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1.
The genus Ventilago Gaertn. usually occurs in hot, dry, and low-altitude tropical environments. The fossil record of this genus is meager, so its origin and geographic history are still poorly understood. We describe a fossil winged fruit species-Ventilago lincangensis K. N. Liu & S. P. Xie sp. nov. from the upper Miocene Bangmai Formation of Lincang city, Yunnan Province, China. The fossil conforms to the modern genus Ventilago in architecture of the prominent fruit wing including a prominent midvein, a set of minor longitudinally secondary veins extending the full length of the fruit and reticulate higher order venation. The elliptical fruit body at the base of the wing shows an equatorial rim and has a short pedicel. This is the first report of Ventilago fruits in China, and is significant for the investigation of the origin and evolutionary history of this genus.  相似文献   

2.
丰富的化石记录显示中生代和新生代紫萁属在北半球广泛分布.本文描述了发现于福建中中新世佛昙群的紫萁属一新种:漳浦紫萁(Osmunda zhangpuensis Z.X.Wang and B.N.Sun,sp.nov.).化石小羽片保存完好,呈线状披针形,边缘具齿,羽状脉序.在该属现生种中,当前化石种与现生种Osmunda...  相似文献   

3.
A well-preserved Macaranga leaf fossil from the middle Miocene Fotan Group of Zhangpu County, Fujian, South-eastern China is examined and described as a new species, Macaranga zhangpuensis Z.X. Wang et B.N. Sun sp. nov. The present fossil species represents the highest latitudinal distribution of a reliable Macaranga fossil in the world, and we present the first Macaranga fossil described with detailed cuticular characteristics from China. Based on the global palaeogeographic distribution of Macaranga, we infer that the genus probably originated during the Oligocene in Africa and spread from Africa to India and then to South Fujian, China, further into the Mariana Islands and finally into the Philippine Islands and Malaysia, leading to its present distribution. In addition, the new leaf material described herein is the first Macaranga fossil record with three leaf tips globally. This finding demonstrates that Macaranga with three leaf tips already existed during the Miocene in Fujian, South China, and it provides new information for understanding climatic changes between the Miocene and the present -day.  相似文献   

4.
Dipterocarpus zhengae sp. nov. is described from the middle Miocene Fotan Group of Zhangpu county, Fujian Province, Southeast China on the basis of a fruit wing. Three kinds of venation of the calyx longer lobes (enlarged sepals) occur in the winged fruits of extant Dipterocarpus. The fossil species is referred to the kind having three primary veins and within that category is most similar to extant Dipterocarpus gracilis Blume in the size of the longer lobe as well as its venation. The occurrence of the fruit wing of Dipterocarpus, together with palynological evidence, indicates unequivocally that a tropical climate and tropical rain forest occurred in Zhangpu during the middle Miocene, warmer and more humid than at the present day. The palaeobiogeography of Dipterocarpus is reviewed.  相似文献   

5.
The fossil record of Lauraceae can be traced back to the Early Cretaceous of eastern Asia based on fossil flowers. Here, we refer a number of new occurrences of leaf and fruit fossils of Lauraceae from the Middle Miocene of Zhangpu, Fujian, China, to seven species. These data provide evidence supporting the fact that a diverse subtropical, or tropical, Lauraceae-dominated evergreen forest surrounded this region 15 million years ago (Mya). The Lauraceae fossils presented in this paper provide evidence for the evolution of this group as well as new materials that enable the study of the Fujian Province Neogene flora. The fossils described in this paper fill in the gaps in studies about Lauraceae pollen in the Middle Miocene from Fotan, Fujian, China. In addition, these fossils also enrich the Middle Miocene fossil records of Lauraceae in eastern Asia, especially improving the study of the macrostructures and reproductive organs of fossil Lauraceae from southern China. The similarity between fossil and modern fruits shows that during the Middle Miocene the fruit morphological of Lauraceae have changed very little. We also identify families where the fossils we report belong to their closest relatives and can be used to reconstruct the paleoenvironment of Fujian in the Middle Miocene.  相似文献   

6.
《Palaeoworld》2021,30(4):757-769
Here we report a fossil flora from the Miocene Toupi Formation in Jiangxi Province, southeastern China, including megafossil genera Pinus, Podocarpus, Calocedrus, Cinnamomum, Quercus, Lithocarpus, Carya, Palaeocarya, Acer, and Yua. Among them, Yua jiangxiensis n. sp. is the first fossil record of the genus in Asia. A palynological analysis in this study reveals that the palyno-assemblage contains Selaginella, Pteris, Pinus, Picea, Quercus, Fagus, Carya, Ilex, and Rutaceae. Based on Integrated Plant Records (IPR) vegetation analysis, it is suggested that the fossil flora represents an evergreen broad-leaved forest, and the occurrence of tropical and subtropical Cinnamomum supports a warm and moist climate in the region during the middle Miocene.  相似文献   

