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A new fossil species of Vallisneria (V. janecekii Bogner & Kva?ek, sp. n., Hydrocharitaceae) is reported from Early Miocene freshwater lake deposits of the North Bohemian brown coal basin (Czech Republic). It is based on a single fragmentary sterile plant bearing two clusters of ribbon-shaped widely serrulate leaves on a short rhizome. It is a potential producer of seeds described from equivalent and slightly older deposits in Saxony (Germany) as Vallisneria ovalis Mai.  相似文献   

3.
山东临朐中新世山旺组昆虫蛀蚀遗迹   总被引:3,自引:0,他引:3  
郭双兴 《古生物学报》1991,30(6):739-742
本文研究的昆虫遗迹化石材料产自山东临朐中新统山旺组,是鞘翅目棘胫小蠹虫科单配类群的雌虫在成熟后钻入榆树皮内产卵及孵化的幼虫成长时食木质部而留下的幼虫室雕痕。此遗迹化石的发现证明在中新世时中国华北地区已有小蠧虫生存,为丰富的山旺昆虫化石又增加新记录。  相似文献   

4.
A fossil specimen identified as a silurid catfish (92.5 mm SL) was collected from the Middle Miocene Sanuki Group (15.8±0.9 Ma) of Ohkawa, Kagawa Prefecture, Japan. This is the oldest certain record of a silurid catfish. Morphological characteristics of the specimen are as follows: 52 or 53 vertebrae, 61 or 62 anal fin rays, a stout, short spine (11%SL) and 10 or more soft rays of the pectoral fin, 8 or more pelvic fin rays, 8 or more branchiostegal rays, head length of ca. 24%SL, and most probably not forked caudal fin. The fossil specimen is clearly distinct from three extant silurids in Japan, and probably belongs to an undescribed form considering its geological age.  相似文献   

5.
Maiakarichnus currani ichnogen. et isp. nov. is a crustacean trace fossil from the Upper Miocene Camacho Formation of Uruguay. This trace fossil is a subspherical chamber preserved in full relief, with numerous thin shafts radiating in a stratigraphically upward direction mainly from its upper part and from the sides. In the Camacho Formation it can be found intergrading with Ophiomorpha and Thalassinoides . Previous (unnamed) findings of similar material are only from the Pamlico Morphostratigraphic Unit (Pleistocene) of North Carolina; these have been interpreted as callianassid brood structures. In this paper we also interpret Maiakarichnus as a brood structure of callianassid origin based on its association with Thalassinoides and Ophiomorpha .  相似文献   

6.
The Kutch region of western India (Gujarat State) is today arid to semiarid and characterised by mostly ephemeral streams which carry water during the monsoon. The uneven distribution of rainfall and disturbed topography are the result of climate change during the Cenozoic period. Two fossil woods, namely Bauhinium palaeomalabaricum Prakash and Prasad (Fabaceae) and Ebenoxylon indicum Ghosh and Kazmi (Ebenaceae), are described from Kutch in order to provide insights into the palaeovegetation and palaeoclimate. Because the modern representatives of the present and previously described taxa from the same horizon are thermophilic in nature and grow in evergreen to deciduous forests, a warm and humid climate is interpreted. Furthermore, the finding of some mangrove taxa in the assemblage indicates the lagoonal to intertidal environment at the time of deposition.  相似文献   

7.
The crushed skull ofOreopithecus bambolii (IGF 11778) has been fully reconstructed in Florence, Italy and shows important differences with previous drawn reconstructions. The jaws are massive and projecting, such that the face is not as short as was believed. The incisors are small and do not project significantly forward beyond the position of the canines, and the anterior symphyseal surface of the mandible projects in front of the canines and well infront of the upper canines and incisors. There is a prominent sagittal crest, a high ascending mandibular ramus, and a nuchal plane which faces postero-inferiorly.  相似文献   

