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1.
Tracks and trackways of the ruminant goat, Myotragus balearicus Bate, 1909 are abundant in the Late Pleistocene aeolianites of the south coast of Mallorca, Spain. The carbonate aeolianites form impressive dunes and related sand ramps that were initiated as echo dunes in front of a 20–40 m high paleocliff of Miocene reefal limestone. Where the dunes built up to the cliff top, they covered it as an aeolian ramp. The dunes and sand ramps were active during the dry summer months but were passive during the wet winter period. The small, goat-like animals were abundant on the island, and for unknown reasons crossed the aeolian accumulations in large numbers. This study deals with the tracks formed in the dune deposits. All preserved trackways indicate impression into moist sand. Special features of the tracks include the structure produced by the withdrawal of the foot, here called the ‘axis’, and a disturbance zone of plastic deformation around this. On dune crests, the disturbance zone surrounds the axis more or less symmetrically. However, in addition, a ‘pressure pad’ of dislocated, slightly rotated sediment bound by curved microfaults is commonly produced posterior to the axis by propulsive pressure of the foot. On steep stoss and lee slopes, the pressure pad becomes oriented in a down-slope position as a result of gravitational slip of the walking animal. Combination of disturbance of the sediment in this way by manus followed by overprinting of similar disturbance by pes produces highly complicated track structure. This structure may be characteristic of artiodactylous mammals in soft sand, particularly aeolian deposits. The structure is designated as Bifidipes aeolis isp. nov. 相似文献
2.
A new cottid species, Porocottus leptosomus, is described on the basis of 12 specimens collected from Taean, west coast of Korea, Yellow Sea. The species is distinguished
from other species of Porocottus by the following combination of characters: a strongly compressed body, two pairs of branched cirri on the dorsal surface
of the head, bases of head cirri smooth, a single cirrus on the dorsal tip of each spine of the first dorsal fin, a single
opening of the sixth canaliculus of the infraorbital sensory canal, a long posterior medial canaliculus of the occipital canal
with the terminal pore and a few supplementary pores, and melanophores on the isthmus hidden beneath the branchiostegal membrane.
Received: January 11, 2001 / Revised: February 7, 2002 / Accepted: March 4, 2002 相似文献
3.
Background and AimsEricales are a major group of extant asterid angiosperms that are well represented in the Late Cretaceous fossil record, mainly by flowers, fruits and seeds. Exceptionally well preserved fossil flowers, here described as Glandulocalyx upatoiensis gen. & sp. nov., from the Santonian of Georgia, USA, yield new detailed evidence of floral structure in one of these early members of Ericales and provide a secure basis for comparison with extant taxa. MethodsThe floral structure of several fossil specimens was studied by scanning electron microscopy (SEM), light microscopy of microtome thin sections and synchrotron-radiation X-ray tomographic microscopy (SRXTM). For direct comparisons with flowers of extant Ericales, selected floral features of Actinidiaceae and Clethraceae were studied with SEM. Key ResultsFlowers of G. upatoiensis have five sepals with quincuncial aestivation, five free petals with quincuncial aestivation, 20–28 stamens arranged in a single series, extrorse anther orientation in the bud, ventral anther attachment and a tricarpellate, syncarpous ovary with three free styles and numerous small ovules on axile, protruding-diffuse and pendant placentae. The calyx is characterized by a conspicuous indumentum of large, densely arranged, multicellular and possibly glandular trichomes. ConclusionsComparison with extant taxa provides clear evidence for a relationship with core Ericales comprised of the extant families Actinidiaceae, Roridulaceae, Sarraceniaceae, Clethraceae, Cyrillaceae and Ericaceae. Within this group, the most marked similarities are with extant Actinidiaceae and, to a lesser degree, with Clethraceae. More detailed analyses of the relationships of Glandulocalyx and other Ericales from the Late Cretaceous will require an improved understanding of the morphological features that diagnose particular extant groups defined on the basis of molecular data. 相似文献
4.
The youngest fossil Golunda (Rodentia, Muridae) is described from the Late Pleistocene fluvio-lacustrine deposits, exposed at Dulam (Bageshwar), Kumaun Lesser Himalaya, India. The age of fossiliferrous horizon is estimated as 31,000 yr BP. A new species, Golunda dulamensis nov. sp. has highly derived characters, e.g., antero-posteriorly stretched molars, upper molars with more length and less width, stephanodonty, cusps in M 3 strongly inclined backward giving the molars a very stretched aspect, and metaconid and entoconid in M 3 forming almost straight lingual row of the cusps. G. dulamensis nov. sp. is most similar to present day G. ellioti but differs from the later slightly by larger size, a thin connection between t 4 and t 5 in M 1, and comparatively larger entoconid and very weakly developed antero-labial cusp in M 3. We suggest that highly specialized molars of G. dulamensis nov. sp. and present day G. ellioti are derivable through G. kelleri. We also propose that Golunda migrated from Asia to Africa, not from Africa to Asia as was thought by earlier workers. 相似文献
5.