7.
描述了产自禄丰石灰坝古猿化石地点的三趾马化石,分别归入两个种。其中一个种个体大、上颊齿窝内褶皱复杂且珐琅质厚、马刺呈不对称的多分叉状、次尖呈颈状收缩。根据上述特征组合将其归为西氏三趾马(Hipparion theobaldi (Lydekker, 1877)), 该种在南亚的西瓦里克地区也有分布。另一个种个体小、上颊齿褶皱复杂且珐琅质厚、下颊齿外谷窄而且浅。禄丰这一种与欧亚大陆、非洲和北美的三趾马均有明显差异,故将其定为禄丰三趾马(新种)(Hipparion (Hipparion) lufengense sp. nov.), 该种在西瓦里克地区亦有分布。根据这两种三趾马的齿冠高度及褶皱情况判断,两个种均向适应粗硬食物的方向发展。在这两个种生活的时期里,禄丰以森林环境为主,而西瓦里克地区则向草原化方向发展。因此推断这两个种在积极适应当地环境变化的同时也在为寻求更加适宜的环境进行长距离的迁徙。  相似文献   

8.
9.
New murids of Late Miocene (medial Baodean Chinese Mammal Unit) age from Inner Mongolia, northern China, and from Yunnan Province, southern China, are described. Hansdebruijnia perpusilla nov. sp. represents the earliest known and morphologically most primitive species of the genus, which is known from the latest Miocene of Europe and western Asia. The new species suggests an eastern Palaearctic origin of Hansdebruijnia. “ProgonomysyunnanensisQIU and STORCH, 1990 from Lufeng, Yunnan Province, is referred to Linomys nov. gen. New samples from Leilao, Yuanmou County, Yunnan Province, are included in this species, although this population is somewhat more primitive than that from Lufeng. Leilaomys zhudingi nov. gen. and sp. from Leilao shows a unique combination of apomorphic and plesiomorphic characters, which suggest an early divergence from the murid stem. The new findings indicate that our knowledge of the early radiation of murids in southeast Asia is still in its infancy.  相似文献   

10.
Calophyllum (Calophyllaceae), previously placed in Clusiaceae, is easily recognizable by its opposite entire leaves with close parallel venation alternating with resin canals. However, distinction between species has been difficult, because of infraspecific variation in tepal and stamen number and resemblance among species that share similar habitats. Here, I report the results of multivariate analyses of morphological and anatomical characters for Calophyllum in South America, and provide a taxonomic treatment for the genus in South America, the first since that of Vesque in 1893. Thirteen preliminary morphogroups were identified. Thirty‐two morphological characters of the leaf, flower and fruit from 401 specimens, and 17 anatomical leaf characters from 45 specimens were measured and analysed using principal component analyses (PCAs) and discriminant analyses (DAs). PCAs were used to find groups and DAs were used to validate those PCAs that were potential groups. Two main subgroups were identified in the general analysis. Subgroup M1 has terete stems and smaller leaves and flowers than subgroup M2, which, instead, has quadrangular stems. Only subgroup M2 showed distinctive clusters in regional and local analyses. Distinctive clusters and morphological and anatomical characters helped us to recognize four species in South America, including a new species, Calophyllum pubescens sp. nov. . In addition, a new species, Calophyllum mesoamericanum sp. nov. , is described from Central America. © 2013 The Linnean Society of London,  相似文献   

