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1.
The Cova del Rinoceront is the first site in the Iberian Peninsula where the genus Haploidoceros has been documented. This discovery of abundant remains is also its first recorded occurrence in Europe during the Upper Pleistocene. The new fossil record strengthens claims that this genus was widely distributed during the Pleistocene, occupying a longer time span at least until MIS 5. Cranial and post-cranial skeletal remains ascribed to this species were recovered from the uppermost layers of the Cova del Rinoceront. The diagnostic features that allow these remains to be unequivocally assigned to H. mediterraneus, include their cranial morphology and antler shape, comprising two sickle-shaped beams, curving backwards and laterally, and a long frontal basal tine. This paper highlights the problems of deer systematics and identification given the high degree of fragmentation of the genus, their relatively homogeneous morphology, a virtual absence of reliable characters and the overlap of measurements between species.  相似文献   

2.
The article describes part of the Entactinaria radiolarians from a very rich and well-preserved radiolarian assemblage extracted from a lower Tithonian sample (Mue 22) collected from the Mühlheim Member of the Mörnsheim Formation of southern Germany. With a single exception (genus Odoghertites nov. gen.), all other Entactinaria described are of primitive type, that is their initial spicules are not differentiated into an apical and a basal group and are not connected by arches to form a heteropolar “microsphere”. They have been assigned to five families, four of which are new (Isometractiniidae, Triumbraculidae, Hollandocachoniidae, Odoghertitidae), 10 new genera (Isometractinia, Triumbraculum, Tardentactinia, Lententactinia, Hollandocachonia, Sphaerentofurca, Stylentofurca, Zuegelifurca, Spongentofurca, Odoghertites), and 19 new species. One of the new species comes from the lower Bajocian of Oregon. A new skeletal structural term, support structure, is introduced as a special type of connection between the primary spines and the macrosphere or cortical shell.  相似文献   

3.
Mireille Gaudant 《Geobios》1978,11(2):189-210
The genus PateropercaWoodward which includes two species, P. libanicaWoodward and P. robusta nov., is described in detail on the basis of acid prepared material from the Cenomanian fish bed of Hadjula (Lebanon). It is demonstrated that Pateroperca does not belong to the Order Ctenothrissiformes contrary to the generally accepted idea. Despite the possession of characters known among Acanthoterygian fishes, it is not possible to show that this genus may be related to the Order Beryciformes and the new family Pateropercidae nov. is left as Ctenosquamata incertae sedis.  相似文献   

4.
5.
Two of the oldest known silicoflagellate-bearing sediments, lower Albian at Ocean Drilling Program Site 693 in the Weddell Sea of Antarctica and Santonian in the Devon Island sequence of the Canadian Archipelago, are re-examined with a focus on silicoflagellate genera Variramus, Cornua, and Gleserocha that lack basal rings, a feature appearing during late Santonian/early Campanian time within the genus Corbisema. The extraordinary variability of Variramus aculeifera is studied, and a new genus Gleserocha is proposed for taxa with apical structures made of three struts, but without pikes. This new genus includes previously described Variramus wisei and Cornua tapiae and new species G. harrisonii, and is here proposed as a genus transitional between Variramus and Cornua. Two unusual new species of Cornua, C. deflandrei and C. witkowskiana, are also described and a revised terminology is proposed for the skeletal components of Cornua and closely related genera.  相似文献   

6.
7.
《Comptes Rendus Palevol》2014,13(4):267-276
A new specimen of early basilosaurid, now identified as Basilotritus sp., comes from the late Middle Eocene of Ukraine. It has basilosaurid-type cheek teeth with cinguli, similar to those of Zygorhiza, and roots resembling those of Georgiacetus vogtlensis and early Neoceti; an unusual feature of these teeth is the presence of accessory denticles of the second order located on the crown denticles. The postcranial anatomy shows a mixture of primitive and advanced basilosaurid traits. The phylogenetic position of the genus Basilotritus is confirmed to be near the base of Basilosauridae, between Supayacetus and Zygorhiza. The ontogeny of the specimen from Nagornoye is characterized by large body size, slow skeletal maturation and intensive pachyosteosclerosis that are interpreted as neotenic development. Rapid tooth wear with strong apical abrasion is the result of specialized diet, possibly feeding on sharks.  相似文献   

