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1.
A diverse, new lizard assemblage from the early Oligocene of Belgium is described. The Boutersem railway local fauna is the most species‐rich lizard assemblage yet reported from the European early Oligocene. Four lizard taxa are present: Lacertidae, Anguidae, Scincoidea and Platynota. One new species is described, Folisaurus boutersemensis sp. nov . This fauna provides new insight into the profound turnover that took place during the Eocene/Oligocene boundary in Europe. The new fauna confirms a marked decrease in diversity across the Eocene/Oligocene boundary. Two groups encountered in the European late Eocene became extinct (Iguanidae*, Glyptosaurinae). Estimates of species‐level extinctions range up to 80%. These estimates include members of virtually all the families present in the late Eocene. The relative importance of climate change and biotic interactions in controlling this pattern is discussed, and negative interactions between lizards and new carnivorous mammals are favoured. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 148–170.  相似文献   

2.
The oldest freshwater neritiliid, Neritilia bisinuata , is described from the Middle Eocene of the Loire Basin. Another European species, N. neritinoides , ranging from the Lower Oligocene to Lower Miocene (Upper Burdigalian) is recognized; its habitat appears to have been freshwater, but very close to the sea. Two new marine neritiliid species from the Aquitaine Basin are described: Bourdieria favia sp. nov. from the Upper Oligocene and Pisulinella aucoini  sp. nov. from the Lower Miocene. A third undescribed species from the Lower Miocene is referred to the same family and related to Pisulinella . The Oligocene species has a strong spiral sculpture, a character completely absent in previously known neritiliid species. The genus Agapilia , founded on juvenile N. neritinoides and adult Vitta picta , appears to be a junior synonym of the genus Vitta. The associated occurrence of shells of the families Neritiliidae, Neritopsidae and Pickworthiidae (well-known inhabitants of Indo-West Pacific submarine caves) at Peyrère suggest the first occurrence of a characteristic assemblage of dark submarine caves during the Oligocene. Both factorial analysis and relative abundance show that at Peyrère these families are associated with other cryptic fossils (various gastropods, bivalves, Brachiopoda, corals, Annelida). However, there are indications of other submarine cave assemblages in various Cenozoic deposits from the Palaeocene to the middle Miocene.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 447–467.  相似文献   

3.
Fossil leaves and a branch with a leaf and a pod attached have been discovered from Ningming County, Guangxi Autonomous Region, China, and are described as Bauhinia larsenii sp. nov. (Leguminosae: Cercideae). The strata from which the Bauhinia fossils were collected, namely the Ningming Formation, were dated as Late Eocene–Oligocene based on a combination of pollen, fauna and flora. The affinity of the new species to Bauhinia section Micralvesia subsection Viridescentes species is also discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 437–440.  相似文献   

4.
A new barbourofelid species, Prosansanosmilus eggeri , is described from the Middle Miocene (MN 5) locality of Sandelzhausen, Germany. It differs from all other European barbourofelid species in being smaller and showing a more plesiomorphic morphology, especially in the relatively less developed sabretooth adaptations, low accessory cusps on the premolars, and the remnant of a very small talonid on the carnassial. The species is, however, stratigraphically later than the more apomorphic P. peregrinus, which is known from MN 4 of Germany and France. A phylogenetic analysis based on dental characters of early nimravids, barbourofelids and felids supports previous results on skull morphology of Barbourofelis that Barbourofelinae is not closely related to the Late Eocene and Oligocene Nimravinae. Instead, both subfamilies should be treated as separate families, with the Barbourofelidae closely related to the Felidae. The Barbourofelidae differ from the Felidae as well as from the Nimravidae s.s ., particularly in the unique morphology of their basicranium. They presumably originated in Africa; P. eggeri sp. nov. is interpreted as part of a Miocene immigration of African faunal elements into Europe that took place at the beginning of MN 5. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 43−61.  相似文献   