Impatiens comprises more than 1000 species and is one of the largest genera of flowering plants. The genus has a subcosmopolitan distribution, yet most of its evolutionary history is unknown. Diversification analyses, divergence time estimates and historical biogeography, illustrated that the extant species of Impatiens originated in Southwest China and started to diversify in the Early Miocene. Until the Early Pliocene, the net diversification rate within the genus was fairly slow. Since that time, however, approximately 80% of all Impatiens lineages have originated. This period of rapid diversification coincides with the global cooling of the Earth’s climate and subsequent glacial oscillations. Without this accelerated diversification rate, Impatiens would only have contained 1/5th of its current number of species, thereby indicating the rapid radiation of the genus. 相似文献
6.
This article reports a new record of the greater noctule Nyctalus lasiopterus (Schreber, 1780) in the Late Pleistocene of Europe. A fragment of a left mandible from this species was collected in Layer O (around 55 ka) from the Abric Romaní rock shelter, providing evidence of the presence of the greater noctule in north-eastern Spain during the latest Late Pleistocene. The relevance of this new record, which is geographically not reported up to now in the area, is discussed in terms of environmental changes. 相似文献
7.
We present the study of rodents and insectivores from the 1995 season of excavation at the early Late Pleistocene site of Bois Roche (Charente, France). The site is a small cave with a low ceiling, used as a den by hyenas. It contains a large herbivore assemblage (mainly bovids and equids) with a smaller representation of medium-size taxa (cervids), many microvertebrates, abundant coprolites and deciduous hyena teeth, and a few lithic artifacts (Middle Paleolithic) introduced into the cave by gravity and slope wash. The rodent fauna consists of Eliomys quercinus cf. quercinus, Apodemus sp., Microtus gregalis, Microtus oeconomus, Arvicola terrestris and Dicrostonyx torquatus. Insectivores are represented by Neomys cf. fodiens. The most common species is M. gregalis which forms 93.7% of the total MNI. The micromammal fauna suggests an open landscape, with some vegetation mainly of the steppe or tundra type, with areas of water and more wet vegetation and some areas with trees. The micromammal association of Bois Roche is characteristic of a cold or very cold dry climate. 相似文献
8.
New taxonomic study of the “old collection” of Carnivora from Petralona Cave, associated to the well-known hominid skull, housed in the Geology School of the Thessaloniki Aristotle University since 1960, revealed 11 species ( Canis arnensis, Lycaon lycaonoides, Vulpes praeglacialis, Ursus deningeri, U. spelaeus, U. arctos, Pliocrocuta perrieri, Pachycrocuta brevirostris, Crocuta crocuta, Panthera leo spelaea, and Felis silvestris), which are described in detail. The species composition is typical of the eastern part of the European Mediterranean and may be divided into three biostratigraphic assemblages: early Middle Pleistocene, late Middle Pleistocene and Late Pleistocene. 相似文献
9.
A new cottid, Icelinus pietschi sp. nov., and a rare species, Sigmistes smithi Schultz, were collected from intertidal zones in the southern Kuril Archipelago. Icelinus pietschi, represented by five specimens (34.8–42.2 mm SL) from Iturup Island, is distinguished from other species of Icelinus by having the dorsal scale rows terminating before the posteriormost base of the second dorsal fin, spines absent on the dorsal surface of the head, a single common opening of the terminal pores of the mandibular canal, a cirrus on the base of the nasal spine, and a slightly bifid uppermost preopercular spine without denticles dorsally. Six examples (36.8–42.9 mm SL) from Urup Island of Sigmistes smithi, previously known only rarely from the middle of the Aleutian Archipelago, constitute the first record of the species from the western North Pacific. Received: September 26, 1999 / Revised: May 25, 2000 / Accepted: August 29, 2000 相似文献
10.
