quite consistent, as this species seems to mark MN17 in central Italy. Moreover, some morphodimensional differences between P. italicus populations have been identified: this can help to infer relative chronological positions to the fossil sites in which P. italicus is present. Some morphological characters present in one of the two available P. italicus populations are apparently related to ecological more than to evolutionary factors: this may be a starting point for in-depth palaeoecological studies related to the genus Prolagus. The presence of P. italicus in the Italian peninsula may have prevented the entrance of other species of western European affinity.  相似文献   

15.
The taxonomic and genetic diversity of Cortinarius section Calochroi in one of the most biodiversity-rich regions in Europe, the Iberian Peninsula, was investigated through morphological and phylogenetic methods. This combined methodological approach allowed the identification of 15 known species and one new species, Cortinarius ortegae, which is described here. A dichotomous key is provided for field recognition of Calochroi species inhabiting different Iberian and Balearic Island woodlands. Polymorphism analyses within some studied species showed that the distribution of intraspecific lineages is dependent on geography and, in some cases, tree host. Furthermore, the dating analysis suggested that diversification within Calochroi started in the Pliocene and most of the current genetic diversity originated in the Pleistocene. This temporal scenario supports hypotheses in which climatic oscillations in the Quaternary may have been driving the evolution of this group of ectomycorrhizal fungi.  相似文献   

16.
《Comptes Rendus Palevol》2007,6(5):327-334
Fossil leporids from the Upper Pliocene of the locality of Perrier-Étouaires (Auvergne, France) are here revisited. They were initially attributed to Lepus lacosti by Pomel (1853), and later to the genus Oryctolagus. This material had been neither accurately described nor figured until now. Thus, a lectotype and two paralectotypes have been chosen among the material of the original collection. The diagnostic character of Oryctolagus lacosti is its big size, similar to that of modern hares (Lepus), together with other morphological characters that fit in the variability range of European rabbits (Oryctolagus cuniculus). Fossils of leporids similar to those of Perrier have also been found in several Plio-Pleistocene localities from western Europe.  相似文献   

17.
《Comptes Rendus Palevol》2008,7(8):557-569
New observations on the Late Miocene and Earliest Pliocene mustelids from the Middle Awash of Ethiopia are presented. The Middle Awash study area samples the last six million years of African vertebrate evolutionary history. Its Latest Miocene (Asa Koma Member of the Adu-Asa Formation, 5.54–5.77 Ma) and Earliest Pliocene (Kuseralee and Gawto Members of the Sagantole Formation, 5.2 and 4.85 Ma, respectively) deposits sample a number of large and small carnivore taxa among which mustelids are numerically abundant. Among the known Late Miocene and Early Pliocene mustelid genera, the Middle Awash Late Miocene documents the earliest Mellivora in eastern Africa and its likely first appearance in Africa, a new species of Plesiogulo, and a species of Vishnuonyx. The latter possibly represents the last appearance of this genus in Africa. Torolutra ougandensis is known from both the Late Miocene and Early Pliocene deposits of the Middle Awash. The genus Sivaonyx is represented by at least two species: S. ekecaman and S. aff. S. soriae. Most of the lutrine genera documented in the Middle Awash Late Miocene/Early Pliocene are also documented in contemporaneous sites of eastern Africa. The new observations presented here show that mustelids were more diverse in the Middle Awash Late Miocene and Early Pliocene than previously documented.  相似文献   

18.
Fossil remains of Taxodium from upper Eocene to lower Miocene localities in Germany, the Czech Republic and Russia are investigated to reconsider taxonomic concepts. It is demonstrated that all material belongs to one species which is named Taxodium dubium (Sternberg) Heer emend. Using the whole-plant concept, T. dubium is considered as a synthetic species comprising foliage, seed cones, seeds, and male cones with pollen in situ. Shared identity of T. dubium and the wood morpho-taxon Taxodioxylon taxodii Gothan is assumed. Taxodium dubium underwent evolutionary changes through the Oligocene expressed mainly in changes of the cone scale ornamentation. To designate this intraspecific variation taxonomically two morpho-formae are distinguished: T. dubium forma heerii (Dorofeev) Kunzmann, Kva?ek, Mai et Walther stat. nov. et emend. and T. dubium forma dubium. Simultaneous intraspecific variations in leaf morphology and leaf epidermal anatomy are missing. Taxodium dubium occurs from the late Eocene to late Miocene in the (Atlantic-) Boreal province sensu Mai of Central Europe and from the late Oligocene to late Pliocene in the Transeuropean Paratethys province sensu Mai.  相似文献   

19.
Daniel Pajaud 《Geobios》1976,9(4):481-502
A benthic taphocoenose from the Pliocene I of Aguilas (provinces of Murcia-Almeria, Southern Spain) conseals four Cirripedia (family of BalanidaeLeach): Balanus (Balanus) perforatus angustusGmelin, B. (B.) amphitriteDarwin, B. (Megabalanus) tintinnabulum tintinnabulumLinné and Creusia (Withersia) phryxaPajaud.The study of the last one is especially interestingfrom an ecological point of view. Indeed, all species, well-known in the Creusia-Pyrgoma group are more or less dependent on Anthozoa since Miocene, the cuplike basis of their shell buried on corallites. But not corallites were gathered in the deposits of Aguilas and the morphology of Creusia phryxa leads us to believe a fixation of the shell on a flaccid substratum. From which we may suppose that the host of this Cirriped was perhaps an Actiniaria.  相似文献   

20.
For the first time unequivocal fossil remains of a green toad (Bufo viridis s.l.) are described in the Iberian Peninsula. The fossils come from the Cueva Victoria site, a late Early Pleistocene (ca. 1.1–1.2 Ma) karstic filling in semi-arid southeastern Spain (Murcia region). By extension, other remains from two other Early Pleistocene Spanish localities, Barranco León D (ca. 1.3 Ma) and Almenara-Casablanca 3 (ca. 1.1 Ma), are cautiously attributed to the group B. viridis. The B. viridis group was previously reported with some uncertainty to the west of its current distribution area in Western Europe (Spain and France) in the Pliocene (Bufo cf. viridis) and less probably in the Early Miocene (Bufo aff. viridis). Since no osteological differences have been established between the recently described extant species of B. viridis s.l. (e.g. Bufo balearicus, Bufo siculus, Bufo boulengeri, B. viridis sensu stricto and Bufo variabilis) no precise palaeobiogeographical relationships can be drawn for the Spanish fossils. However, the occurrence of a third species of bufonid toad during the Pleistocene in the South of the Iberian Peninsula raises some interesting ecological questions in relation to the local disappearance of the green toad, which can be hypothetically linked to the intensification of the Pleistocene glacial/interglacial climate dynamic or to probable competition with another toad, Bufo calamita.  相似文献   

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