8.
The microsoroid ferns make up a large group in the family Polypodiaceae, easily characterized by the combination of at least partly clathrate rhizome scales and anastomosing reticulate venation. The diversification of this clade is poorly known, both because of unresolved generic delimitations and the lack of fossil records. In this work, we describe the first microsoroid macrofossil: Palaeosorum ellipticum sp. nov. F. M. B. Jacques & Z. K. Zhou. The fossil specimen, represented by part and counterpart, was found in the middle Miocene sediment of the Dajie Formation in Ailsohan, central Yunnan, southwest China. Epiphytic ferns belonging to Drynariaare found in different locations in Yunnan during the Pliocene. The fossil described in this study deepens the occurrence of epiphytic ferns in Yunnan back to the middle Miocene. It demonstrates that forests with complex ecological relationships have existed in southwest China for more than 10 million years.  相似文献   

9.
Six new fossils of Micromalthus (Coleoptera: Archostemata) from Dominican amber are compared with extant and previously described fossil micromalthid beetles. The amber inclusions are well preserved and all important morphological features are visible. Taking into account the morphological variability of the extant species Micromalthus debilis LeConte, 1878 , it is not possible to find any morphological features that distinguish the fossils from the extant species. This also applies to the Dominican amber inclusion described as Micromalthus anasi Perkovsky, 2008, which therefore is considered a junior synonym of M. debilis. The lack of morphological change in M. debilis over time might possibly be explained by unusually stable environmental conditions, as this species occupies a very specialized ecological niche in decaying timber. A general survey of fossil insects indistinguishable from extant species is presented. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 300–311.  相似文献   

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11.
Two Hipparion species, H. forstenae and H. hippidiodus from Gaojiashan locality in the Linxia Basin, Gansu, China are described in this paper, with the first presence of the former in the Linxia Basin. The lower cheek teeth of Hipparion from Gaojiashan bear deep ectoflexids, and after comparisons to other Chinese Hipparion fossils with deep ectoflexids, the mandibles with deep ectoflexids on the lower premolars suggest their attributions to H. forstenae. The presence of a deep ectoflexid on p2 may be interpretable as an intraspecifically variable feature in H. forstenae, and can also be found in H. dermatorhinum. Besides the Hipparion material, at least 8 species of large mammals occur at the Gaojiashan locality, including Adcrocuta eximia, Chilotherium wimani, Shansirhinus ringstroemi, Eucladoceros cf. proboulei, Palaeotragus cf. coelophrys, Giraffidae gen. et sp. indet., and the previously studied Promephitis hootoni and Eostyloceros hezhengensis. Although the sample from Gaojiashan shares five species with the Yangjiashan fauna, the Gaojiashan fossil assemblage may date to the Baodean because of the presence of H. forstenae. The overall taxonomic composition of the Gaojiashan assemblage at least suggests an approximate Baodean age, which would imply survival of C. wimani into the Baodean of the Linxia Basin.  相似文献   

12.
Abstract:  Semlikiichthys is a fossil genus of perciform fish from the Neogene continental deposits of Africa. Until now, it was known in Mio-Pliocene sites of the Great Lake Region and of the River Nile by a single species, S. rhachirhinchus . Here, we describe new Semlikiichthys material recovered from Central Africa (Upper Miocene of Toros-Menalla, western Djurab, Chad), and compare it to S. rhachirhinchus , which is the only known species of the genus, and also with Lates niloticus , which is the fish in African Neogene deposits that most closely resembles it. We attribute the Chadian material to Semlikiichthys darsao sp. nov., based on ten osteological characters of the neurocranium, the maxilla, the dentary and the first vertebra. Our comparative anatomical study also enables us to provide a revised diagnosis for the genus and to reconsider the taxonomic attribution of the fossils assigned to it. Furthermore, the fossil record of Semlikiichthys supports a connection between sub-basins of the Nilo-Sudanese region during the Miocene, and a disruption between the Great Lake and the Nile Basin on the one hand and the Chadian Basin on the other before 7 Ma.  相似文献   