Removal of phosphorus (P) by Ceratophyllum demersum L. and associated epiphytic periphyton was quantified by measuring the disappearance of soluble reactive P (SRP) from microcosms during 1-h in situ incubations conducted over a 1-year period. Initial P concentrations in these incubations ranged from 30 to >10,000 μg P L −1. Phosphorus removal was proportional to initial P concentrations and was weakly correlated with solar irradiance and water temperature. Removal rates (0.6–32.8 mg P m −2 d −1) and kv coefficients (0.68–1.93 h −1) from experiments run at low initial P concentrations (up to 200 μg P L −1) were comparable to results reported for other macrophytes. Removal rates from experiments run at the highest (>10,000 μg P L −1) initial P concentrations (5300 and 11,100 mg P m −2 d −1) most likely represented luxury nutrient consumption and were not thought to be sustainable long term. We were unable to determine a Vmax for P removal, suggesting that the nutrient-storage capability of the C. demersum/periphyton complex was not saturated during our short-term incubations. Based on N:P molar ratios, the marsh was P limited, while the C. demersum/periphyton complex was either N limited or in balance for N and P throughout this study. However, despite its tissue stoichiometry, the C. demersum/periphyton complex always exhibited an affinity for P. It appeared that the biochemical mechanisms, which mediate P removal, at least on a short-term basis, were more influenced by increases in ambient P levels than by tissue nutrient stoichiometry. 相似文献
12.
The type specimen of Toyotamaphimeia machikanensis (Diapsida, Crocodylia) from the Osaka Group (Plio-Pleistocene) of Osaka Prefecture, Central Japan, shows multiple abnormalities. The anterior third of the mandible was amputated and shows signs of healing. The right tibia and fibula were fractured, and each of them was later fused in dislocated position with callus formation. Additionally, there are two puncture marks on a dermal scute. Based on the morphologies of these pathologies, the fauna of the community in which this animal lived, and the behavior of extant crocodilians, it is suggested that this individual survived its injuries sustained during multiple intraspecific fights for territoriality or mating. 相似文献
13.
Non-occlusal, buccal tooth microwear variability has been studied in 68 fossil humans from Europe and the Near East. The microwear patterns observed suggest that a major shift in human dietary habits and food processing techniques might have taken place in the transition from the Middle to the Late Pleistocene populations. Differences in microwear density, average length, and orientation of striations indicate that Middle Pleistocene humans had more abrasive dietary habits than Late Pleistocene populations. Both dietary and cultural factors might be responsible for the differences observed. In addition, the Middle Paleolithic Neanderthal specimens studied show a highly heterogeneous pattern of microwear when compared to the other samples considered, which is inconsistent with a hypothesis of all Neanderthals having a strictly carnivorous diet. The high density of striations observed in the buccal surfaces of several Neanderthal teeth might be indicative of the inclusion of plant foods in their diet. The buccal microwear variability observed in the Neanderthals is compatible with an overall exploitation of both plant and meat foods on the basis of food availability. A preliminary analysis of the relationship between buccal microwear density and climatic conditions prevailing in Europe during the Late Pleistocene has been attempted. Cold climatic conditions, as indicated by oxygen isotope stage data, seem to be responsible for higher densities of microwear features, whereas warmer periods could correspond to a reduced pattern of scratch density. Such a relationship would be indicative of less abrasive dietary habits, perhaps more meat dependent, during warmer periods. 相似文献
14.
The cottid genus Radulinopsis Soldatov and Lindberg is recognized as a valid taxon including two species, R. derjavini Soldatov and Lindberg and R. taranetzi sp. nov., both distributed in shallow waters around Hokkaido, Japan, and the Russian Far East. Radulinopsis taranetzi differs from R. derjavini in having an almost naked body, teeth on the prevomer, and higher meristic counts. Radulinopsis derjugini Soldatov is synonymized with R. derjavini. A key to species of Radulinopsis and related genera is given. Based on a cladistic analysis of 18 morphological characters, Radulinopsis is the sister group of the Japanese genus Astrocottus, and the monophyletic eastern North Pacific group comprising Radulinus plus Asemichthys is the sister group of the western North Pacific group of Radulinopsis plus Astrocottus. Triglops, having a wide distribution throughout the North Pacific and North Atlantic, is putatively the sister group of a monophyletic
group including these four genera. Bolin's genus Radulinus (including Radulinopsis as a subgenus) and Taranetz's subfamily Radulinae (including only Radulinus and Radulinopsis) are polyphyletic and therefore invalid.
Received: September 7, 1999 / Revised: April 28, 2000 / Accepted: August 29, 2000 相似文献
15.