5.
Lacustrine interbeds of a volcaniclastic succession that crops out extensively in north-western Patagonia yielded impressions of articulated, nearly complete, frogs of different ontogenetic stages including tadpoles. The stratigraphic position of the fossil bearing beds in this sequence and evaluation of palaeofloristic data against the record of climatic change in southern high latitudes support a middle Eocene – early Oligocene age for the frogs. These frogs are described as a new genus and species that resembles the late Palaeocene ' Xenopus' romeri from Brazil, and differs from the middle Eocene S. pascuali from Patagonia, in the relatively wide and short braincase and fused first two presacral vertebrae. However, unlike ' X. '  romeri , the nasals are paired and bear short, but distinct, rostral processes. A parsimony analysis based on 49 adult osteological characters demonstrates that these South American fossil pipids are closely related to xenopodines, restricted to the African continent today, although their interrelationships remain poorly resolved. Interpretation of the ontogenetic stages exemplified by the fossil specimens suggests a developmental pattern more similar to that of extant xenopodines than to the ontogeny of more distant pipoid relatives. Moreover, the similarity between these fossil larvae and those of Xenopus and Silurana strongly suggests similar habits. Many of these larval features may be considered as caenogenetic, i.e. specializations of the tadpoles as obligate, microphagous suspension feeders.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 439-476.  相似文献   

6.
7.
Caviomorphs (South American hystricognaths) are recorded in the continent since the middle Eocene. The middle Eocene–early Oligocene is considered a key moment for their evolutionary history because by the early Oligocene they were differentiated into four superfamilies: Octodontoidea, Cavioidea, Chinchilloidea and Erethizontoidea. Due to their generalized dental patterns and abundance in the fossil record, Octodontoidea are interesting for analysing the origin and early history of caviomorphs. The phylogenetic relationships of the earliest octodontoids are studied herein. Results confirmed a basal caviomorph diversification in the middle Eocene (c. 45 Mya), with one lineage leading to Pan‐Octodontoidea, and another leading to Erethizontoidea, Cavioidea and Chinchilloidea, which is not in accordance with analyses based on molecular data. Three major radiations were identified: the first one (late Eocene?/early Oligocene?) occurred in low latitudes with the differentiation of Pan‐Octodontoidea and the earliest crown‐Octodontoidea. The second radiation (late Oligocene) was a large‐scale South American event; in the southernmost part of the continent it is recognized as the first Patagonian octodontoid radiation, which provided the characteristic high morphological disparity of the superfamily. The third radiation (late Miocene) is characterized by the replacement of ‘old’ by ‘modern’ octodontoids; the nature of this third event needs to be study in a broader taxonomic context. © 2015 The Linnean Society of London  相似文献   

8.
The osteology of the early Eocene (about 50 mya) avian taxon Pseudasturidae Mayr, 1998 is revised and its phylogenetic affinities are analysed. Members of the Pseudasturidae are known from abundant and excellently preserved skeletal material, both complete skeletons on slabs as well as isolated, three-dimensional bones. Although this taxon is thus among the best represented of all small early Tertiary birds, its systematic affinities were unknown so far. Derived osteological characters which are visible in newly recognized specimens from the Lower Eocene London Clay of England most convincingly support classification of the Pseudasturidae into the Psittaciformes (parrots). Both, in overall morphology and in terms of derived characters, the tarsometatarsus of the Pseudasturidae closely resembles that of the Eocene Quercypsittidae, which were assigned to the Psittaciformes by Mourer-Chauviré (1992 ). The Pseudasturidae are considered to be stem-group representatives of the Psittaciformes and the sister taxon of all other known psittaciform birds. The Eocene taxon lacks the specialized bill morphology of crown-group Psittaciformes of the Psittacidae. Several other osteological differences between the Pseudasturidae and the Psittacidae probably are also functionally correlated with the specialized feeding technique of the latter.  © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society , 2002, 136 , 715–729.  相似文献   