8.
Pahl Bernier 《Geobios》1979,12(6):839-861
The genus Petrascula has not been reviewed since J. Pia in 1920. At present, seven species are attributed to this genus. Different characteris have been used to define it by the authors. After abundant sampling in the Upper Kimmeridgian or the Southern Jura Mountains, the species-type has been reviewed and divided in two species, the second one named: Petrascula guembeli nov. sp.An other level of Portlandian age, in the same azea, is very rich in Petrascula piaiBachmayer, 1944. This species which has not been observed since that time is here reviewed. Associated with this species, a new one was found and described Petrascula? bugesiaca nov. sp., in spite a doubtful genus attribution.So many different species allow the review and emendation of the genus Petrascula. Then, the other species of the genus: P. globosa (Alth) P. herakiSokac & Nikler, P. illyricaSokac & Nikler, are discussed using the new definition.  相似文献   

9.
Truyolsodontos estauni n. gen., n. sp. is described based on fossil teeth from the middle and upper Cenomanian of northern Spain. The species Protoscyliorhinus magnusLandemaine, 1991 is withdrawn from the genus Protoscyliorhinus and placed in this new one. For the new genus, the new family Truyolsodontidae is proposed.  相似文献   

10.
11.
The theca and the columnals of twenty-two lateCretaceous species of the genus Bourgueticrinus (including two new species), of one species of the genus Democrinus, of four species of the genus Conocrinus (including one new species) and of one species of the genus Paleobathycrinus known from USSR are figured and shortly described. Biometric reconstructions of stems for B. aequalis, B. bellus, B. danicus, B. fischeri and C. tauricus nov. sp. are given. A new index is used to suggest the relative flexibility of stem. Decrease in dimension and flexibility of the arms in several species take place simultaneously with an increase of stem flexibility. This fact seems to be closely related to environmental changes.  相似文献   

12.
13.
The skeletal structure of the Southern Ocean daggertooth (Anotopterus vorax) has been studied for the first time. It generally corresponds to the A. pharao skeleton, as it has been previously described. The discrepancies pertain to the authors’ other various data on both the details of the structures of branchial arches, maxillae, cranium, and axial skeleton and the traits of the Anotopterus genus, which have not been described earlier. They include the availability of a considerable number of bony ribs (epineurals and epicentrals) attached to the neurocranium bones (epiotic, intercalar, and exooccipital) and some elongated and discontinuous lateral keel bones located on both sides of the central keel bone. Cladistic analysis has been performed with the finding that the A. vorax is united with the A. pharao and the Polymerichthys fossil genus into one clade, which takes an intermediate status between the representatives of the Alepisauridae and Paralepididae families. The assumption has been made about the necessity for the restitution of the family status of Anotopteridae.  相似文献   

14.
So far, the oldest terrestrial mammal associations in Italy dates to the beginning of the Oligocene, with Anthracotheriidae being the most represented taxon. Sites from northern Italy yielded remains of the genus Anthracotherium that spread from Asia to western Europe after the Grande Coupure. A finding at Grancona, which is Priabonian in age, implies that Anthracotheriidae family reached the Italian Peninsula before the Eocene–Oligocene boundary. Thus, the dispersal of this family in northern Italy is anterior than previously believed. The fossil consists of a poorly preserved right hemi-maxilla with well-preserved P4 and M3. The shape and the size of the teeth are not compatible with the genus Anthracotherium. On the contrary, the closer affinities with the Croatian species Prominatherium dalmatinum suggest a connection between the Balkan area and the Italian peninsula and a possible new way of dispersal for this family.  相似文献   

15.
The endurance running (ER) hypothesis suggests that distance running played an important role in the evolution of the genus Homo. Most researchers have focused on ER performance in modern humans, or on reconstructing ER performance in Homo erectus, however, few studies have examined ER capabilities in other members of the genus Homo. Here, we examine skeletal correlates of ER performance in modern humans in order to evaluate the energetics of running in Neandertals and early Homo sapiens. Recent research suggests that running economy (the energy cost of running at a given speed) is strongly related to the length of the Achilles tendon moment arm. Shorter moment arms allow for greater storage and release of elastic strain energy, reducing energy costs. Here, we show that a skeletal correlate of Achilles tendon moment arm length, the length of the calcaneal tuber, does not correlate with walking economy, but correlates significantly with running economy and explains a high proportion of the variance (80%) in cost between individuals. Neandertals had relatively longer calcaneal tubers than modern humans, which would have increased their energy costs of running. Calcaneal tuber lengths in early H. sapiens do not significantly differ from those of extant modern humans, suggesting Neandertal ER economy was reduced relative to contemporaneous anatomically modern humans. Endurance running is generally thought to be beneficial for gaining access to meat in hot environments, where hominins could have used pursuit hunting to run prey taxa into hyperthermia. We hypothesize that ER performance may have been reduced in Neandertals because they lived in cold climates.  相似文献   