11.
We studied Upper Cretaceous and Lower Paleogene benthic foraminifera from the Agost section (southeastern Spain) to infer paleobathymetrical changes and paleoenvironmental turnover across the Cretaceous/Paleogene (K/P) transition. Benthic foraminifera indicate uppermost bathyal depths at Agost during the Abathomphalus mayaroensis Biochron (from about 400 kyr before the K/P boundary) through the early Plummerita hantkeninoides Biochron (about 120–150 kyr before that boundary). The depth increased to middle bathyal for the remainder of the Cretaceous, and remained so for the Danian part of the studied section (Parasubbotina pseudobulloides Biochron, at least 200 kyr after the K/P boundary). There were no perceivable bathymetrical changes at the K/P boundary, where 5% of the species became extinct, and the species composition of the benthic foraminiferal fauna changed considerably. Below the boundary, infaunal morphogroups constitute up to 65–73% of the faunas. Directly above the boundary, in the black clays of the lower Guembelitria cretacea Biozone, benthic foraminifera are rare. Several opportunistic taxa (e.g. the agglutinant Haplophragmoides sp.) have short peaks in relative abundance, possibly reflecting low-oxygen conditions as well as environmental instability, with benthos receiving food from short-lived, local blooms of primary producers. Above the clays through the end of the studied interval, epifaunal morphogroups dominate (up to 70% of the assemblages) or there is an even mixture or epifaunal and infaunal morphogroups. Infaunal groups do not recover to pre-extinction relative abundances, indicating that the food supply to the benthos did not recover fully over the studied interval (about 200 kyr after the K/P boundary). The benthic foraminiferal faunal changes are compatible with the direct and indirect effects of an asteroid impact, which severely destabilized primary producers and the oceanic food web that was dependent upon them.  相似文献   

12.
The Early/Middle Miocene boundary locality Sandelzhausen (MN5, southern Germany) yielded three beaver teeth: one lower incisor fragment and two strongly worn upper premolars, a right and a left one. The latter are so similar in wear, height, size, and enamel pattern that they probably represent one individual. Although the teeth have been referred to Chalicomys jaegeri Kaup, 1832 (e.g., Hugueney 1999, Fahlbusch 2003), it seems more likely that they belong to Steneofiber depereti Mayet, 1908. However, the assignment of the present material to either one of these species is difficult, because in the advanced wear stage some diagnostic characteristics cannot be assessed. As to ecological implications for the locality Sandelzhausen the taxonomic identity of these two beaver species may not be important. Both are known from riverine, lacustrine or swamp sediments, and it can be assumed that they usually lived in close vicinity to water. Thus, the presence of beaver remains supports the presence of water at Sandelzhausen. However, the teeth might have an allochthonous origin from creeks of the rising Alps.   相似文献   

13.
The mammal locality of Antonios is one of the few known early-middle Miocene ones of Greece with large mammals. It is situated in Chalkidiki Peninsula (Macedonia, Greece) and includes both small and large mammals. The study of the carnivores found in Antonios indicates the presence of the following taxa: Proputorius cf. P. sansaniensis, Protictitherium gaillardi, Protictitherium cf. P. crassum, Percrocuta sp., Percrocutidae indet. and Pseusaelurus romieviensis. The material of each taxon is described, compared with other material from various Eurasian localities and determined. The species P. cf. sansaniensis and Promieviensis are traced for first time in Eastern Mediterranean, while Percrocuta for first time in Greece. The presence of the other carnivoran taxa in the Antonios fauna is also interesting as they are recognized in older stratigraphic levels enriching our knowledge about their stratigraphic distribution. The carnivores of Antonios cannot offer significant data for the dating of the fauna but its age is discussed using the data coming from the carnivores as well as those from older studies of the micromammals and suoids.  相似文献   

14.
Among the 14 small mammal species from the early Miocene locality of the northern area of the Junggar basin (northern Xinjiang, China), four species are cricetids (Rodentia): unnamed species of Cricetodon and Eumyarion, and two new species, Karydomys debruijni nov. sp. and Megacricetodon beijiangensis nov. sp. Some aspects of the morphology of Cricetodon sp. are shared by Eucricetodon from the late Oligocene, suggesting that these specimens could be of intermediate form between Eucricetodon and Cricetodon. One tooth of Eumyarion sp. was found, making its determination uncertain, but its morphology is clearly differentiated from the one of Cricetodon sp. The species K. debruijni nov. sp. is established based on its primitive features compared to the species known in Europe and Anatolia, and its specific association of characters compared to Karydomys dzerzhinskii. M. beijiangensis nov. sp. shows many plesiomorphic features compared to the species already described in the middle Miocene of China. Based on both the whole assemblage of rodents and the species of cricetids, the biochronologic position and the age of the locality are discussed. The locality appears to be biochronologically very close to the fauna from the Chul’adyr Formation in Aktau Mountains, but we propose an age slightly older than the one proposed for this fauna, probably equivalent to the MN3 biozone in Europe.  相似文献   