13.
A number of cupressaceous fossil leaves are described in this paper that come from the lower Miocene of Inner Mongolia, northern China. These new examples of fossil leaves are compressed, have their branchlets arranged in a plane, either spreading or ascending, and are flat. These specimens also possess scale-like leaves that are dimorphic, preserved facial leaves that are rhomboidal and have obtuse apices, and lateral leaves that are boat-shaped and have slightly incurved apices. The epidermal cells of these fossils are quadrangular, rectangular, or narrowly rectangular, while the leaves are amphistomatic, and stomata are elliptical or oblong, and monocyclic. In comparison with both living and related fossil taxa, we identify the new fossils as Platycladus preorientalis sp. nov. Taken in combination with a molecular phylogenetic analysis, the new fossils suggest that the genus Platycladus originated in the Oligocene in mid and high Asian latitudes. Thus, the ancient Platycladus lineage probably migrated from Europe to Asia following the closure of the Turgai strait during the Oligocene.  相似文献   

14.
The relationship between femoral neck superior and inferior cortical thickness in primates is related to locomotor behavior. This relationship has been employed to infer bipedalism in fossil hominins, although bipeds share the same pattern of generalized quadrupeds, where the superior cortex is thinner than the inferior one. In contrast, knuckle‐walkers and specialized suspensory taxa display a more homogeneous distribution of cortical bone. These different patterns, probably related to the range of movement at the hip joint and concomitant differences in the load stresses at the femoral neck, are very promising for making locomotor inferences in extinct primates. To evaluate the utility of this feature in the fossil record, we relied on computed tomography applied to the femur of the Late Miocene hominoid Hispanopithecus laietanus as a test‐case study. Both an orthograde body plan and orang‐like suspensory adaptations had been previously documented for this taxon on different anatomical grounds, leading to the hypothesis that this fossil ape should display a modern ape‐like distribution of femoral neck cortical thickness. This is confirmed by the results of this study, leading to the conclusion that Hispanopithecus represents the oldest evidence of a homogeneous cortical bone distribution in the hominoid fossil record. Our results therefore strengthen the utility of femoral neck cortical thickness for making paleobiological inferences on the locomotor repertoire of fossil primates. This feature would be particularly useful for assessing the degree of orthograde arboreal locomotor behaviors vs. terrestrial bipedalism in putative early hominins. Am J PhyAnthropol 2012. © Wiley Periodicals, Inc.  相似文献   

15.
广西宁明盆地第三纪鱼类化石生物地层   总被引:3,自引:0,他引:3  
1宁明盆地的研究历史概况 宁明盆地位于广西西南部,十万大山西北坡,在中国第三系地层区划上属岭南地层区右江地层分区(李云通等,1984)。这是一个由NWW向张扭性断裂和NEE向压扭性断裂控制所形成的近东西向长菱形盆地(李嵘等,1995),其上发育着一套称为邕宁群的第三纪沉积,厚度较大,以砂岩、泥岩夹砂岩为主,角度不整合于侏罗系之上,含有鱼类、植物和孢粉等化石。  相似文献   

16.
《Palaeoworld》2021,30(4):746-756
A new fossil species, Cedrus anatolica n. sp., is described from the early Miocene Hançili Formation of Turkey. All analyses were performed on the thin sections housed at Istanbul University – Cerrahpasa. The new species was interpreted as having the closest affinity with the modern Mediterranean species Cedrus atlantica (Endlicher) Manetti ex Carriere and Cedrus libani Richard. The evolutionary line shows some changes in wood anatomy. From the early Cretaceous to the early Miocene, the pits on the tangential walls of the tracheids gradually decreased, the height of rays increased and the number of epithelial cells in the traumatic resin canals increased slightly. These features are similar in three modern species; other wood anatomical features are also quite stable among the new fossil and modern species.  相似文献   