16.
In the present paper, we describe and figure some rare lower Aptian (Lower Cretaceous) helical ammonoids from the Deshayesites deshayesi Zone of the Argiles à Plicatules Formation (Paris Basin, NE France). Those are the only helical ammonoids known in this zone so far. They were only occasionally evoked in literature and this is probably on the basis of the specimens here described that, according to us, the genus Toxoceratoides (Helicancylidae) was wrongly regarded as possessing an early helical spiral part. We demonstrate here that these specimens are not belonging to Toxoceratoides nor Helicancylidae: they are interpreted as ‘abnormally’ helical representatives of the genus Ancyloceras (Ancyloceratidae) or a new taxon of Ancyloceratidae.  相似文献   

17.
《Comptes Rendus Palevol》2019,18(4):449-454
The saber-toothed cat Smilodon is a characteristic genus of the Pleistocene faunas of the American continent. Smilodon belongs to an extinct clade of felids that had hypertrophied blade-like upper canines. Because the length of the canines is so extreme, the killing bite of Smilodon is a hotly debated topic in vertebrate paleontology. Some authors have proposed that saber-toothed cats had a weak bite and their canines were fragile, not useful for attacking prey or penetrating bones. The aim of the present contribution is to describe two new specimens of Smilodon populator that have injuries on their skulls. Although it cannot be ruled out that the injuries were caused by a potential prey kicking the skull, the size, shape and general features of the injuries suggest that they were inflicted by the upper canines of another Smilodon individual during agonistic interactions.  相似文献   

18.
The most striking feature of peafowl (Pavo) is the males'' elaborate train, which exhibits ocelli (ornamental eyespots) that are under sexual selection. Two additional genera within the Phasianidae (Polyplectron and Argusianus) exhibit ocelli, but the appearance and location of these ornamental eyespots exhibit substantial variation among these genera, raising the question of whether ocelli are homologous. Within Polyplectron, ocelli are ancestral, suggesting ocelli may have evolved even earlier, prior to the divergence among genera. However, it remains unclear whether Pavo, Polyplectron and Argusianus form a monophyletic clade in which ocelli evolved once. We estimated the phylogeny of the ocellated species using sequences from 1966 ultraconserved elements (UCEs) and three mitochondrial regions. The three ocellated genera did form a strongly supported clade, but each ocellated genus was sister to at least one genus without ocelli. Indeed, Polyplectron and Galloperdix, a genus not previously suggested to be related to any ocellated taxon, were sister genera. The close relationship between taxa with and without ocelli suggests multiple gains or losses. Independent gains, possibly reflecting a pre-existing bias for eye-like structures among females and/or the existence of a simple mutational pathway for the origin of ocelli, appears to be the most likely explanation.  相似文献   

19.
《Comptes Rendus Palevol》2016,15(8):927-940
Although the pika from the Moldovan Kalfa locality (early MN10) — representing the oldest European record of Ochotoninae (the clade derived from Bellatona) — is of crucial importance to understand the earliest history of Ochotona, its taxonomy has remained unclear until now. The paper fills the gap by providing a detailed revision of the type material from Kalfa, originally referred to Proochotona kalfense. The analysis is supported by a direct comparison with type materials of Proochotona eximia, Bellatonoides eroli, and Ochotona ozansoyi, the important early ochotonines of the peri-Paratethyan area. The genus Proochotona is regarded here as a junior subjective synonym of Ochotona. The specie kalfense is confirmed to be valid, undoubtedly belonging to the genus Ochotona. It demonstrates an occurrence of a surprisingly advanced p3 phenotype already present in the pre-Turolian of Europe. At the Holoarctic scale, a detailed synoptic survey and discussion of the fossil record, taxonomy, and phylogeny of the oldest representatives of Ochotoninae are provided.  相似文献   

20.
In this report, a molecular phylogeny based on the plastid gene matK and on the region between the genes trnL and trnF, and a chemical relationship based on the pattern of sesquiterpenes, is proposed for Aristolochia species from southeastern Brazil. We found that Aristolochia is a monophyletic genus and species considered to be derived contain labdanoic acids (LAs) in their leaves. The phenetic relationship recovered with sesquiterpenes did not agree with the phylogenetic relationships for Aristolochia, and three main clusters were recognized, namely, germacrene-D, germacrene-C and Z-caryophyllene groups. The presence of different sesquiterpene structures in species that are phylogenetically closely related may reflect adaptations to avoid predation of herbivores specialized in feeding on Aristolochiaceae plants.  相似文献   

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