9.
The first well-preserved, partial associated skeleton of Anoplotherium latipes , with critical details of tibia, femur, ulna and cervical vertebrae, is described from the UK earliest Oligocene. Anoplotherium and related genera are interpreted as facultatively bipedal, extended-limb, high browsers, based especially on the following: pelvis with flared ilia and long pubic symphysis; medially bowed tibiae shorter than femora; trunk vertebrae enlarging caudally; extensive attachment for supraspinous and deltoid muscles for raising the forelimbs; long muscular tail for balance; and large hind foot processes for attachment of suspensory ligaments. Although overall most like extinct ground sloths among bipedal browsers, Anoplotherium is unique in combining long muscular tail, hooves instead of claws and relatively short forelimbs. Primitive retention of the long tail facilitated an erect stance without need for the long, clawed forelimb support evolved by chalicotheres. Emphasis was instead on strengthening support by the hind-quarters. With only toe-number differences, A. latipes and A. commune may have been sexual dimorphs. The large Anoplotherium species would have been able to browse 2–3 m above the ground with no competition from other contemporaneous European terrestrial mammals. Bipedal browsing is an adaptation previously unrecognized in European Eocene communities.  © 2007 Natural History Museum. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 609–659.  相似文献   

10.
Approximately 1.7 kbp of mitochondrial DNA were sequenced from 29 individuals assignable to 11 Uromastyx species or subspecies and two other agamids. U. ocellata and U. ornata had an insertion between the glutamine and isoleucine tRNA genes, which could be folded into a stable stem-and-loop structure, and the insertion for U. ornata additionally retained a sequence similar to the glutamine tRNA gene. This corroborates the role of tandem duplication in reshaping mitochondrial gene arrangements, and supports the idea that the origin of light-strand replication could be relocated within mitochondrial genomes. Molecular phylogeny from different tree-building methods consistently placed African and Arabian taxa in mutually monophyletic groups, excluding U. hardwickii inhabiting India and Pakistan. Unlike previous studies based on morphology , U. macfadyeni did not cluster with morphologically similar Arabian taxa, suggesting convergent evolution to be responsible for the morphological similarities. Divergence times estimated among the Uromastyx taxa, together with geological and palaeontological evidence, suggest that the Uromastyx agamids originated from Central Asia during the Eocene and colonized Africa after its connection with Eurasia in the early Miocene. Their radiation may have been facilitated by repeated aridification of North Africa since the middle Miocene, and geological events such as the expansion of the Red Sea and the East African Rift Valley.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 247–260.  相似文献   

11.
With highly conserved morphology throughout the family, a tropical distribution, and no close living relatives, the trogons (Aves: Trogonidae) pose a difficult problem for systematists. Disjunct tropical distributions are often attributed to Gondwanan vicariance, but the fossil record for trogons is mostly from the Tertiary of Europe. This study examined support for the basal relationships among trogons using a combination of nuclear (RAG-1) and mitochondrial (ND2) DNA sequence data. Although some nodes could not be resolved with significant support, there is strong support for the basal position of three New World genera ( Pharomachrus , Euptilotis , and Priotelus ). This phylogenetic hypothesis differs markedly from previous studies of trogon relationships and taxonomic treatments. Biogeographically, it implies an origin and early vicariance events for the crown clade in the New World. Molecular divergence estimates place all of the basal nodes of the trogon phylogeny in the Oligocene, precluding a Gondwanan origin for modern trogons.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 725–738.  相似文献   

12.
13.
Falseryx neervelpensis sp. nov. (Booid-grade, 'Tropidophiidae') from the earliest Oligocene (MP 21) of Belgium is described on the basis of vertebrae coming from all major portions of the vertebral column. In its peculiar caudal osteology, the snake approaches the unique morphological pattern characteristic of the living Neotropical Tropidophiinae. This is the first time such a complete and informative vertebral column of a dwarf boa has been described. The genus Falseryx was absent from Western Europe in younger parts of the Oligocene, but reappeared at the end of the Early Miocene. This dispersal pattern provides additional evidence that in most phases of the Oligocene and Early Miocene Western European snake faunas were effectively isolated from possible influences from the East.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 393–406.  相似文献   

14.
A new genus and species of osteoglossomorph fish is described from the Eocene Mahenge site in north central Tanzania. The new species is sympatric with the previously described osteoglossomorph † Singida jacksonoides , but is easily distinguished from it by the presence in the new species of teeth on the jaws and entopterygoid. The new species shares characters with the Heterotidinae, such as the two arms of the preopercle being of similar length and the posterior end of the maxilla lying on the dentary, and other characters with the Osteoglossinae (including † Phareodus ), for example the enlarged pectoral fin ray and the shape of the opercular bone. New specimens of † S. jacksonoides also have been recovered from the site, providing more information on the osteology of this fish. The relationships of these two Mahenge osteoglossomorphs are assessed, with both fishes placed within the Osteoglossidae, but of uncertain position in the family. Addition of the new species to previous cladistic data sets, and the revised information for † S. jacksonoides , causes the subfamily Osteoglossinae to be nonmonophyletic.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 144 , 213–228.  相似文献   