This paper describes recent material gathered during the second fieldwork at Ma U'Oi in November 2002 by a Vietnamese–French–Japanese team. The Ma U'Oi cave, located in the province of Hoà Binh (60 km SW from Hanoi), northern Vietnam, belongs to a karstic network developed in Triassic dark-grey limestones. The cave is filled with coarse-grained breccias containing numerous fossil remains, partially preserved at several loci inside the cave (wall, vault and ground). We describe new teeth which confirm the occurrence of mammal taxa already mentioned at Ma U'Oi (Bacon et al., 2004)[Bacon, A-M., Demeter, F., Schuster, M., Long, V.T., Thuy, N.K., Antoine, P-O., Sen, S., Nga, H.H., Huong, N.T.M., 2004. The Pleistocene Ma U'Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments. Geobios 37, 305–314], while others, mainly microvertebrates, emphasize the occurrence of new species for the Pleistocene of Vietnam. We report here, for the first time, the occurrence of these microvertebrates of different groups (primates, rodents, insectivores, small reptiles and amphibians) in the faunal assemblage. Among mammal taxa, the presence of one more hominid affiliated to archaic Homo is also attested by our findings. U/Th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate, with fossiliferous fillings ranging from late Middle Pleistocene to Late Pleistocene. 相似文献
16.
At Cedro Peak (Manzanita Mountains, central New Mexico), the Pennsylvanian succession is divided into four formations: Sandia, Gray Mesa, Atrasado, and lower part of Bursum. The sampled limestones of the Gray Mesa and Atravasado formations yielded three age distinctive fossil assemblages: (a) latest Atokan/early Desmoinesian; (b) late early Desmoinesian, and (c) middle Virgilian. The calcareous algae, incertae sedis algae and cyanobacterial-foraminiferal consortia are described here. The following new taxa are named: Epimastoporaceae n. fam.; Anthracoporellopsis novamexicana n. sp.; Tubiphytidae n. fam.; and Latitubiphytes n. gen. 相似文献
18.
A 5.4 m peat core from the Sandy Run Creek (SRC) valley in the upper Coastal Plain of Georgia shows that before 30 ka the valley had an aggradational sandy floor with shallow swales and low ridges of 1–2 m amplitude suggesting a braided stream pattern and a low water table. The climate from 30–25 ka was cool and dry and the vegetation open grassland with stands of pine and spruce that produced few fires. At ca. 16 ka a warmer, wetter climate caused SRC to meander and incise the valley fill removing some previously deposited sediment at the site of our peat core so that sediments of 13 ka rest directly on sediments deposited at 25 ka. After ca. 13 ka higher groundwater levels initiated vertical accretion of floodplains allowing peat accumulation in shallow depressions across the valley. Pollen from the Younger Dryas period (ca. 13–11 ka) indicates a cool, moist environment of open oak woodland, mesic trees, riparian populations of alder, and reduced levels of pine . By the early to mid Holocene, tupelo and oak dominated over pine indicating wetter conditions, while sand stringers in peat record periodic heavy rains, an elevated water table, and intervals of substantial runoff. Cooling after ca. 4.5 ka brought drier and more variable conditions. Fires increased and southern pine replaced tupelo and oak. The absence of sand stringers in peat younger than 4.5 ka indicates fewer intense rainfall events. 相似文献
19.
Knowledge of the Early-Middle Pleistocene (Ensenadan Age/Stage ; ca. 1.8-0.4 Ma) South American Glyptodontidae (Cingulata) is still poor compared with the Late Pleistocene-Early Holocene taxa (Lujanian Age/Stage). This is especially true for the Glyptodontidae Panochthini, in which it is possible to recognize two Ensenadan species from the Pampean region of Argentina, Panochthus intermedius and P. subintermedius, known only by their type material. Prior to this contribution, the knowledge of P. intermedius, a taxon with biostratigraphic importance for being considered as a guide taxon of the Ensenadan Age/Stage of South America, was limited to a dorsal carapace. The finding of an exceptional almost complete specimen from the Early-Middle Pleistocene of Bolivia has allowed us to greatly improve the morphological characterization of this species, and discuss some taxonomic aspects related to the other Ensenadan Panochthini. This specimen represents the most completely known Panochthini and one of the most complete Glyptodontidae from the Early-Middle Pleistocene of South America. 相似文献
20.
In November 2002, during the second season of work by a Vietnamese-French-Japanese team, we discovered a human molar and a fragment of an occipital bone in the late Middle to Late Pleistocene cave of Ma U'Oi (Bacon et al., Geobios. 37 (2004) 305). The layer from which this material comes is the same as that in which a human lower molar was found in 2001. Both molars can be attributed to archaic Homo, and both exhibit archaic and modern traits. 相似文献
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