15.
From the Bavarian Early/Middle Miocene (MN5) site Sandelzhausen, nine species of carnivoran mammals are identified including the hemicyonine ursid Hemicyon stehlini, the amphicyonids Amphicyon cf. major and Pseudarctos bavaricus, the mustelids Ischyrictis zibethoides and Martes cf. munki, the mephitid Proputorius pusillus, the viverrid Leptoplesictis cf. aurelianensis, the felid Pseudaelurus romieviensis, and finally the recently described barbourofelid Prosansanosmilus eggeri. With these taxa present, Sandelzhausen shows a carnivoran community typical, though deprived, for the Lower to Middle Miocene of Europe, but different from roughly contemporary Mediterranean faunas such as those from Çandir or Pa?alar in Turkey.  相似文献   

16.
滇南红厚壳种子油的脂肪酸成分   总被引:25,自引:0,他引:25  
应用GC-MS联用技术对云南省西双版纳产的滇南红厚壳(Calophyllumpolyanthum)种子油的脂肪酸成分进行分析.检出12种脂肪酸成分,占总量的99.39%,主要是亚油酸(38.75%),棕榈酸(22.42%),油酸(22.11%)和硬脂酸(9.81%).  相似文献   

17.
We studied 344 samples from Well XK-1 in Xisha Islands, South China Sea, and identified 66 species of larger benthic foraminifera, providing critical evidence for biostratigraphy and palaeoenvironmental interpretation of the Miocene reef carbonate sequence. Three assemblages are recognized, namely, Spiroclypeus higginsiBorelis pygmaeus Assemblage (Letter Stage Te5, Early Miocene, 1256.28–1180.15 m), NephrolepidinaMiogypsina Assemblage (Tf, Middle Miocene, 1031.10–577.04 m), and CycloclypeusHeterostegina Assemblage (Tg, Late Miocene, 468.13–380.42 m). On the basis of the palaeoecological preference of the larger foraminifera, we interpret that the Miocene carbonate sequence was deposited mainly in a warm tropical shallow water environment, characterized by five stages of continuous long-term evolution: backreef lagoon to shelf in the Early Miocene, normal to frontal reef in the early Middle Miocene, backreef lagoon to shelf in the later Middle Miocene, normal to frontal reef in the early Late Miocene, and proximal forereef shelf in the later Late Miocene.  相似文献   

18.
The Tabernas Basin in southeast Spain is a Neogene intermontane basin which filled with sub-aerial and submarine fan conglomerates grading into turbidite sandstones towards the basin centre. The basin history involved the development of Seravallian-Tortonian subaerial fans which coalesced southwards from the basin margin. Increasing water depth in the Tortonian led to a submarine development of these fans. The coarse fan conglomerates are colonized almost solely by barnacles of the species Megabalanus tintinnabulum , known from Miocene-Recent deposits. The barnacles occur in seven preservational-state assemblages, which provide a record of the colonization of stabilized mass-flow conglomerates and of subsequent reworking episodes. M. tintinnabulum is known from intertidal environments today. In situ clusters developed on the fan conglomerates record the transition of the fans from subaerial to submarine environments. Mass-flow deposits rich in barnacle shell debris are representative of basin-wards reworking of intertidal clusters and illustrate relative increase in water depth. A further shallowing episode is identifiable by the recolonization of mass flows by in situ barnacle clusters. This case history is demonstrative of the utility of some barnacles in determining basin history with respect to minor sea level fluctuations.  相似文献   

19.
20.
Fossil fruits of Palaeocarya (Juglandaceae) are described from late Miocene sediments of southeastern Yunnan, China. The fruits present a tri-lobed wing consisting of an intact oblong-ovate middle lobe and two lateral lobes. The lobes are apically obovate, and have pinnate venation. The middle lobe is thicker at the base and gradually tapers to the apex. The nutlet, located at the base of the winged fruit, is round and hispid, and is subdivided by a septum into two compartments. Based on extensive morphological comparisons to previously documented fossil fruits, we found that the fossil fruits align most closely with members of the genusPalaeocarya, but have a unique combination of characters. Thus, we describe the fossils as a new species, Palaeocarya hispida sp. nov. This species represents an important range expansion for low-latitude occurrences of Palaeocarya in the late Miocene and therefore substantially improves our understanding of the biogeographic history of the genus. We propose that the wide distribution of Palaeocarya and relatively narrow distributions of close relatives, Engelhardia, Alfaropsis, and Oreomunnea, might be associated with a stepwise cooling and a major ice sheet expansion in the Antarctic and Arctic from the late middle Miocene to early Pliocene. In particular, the climatic oscillations during the Quaternary, such as the last glacial maximum, might have led to a decrease in the geographic distribution of Engelhardieae.  相似文献   

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