15.
A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.  相似文献   

16.
Small diameter pyritized axes, commonly referred to as 'twigs', of fossil platanaceous wood are described from the Lower Eocene London Clay Formation of south-east England. These twigs are characterized by solitary vessels with scalariform perforation plates, opposite intervessel pits, and tall, multiseriate rays that dilate in the phloem region. The wood anatomy supports close relationship to members of extant Platanaceae and the material is placed in the organ genus Plataninium Unger erected for fossil woods with close anatomical similarity to Platanus L. This material supplements the fossil record of platanaceous type wood from the Eocene London Clay and documents the first record of Plataninium decipiens Brett in the twig flora.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 181–191.  相似文献   

17.
The structure of the stomatal apparatus of the leaf of Lycopodium japonicum Thumb was studied using epidermal macerations, sections and scanning electron microscopy. The stomatal apparatus of L. japonicum consists of two large guard cells and pore, and is anomocytic. Based on light microscopy, the impression from epidermal macerations that there were two small guard cells surrounded by two, large, similarly shaped, subsidiary cells (paracytic) derives from a pronounced elliptical cuticular ledge on the surface of the guard cells surrounding a thickened circumporal area. A similar appearance is characteristic of cuticle preparations of the Devonian lycophyte Drepanophycus spinaeformis Göppert. We therefore conclude, as did W.H. Lang over 70 years ago, that the stomata of the early lycophyte were also anomocytic, as were those of a second species of Drepanophycus , D. qujingensis Li & Edwards.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 209–216.  相似文献   

18.
A giant rhinocerotoid is described for the first time south of the Black Sea, in Turkey. The single specimen, a fragmentary radius referred to Paraceratherium sp., originates from conglomerates nearby at Gözükizilli, in the Çankiri–Çorum Tertiary basin. These layers correspond to the Lower member of the Kizilirmak Formation. The same locality (Gözükizilli-2) yields also the small rhinocerotid Protaceratherium sp., cf. P. albigense (Roman, 1912). Three other mammal localities (Gözükizilli-1, in the Lower Member of the formation, with several rodent species; Tepe 641 and Kizilirmak, in the Upper Member, with a diversified micro- and macro-mammal fauna) allow us to refer the Kizilirmak Formation as a whole to the Late Oligocene. All the observed taxa have strong Asian and/or European affinities, which precludes any geographical insulation for this part of Anatolia during the Late Oligocene.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 581–592.  相似文献   

19.
Middle Eocene seagrass compressions occur in the Avon Park Limestone Formation near Gulf Hammock on Florida's west coast. One group of specimens resembles two seagrass species of the hydrocharitaceans, Thalassia and Enhalus , that are living today in tropical and subtropical shallow marine environments. The Eocene plant has a dimorphic rhizome system consisting of a creeping, monopodial, plagiotropic rhizome with small roots and orthotropic laterals (short shoots) that occur in pairs every three to five nodes. Laterals bifurcate and produce glabrous eligulate leaves in an alternate and distichous arrangement. Foliage leaves have fibrous basal sheaths, blades with parallel venation, perpendicular and oblique cross veins, prominent midrib, and smooth, entire margins. Throughout the plant are numerous brown-coloured tanniferous dots and deposits of small calcium oxalate crystals. Based on features of these non-reproductive structures, the Florida Eocene seagrass is recognized as a new genus and species Thalassites parkavonensis in the Hydrocharitaceae.   © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 19–30.  相似文献   

20.
Selaginella hainanensis X.C.Zhang & Noot. sp. nov. , a new species from Hainan Island, South China, is described and illustrated. Diagnostic notes and a key to the species distributed in Hainan are also provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 323–327.  相似文献   

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