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1.
New osteological material of the endemic deer from Lunel-Viel and l’Igue des Rameaux (France) reveals its evolutionary specialization, and gives reason for establishing a new genus,Haploidoceros, with a single speciesH. mediterraneus (Bonifay, 1967). The cranial proportions and morphology suggest thatH. mediterraneus is close to the Late Villafranchian speciesMetacervocerus rhenanus, which may be a possible forerunner of the deer under study. The evolutionary origin ofH. mediterraneus took place in the Iberian glacial refugia during the “Mindel glaciation” of the early Middle Pleistocene. The North-East distribution ofH. mediterraneus was limited by unfavorable climate influence of the Arctic and Alpine Ice Shields.   相似文献   

2.
Pleistocene rhinoceroses are poorly documented in Turkey where they have been reported only from the late early Pleistocene (1.3–1.1 Ma) travertine deposits of the Denizli Basin. In this work, new rhinoceros remains collected from this basin are assigned to a relatively large-sized Stephanorhinus hundsheimensis on the basis of their morphology and morphometry. The first Turkish record of this species is approximately coeval with the first appearance of Shundsheimensis in Europe, chronologically referred to the late early Pleistocene, ca. 1.2 Ma. During that time, Setruscus still survived in Iberian Peninsula, central Italy and Dacian Basin. The presence of two successive evolutionary morphs for Shundsheimensis during the Pleistocene is not confirmed.  相似文献   

3.
Fundamental uncertainties exist in the study region about the former lowland vegetation at local scales. All existing palaeoecological results are derived from sediments of medium- to large-sized sites (8–5000 ha), which are thought to record mainly regional vegetation in their pollen content. Therefore the very small mire at Balladrum (0.05 ha) was analysed for pollen, plant-macrofossils, and charcoal and the results compared with those of previous studies in the same region. Common regional signals were detected, but also new insights for the tree species Pinus cembra (L.), Abies alba (Mill.) and Castanea sativa (Mill.). Our palaeobotanical data reveal the local dominance of the timberline species P. cembra during the Lateglacial (16500–14250 cal b.p.) at low-altitudes. For A. alba an early presence in the area is suggested by pollen data, corroborating previous high-altitudinal studies indicating the presence of glacial refugia in the region. Occasional findings of C. sativa pollen throughout the Holocene may indicate the local but very rare presence of this species in the Insubrian Southern Alps, in contrast to the conventional opinion that C. sativa was introduced during the Roman Period. Altogether the results confirm the need of multiproxy palaeobotanical records from basins of variable size to assess the past composition of vegetation more accurately. Communicated by F. Bittmann  相似文献   

4.
The assignment of fossil hominoid jaws from the Plio/Pleistocene of Hadar to a single genus,Australopithecus Dart, 1925, is a misnomer. They are morphologically unrestricted to and inconsistent with the diagnosis and evolutionary trend ofAustralopithecus. The morphological pattern of four large jaws is indeed australopithecine and similar toA. africanus Dart, 1925, but six small jaws reveal a pre-habilis stage of dental development early in theHomo lineage. On the basis of their unique hominine dentition, they are reinterpreted as representing a new species,Homo antiquus n.sp.  相似文献   

5.
《Geobios》1986,19(1):17-31
The Pleistocene mammalian fauna of Sardinia isendemic and consists of only a few taxa, indicating island conditions at the time.A sharp faunal break in the Middle Pleistocene separates an older fauna with Nesogoral from a younger one (Middle/Upper Pleistocene) which contains mainly deer (Megaceros cazioti), and ochotonid (Prolagus sardus), a small canid (Cynotherium sardous), and Tyrrhenicola.Commonly paleoecological conditions on islands have led to the development of faunas with dwarfed species, showing a low gear locomotion due to lack of large carnivores. In this aspect the younger Pleistocene fauna of Sardinia is different. A deer with the proportion of mainland species and a small canid were found. This is suggestive of the presence of a large predator. Indeed, together with this fauna a human temporal bone, showing some distinctive characters, was found in Grotta di Corbeddu, Oliena, Sardinia.These findings gave rise to further excavations in the same cave. A paleolithic settlement was discovered and two types of bone artefact could be distinguished. 14C dating revealed an age of 13590±140 yrs. B.P.These results suggest the development of an endemichuman culture, adapted to the restricted island environment and to the monotonous prey of deer and ochotonids, different from any known culture of that age.  相似文献   

6.
Fossil species ofMelanopsis from a freshwater formation in the Jordan Valley (near Al-Qarn) were investigated and the deposits containing these species are formally described as Al-Qarn Formation. Four species were found:Melanopsis buccinoidea Olivier,M. tchernovi Heller & Sivan,M. costata Olivier andM. aaronsohni Blanckenhorn.Melanopsis costata was represented by two groups, “stepped” and “non-stepped”, the latter differing in its lower figurativity index. Intermediates were found betweenM. buccinoidea andM. tchernovi; they may be hybrids. TheMelanopsis assemblage bridges the faunal gap, in the Jordan Valley, between the 2 Ma lake of ‘Erq el Ahmar on the one hand and the 0.8–1.7 Ma lake of ‘Ubeidiya on the other. This suggests an early Pleistocene age of about 1.8 million years for the Al-Qarn Formation.  相似文献   

7.