17.
Abstract

A contribution to the fossil Silicoflagellates of the late Miocene in Central Italy. - A microscopic analysis of fourteen diatomite samples from a Messinian (late Miocene) stratigraphic series, in central-eastern Italy, has been carried out in order to verify the presence of Silicoflagellates. The skeletons of eight taxa were found in good condition and identified. The most abundant and continuous in the stratigraphic series examined are Dictyocha fibula and Distephanus speculum, also known in the present-day seas; Cannopilus sphaericus, a very rare and interesting species extinct in the Miocene, is limited to only two samples. On the basis of the Silicoflagellates found, it is possible to suggest that they lived in an open sea with 30–40‰ salinity and a temperature of 10–20°C. A very similar situation is present nowadays in the middle-western Adriatic Sea.  相似文献   

18.
禄丰古猿化石地点地层概述   总被引:5,自引:0,他引:5       下载免费PDF全文
本文较详尽地记述了云南禄丰古猿化石地点附近的地质、地貌、地层情况以及产出古猿及大量脊椎动物化石的剖面。  相似文献   

19.
The genus Elaeocarpus contains approximately 360 species and occurs in mesic forest communities from India, through to China, Southeast Asia, New Guinea, Australia, and New Caledonia. Elaeocarpus fossils are best known from the Eocene to the Miocene of Australia and the late Pliocene–early Pleistocene of India, but have not been documented from East Asia before. Here we describe six new species of Elaeocarpus, E. nanningensis sp. nov. from the late Oligocene Yongning Formation of the Nanning Basin, E. presikkimensis sp. nov. from the Miocene Erzitang Formation of the Guiping Basin, E. prerugosus sp. nov., E. prelacunosus sp. nov., E. preserratus sp. nov., and E. preprunifolioides sp. nov. from the late Miocene Foluo Formation of the Nankang Basin in Guangxi, South China. This is the first reliable report for the genus occurring in East Asia, and the fossils indicate that Elaeocarpus had colonized this region by the late Oligocene and represented by a morphologically diverse group of species by the late Miocene. This sheds new insights into the timing and migration patterns of the genus in East Asia. Elaeocarpus is typically a rainforest genus occurring in mesic forests. Based on the habitat of their morphologically similar modern relatives we propose that these three sedimentary basins were warm and wet adjacent to mountainous regions with the evergreen or rain forests during the late Oligocene to Miocene.  相似文献   

20.
The taxonomic affinities of the Eppelsheim femur, known as Paidopithex, have been unclear for more than a century. Over the years, due to similarities with Pliopithecus, some authors have considered it a large pliopithecid, while others refer to it as Dryopithecus. The issue could not be resolved, because no definitive Dryopithecus femora were available. With the discovery of the Dryopithecus laietanus skeleton from Can Llobateres (CLl 18800), it has become possible to test the attribution of the Eppelsheim femur to Dryopithecus on the basis of direct morphological and metrical comparisons. By means of allometric techniques, we show that the Eppelsheim and D. laietanus femora fit different hindlimb morphologies with regard to relative length and relative head/neck size, with Paidopithex significantly differing from Dryopithecus, but more closely resembling Pliopithecus. Paidopithex also differs from Dryopithecus in other important aspects, such as its lower neck/shaft angle, lack of elevation of the femoral head above the greater trochanter, more posteriorly oriented lesser trochanter, and proximal shaft diameter thicker anteroposteriorly than mediolaterally. In these features, Paidopithex most closely resembles Pliopithecus in spite of differences in body mass (ca. 22 kg vs. ca. 10 kg, respectively). These features suggest that Paidopithex used a primitive locomotor pattern associated with arboreal quadrupedalism, instead of the more derived pattern displayed by Dryopithecus. Currently available evidence confirms that the attribution of Paidopithex to Dryopithecus can be rejected. Paidopithex could be a large and otherwise unknown pliopithecid, but the possibility cannot be ruled out that it represents a third kind of catarrhine.  相似文献   

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