Several porcupine taxa are reported from the middle Miocene to the early Holocene in the Old World. Among these, five species of the subfamily Hystricinae occurred in Africa approximately in the last 6 Ma: the extinct Hystrix makapanensis, Hystrix leakeyi, and Xenohystrix crassidens and the still living Hystrix africaeaustralis and Hystrix cristata. The large-sized H. makapanensis is reported from numerous sites in East and South Africa between the early Pliocene and Early Pleistocene. In this paper, we describe a new mandible of H. makapanensis from the world-renowned Tanzanian paleontological and archeological site of Olduvai Gorge (HWK West; lowermost Bed II; ca. 1.8–1.7 Ma). The discovery of the new mandible triggered a comprehensive review of the entire African record of H. makapanensis. In particular, we describe or re-analyze the samples from South Africa (Makapansgat Limeworks, Gondolin, Kromdraai, Swartkrans, and Sterkfontein), Tanzania (Olduvai and Laetoli), Ethiopia (Omo Shungura and Hadar), and Kenya (Chemeron), enriching the quantity of specimens confidently referable to this species and above all improving the information on its craniodental anatomy. On this basis, we: (1) propose an emended diagnosis of H. makapanensis; (2) point out the morphological and biometric differences between H. makapanensis and other African Hystricinae (also in terms of body mass); and (3) broaden the knowledge on the geographical and chronological distribution of this extinct species.

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8.
Recently,Yoshikawa andDeguchi (1992) reported an unusually high frequency (40%) of two-rooted maxillary canines inMacaca fuscata females and a complete absence of this trait in males. In the present study, canine root development and morphology was examined using cephalographs taken on 50 male and 50 femaleMacaca nemestrina, and 20 male and 20 femalePapio cynocephalus for comparison with the Japanese macaque. The results showed no double-rooted canines present in either species in the upper or lower canines. This supports the general rule that, among primates, canines possess a single-root. It was further suggested that the two-rooted canines inM. fuscata may be the result of the founder effect, i.e. that the genes for this trait may have been carried by the initial populations when they arrived on the islands sometime during the middle to late Pleistocene.  相似文献   

9.
The deer ked, Lipoptena cervi L. (Diptera: Hippoboscidae), is an ectoparasitic fly that spread to Finland in the early 1960s from the southeast across the Soviet border. It is currently a common parasite of the moose, Alces alces (Artiodactyla: Cervidae), in the southern part of the country and its area of distribution is gradually spreading to Finnish Lapland, where it will come into contact with another potential cervid host, the semi‐domesticated reindeer, Rangifer tarandus tarandus. The aim of this study was to determine the intensity of deer ked parasitism on the moose in eastern Finland. Whole skins of 23 moose were examined for the presence of deer keds, which were extracted and their total numbers estimated. The intensity of deer ked parasitism was correlated to the age, sex, skin area and anatomical region of the host. Bulls had the highest total number of keds (10616 ± 1375) and the highest deer ked density (35.7 ± 4.4 keds/dm2 of skin). Cows had a higher total number of keds than calves (3549 ± 587 vs. 1730 ± 191), but ked densities on cows and calves were roughly equal (11.8 ± 1.7 vs. 9.4 ± 1.1 keds/dm2 of skin). The density of keds was highest on the anterior back, followed by the posterior back, front limbs, abdomen, head and hind limbs. The sex ratio of deer keds was close to equal (male : female, 1.0 : 1.1). After they had consumed blood, male keds were heavier than females. As the total numbers and densities of deer keds were higher than reported previously on moose or for any other louse fly species, the effects of parasitism on the health of the host species should be determined.  相似文献   

10.
Isotricha jalaludinii n. sp. found in the rumen of lesser mouse deer, Tragulus javanicus, in Malaysia was described and illustrated. This new species is characterized by the location and direction of the vestibulum, shape of the macronucleus, and absence of a dent at the vestibular opening. The presence of single peculiar isotrichid species in the rumen of mouse deer, which is recognized as one of the most primitive ruminants, suggests that the isotrichid ciliates similar to I. jalaludinii and Isotricha intestinalis were established at a fairly early period during the evolution of ruminants.  相似文献   

11.
New material of a chalicothere was recently found from Tsaidam Basin, the only late Tertiary locality within the northern Qinghai-Tibetan Plateau established byBirger Bohlin during the Sino-Swedish Expeditions in 1927–33. A partial lower jaw with two molars helps to identify it asChalicotherium cf.C. brevirostris (Colbert), a species found in Chinese Tunggurian age (middle Miocene). Occurrence ofChalicotherium in the Tsaidam Basin indicates the presence of a wooded environment along freshwater streams, a condition much milder than the desert environment at the present time. The Tsaidam fauna thus provides a reference point in the current debate on the timing of environmental deterioration during the uplift of Tibetan Plateau.
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12.
Stephanocemas Colbert, 1939 is one of the earliest groups of deer (Cervidae) that shows indications of shedding their antlers, and as such, occupies a special position in the transition from nondeciduous to deciduous antlers in the evolution of cervids. Despite this basal position in cervid phylogeny, however, it has a highly peculiar, palmate antler morphology that is easily recognized in the fossil records of the early to middle Miocene of Eurasia. A new species, Stephanocemas palmatus sp. nov. , is described based on three partial antlers ranging from juvenile to full adult individuals, recently collected from the late middle Miocene Lower Youshashan Formation in the Qaidam Basin of northern Tibetan Plateau. Another indeterminate species (Stephanocemas sp.) of much smaller size and primitive characteristics is described from more fragmentary materials in strata lower than the level of S. palmatus but still middle Miocene in age. To the extent that it was possible, we also attempted to place into modern stratigraphical context historical collections of Stephanocemas from Qinghai Province that were obtained during the Sino‐Swedish Expeditions in the 1930s. These materials were described by Birger Bohlin in 1937 but their stratigraphical context has been in question ever since. A species‐level phylogeny suggests that S. palmatus is the most derived among known species, with its large size, great expansion of the palm part of the antler, and horizontally radiating tines. We recognize a Paradicrocerus clade that includes P. flerovi Gabuniya, 1959, P. elegantulus (Roger, 1898), and P. brevistephanos (Baschanov & Nurumov, 1955); the latter two were traditionally regarded as belonging to Stephanocemas. As a result, the Paradicrocerus clade is largely European and western Asian, whereas the restricted Stephanocemas is now Asiatic in geographical distribution. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 680–695.  相似文献   

13.
Three species of the genusPicris L. are native in Tropical Africa:P. abyssinica Sch. Bip. (Ethiopia),P. xylopoda Lack, spec. nova (Nigeria, Ethiopia) andP. humilis DC. (Senegal, Mali). There are indications that the two perennial species,P. abyssinica andP. xylopoda, are related to and have evolved from a primitive Central Asiatic stock in a manner parallel to many African species ofCrepis L.P. humilis, on the other hand, is a small annual plant with a high number of derived characters. The introduced species of European origin growing south of the Sahara are briefly mentioned.  相似文献   

14.
The Pleistocene to Holocene transition was accompanied by a worldwide extinction event affecting numerous mammalian species. Several species such as the woolly mammoth and the giant deer survived this extinction wave, only to go extinct a few thousand years later during the Holocene. Another example for such a Holocene extinction is the Don‐hare, Lepus tanaiticus, which inhabited the Russian plains during the late glacial. After being slowly replaced by the extant mountain hare (Lepus timidus), it eventually went extinct during the middle Holocene. Here, we report the phylogenetic relationship of L. tanaiticus and L. timidus based on a 339‐basepair (bp) fragment of the mitochondrial D‐loop. Phylogenetic tree‐ and network reconstructions do not support L. tanaiticus and L. timidus being different species. Rather, we suggest that the two taxa represent different morphotypes of a single species and the extinction of ‘L. tanaiticus’ represents the disappearance of a local morphotype rather than the extinction of a species.  相似文献   

15.
A study of both silicified and nonsilicified specimens of Permian reticularioid brachiopods from South China suggests thatPermophricodothyris, a genus previously rarely reported from China, is actually very common and abundant in the Middle and especially Upper Permian of South China. This study also clarifies, for the first time, that many of the reticularioid brachiopod species previously described asSquamularia in fact belong toPermophricodothyris. The new data presented in this paper also allows a critical evaluation ofPermophricodothyris in relation to its closest allies:Phricodothyris, Squamularia, Bullarina andNeophricodothyris. The revision reveals that a total of 18Permophricodothyris species are present in the Middle and Upper Permian of South China, with only one species,P. squamularioides, having survived the Permian-Triassic mass extinction. Two species,P. grandis (Chao) andP. guangxiensis Han, Zhou & Wang, are redescribed here, providing critical new information on the morphology and taxonomy of these species.  相似文献   

16.
The nomenclatural history of the generic nameParmeliopsis is reviewed. Its correct citation is found to beParmeliopsis (Nyl. exStizenb.)Nyl., dating from 1866, not 1869 as commonly cited, withP. placorodia (Ach.)Nyl. as holotype species. There is consequently no nomenclatural problem to the adoption ofForaminella Fricke Meyer, typified byF. ambigua (Wulfen)Fricke Meyer for theParmeliopsis species with falcate conidia. A synopsis of the nomenclature of the North American and European species of both these genera is included.  相似文献   

17.
A multivariate analysis has been performed in order to study the polymorphisms of the three species ofPotentilla sect.Recta (Th. Wolf)Juzepchuk represented in the Iberian Peninsula:P. asturica Rothm.,P. hirta L. andP. recta L. The variability of 20 characters (quantitative, binary and qualitative) has been evaluated in 76 collections mostly from the Iberian Peninsula and from other European territories, but also from North America, and North Africa. The analyses performed provide support for the recognition of the three species. The most discriminant among the quantitative characters is the width of the long trichomes on the stem, and then the width of the long trichomes on the leaves and the maximum length of the long trichomes. The interval of number of carpels, presence or absence of short eglandular trichomes and the abundance of long eglandular trichomes (>3 mm) are the most discriminant ones among the qualitative ones. The taxonomical position ofP. asturica, which has been previously subordinated as a subspecies within the other two taxa, is discussed. Our results support a good delimitation of this taxon which, on the basis of the morphological characters studied by us, seems to be morphologically more close toP. hirta than toP. recta, but differs significantly from both. A key to the three species is provided.  相似文献   

18.
Summary The pattern of allosteric regulation of aspartokinase activity was determined in species of Beneckea and in the marine, luminous bacteria. The results indicated that these organisms have at least three isofunctional aspartokinases of which the first is inhibited by l-threonine, the second is inhibited by l-lysine, and the third is unaffected by either l-threonine or l-lysine. The homoserine dehydrogenase activity is clearly separable from the l-lysine-sensitive aspartokinase, that may be associated with one (or both) of the other isofunctional aspartokinases.The species of Beneckea and luminous bacteria studied varied in the relative levels of the three isofunctional aspartokinases. B. parahaemolytica, B. alginolytica, B. pelagia, B. neptuna, B. harveyi, B. nigrapulchrituda, B. natriegens, and Photobacterium fischeri had predominant levels of the l-lysine-sensitive activity; B. campellii, P. phosphoreum, and P. mandapamensis had predominant levels of the l-threonine-sensitive activity; while in B. nereida these two activities were approximately equivalent. Species of Beneckea could be distinguished from P. fischeri on the basis of the sensitivity of their aspartokinase activities to inhibition by l-lysine. In P. fischeri 10.3×10-5 M l-lysine was required for a 50% inhibition of the l-lysine-sensitive enzyme, while in species of Beneckea 0.5–2.7×10-5 M l-lysine was required to achieve the same level of inhibition.Non-standard abbreviations DAHP 3-deoxy-d-arabino-heptulosonate 7-phosphate - GC guanine plus cytosine  相似文献   

19.
A reexamination of the holotype frontoparietal of Pelobates praefuscus Khosatzky, 1985 from the Pliocene of Moldova and an investigation of newly referred frontoparietal reveal previously unknown characters for this species. P. praefuscus, considered a synonym of Pelobates fuscus, is regarded here as a separate species. It differs from P. fuscus in the presence of frontoparietal-squamosal contact and medial position of the foramen arteriae occipitalis and from all extant Pelobates in having the arteria orbitonasalis open posteriorly. The last character, previously known only in early Miocene Pelobates, is shown to be present in late Miocene and early Pliocene congeners, whereas in late Pliocene–Pleistocene congeners, the posterior part of the arteria orbitonasalis generally is covered ventrally by bone.  相似文献   

20.
《Geobios》2016,49(4):265-283
The unusual cranial morphology of the endemic extinct African deer Megaceroides algericus (Lydekker, 1890) is described. Some details of cranial and dental morphology suggest that M. algericus is closely related to the Eurasian giant deer Megaloceros giganteus (Blumenbach, 1799). The paper presents also a discussion on paleoecology and functional morphology of M. algericus, as well as its origin, phylogenetic and taxonomic position. Megaloceros mugarensis (Di Stefano, 1996) from the middle Pleistocene of Levant is regarded as a probable forerunner of M. algericus.  相似文献   

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