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1.
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   

2.
To address the evolution and geographical diversification of the genus Zelkova (Ulmaceae) a phylogenetic analysis of morphological data and the sequences of the internal transcribed spacers (ITS1 and ITS2) of nuclear ribosomal DNA were used. Cladistic analyses suggested that the Chinese species Z. schneideriana and Z. sinica are basal within Zelkova. The western Asian Z. carpinifolia either appears nested between the East Asian Z. schneideriana and Z. sinica and a clade formed by the Japanese Z. serrata and two Mediterranean species, Z. abelicea and Z. sicula (ITS), or forms a clade with Z. serrata that is sister to a clade Z. abelicea plus Z. sicula (morphology). Nucleotide data suggested that gene flow occurred between Z. schneideriana and Z. serrata, and Z. carpinifolia and a lineage ancestral to Z. abelicea/sicula. Character evolution in Zelkova appears to have gone from long leaves with numerous secondary veins, coarse to shallow teeth with blunt or slightly pointed apex and small stomata, to leaves that are either long or short with numerous or few secondary veins, coarse teeth with cuspidate or obtuse apex or conspicuously shallow teeth, and dimorphic stomata displaying ‘giant stomata’ surrounded by a ring of small stomata or uniform large stomata. These results are in agreement with fossil data. Early Cainozoic fossils attributed to Zelkova from North America and Central Asia closely resemble the modern Z. schneideriana and Z. carpinifolia. The genus could have originated in the northern Pacific area and migrated to Europe after the Turgai Strait was closed during the Late Oligocene. Geographical differentiation may have started with the isolation of Chinese populations (leading to modern Z. schneideriana and Z. sinica) from high‐latitude Eurasian (North American) populations. This widespread Early Cainozoic type may have diversified into the western Asian Z. carpinifolia and the more derived Japanese and Mediterranean species during the latest Cainozoic. The modern Japanese and European/western Asian species would have differentiated relatively late, while two locally endemic Mediterranean species are the result of the cooling and development of a Mediterranean climate belt in Europe during the Pleistocene. Fossils from the Miocene and Pliocene of Europe resemble modern Z. carpinifolia and Z. serrata. Differentiation of the two Mediterranean species Z. abelicea and Z. sicula in the Late Cainozoic cannot be traced by leaf morphology. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 147 , 129–157.  相似文献   

3.
Abstract

Three species within the genus Calophyllum collected from middle Miocene Fotan Group sediments in Zhangpu County, Fujian, southeastern China are described in this paper. These fossils include Calophyllum zhangpuensis sp. nov., Calophyllum striatum, and Calophyllum suraikholaensis. The new fossil species C. zhangpuensis sp. nov. is oval, possesses entire leaves with closely spaced parallel secondary veins and has a round, or slightly retuse, apex. These specimens represent the first known fossil records of this relative wide leaf-type form of Calophyllum from China and have a length:width (L:W) ratio less than 3:1. In combination with the known modern geographic distribution and habitats of this wide leaf-type Calophyllum and other plants, data suggest that the middle Miocene Fotan flora is indicative of a warm climate. Thus, based on available fossil data, we speculate that this genus probably originated in India during the Paleocene before spreading from India to Bangladesh and into China, Sumatra, Malaysia, Indonesia, and Java during the Neogene, leading to its modern distribution. At least, the 3 fossil species in this region can explain floristic exchange between India, Fujian, and South China, which is consistent with previous studies; the occurrence of these 3 species indicates that Calophyllum began to diversity in China no later than the Miocene.  相似文献   

4.
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   

5.
Based on morphological and epidermal characters of the leaf, a new species, Ettingshausenia sarbaensis sp. nov., from the Cenomanian-Turonian of western Kazakhstan is described. In fossil Platanus-like leaves, the unique epidermal structure, with the combination of encyclocytic, laterocytic, and paracytic stomata and the presence of trichomes on one or from two to seven epidermal cells, is shown for the first time. Based on variations in morphological and epidermal characters, two morphotypes corresponding to groups of sun and shade leaves are recognized. The expediency of consideration of dispersed Cretaceous Platanus-like leaves within the framework of morphological classification of leaves is discussed.  相似文献   

6.
The ring‐cupped oaks (Quercus subg. Cyclobalanopsis) characterized by united and concentric ring‐cupped acorns, are mainly distributed in broad‐leaved evergreen forests in tropical and subtropical regions of East and Southeast Asia. Their geological history has been traced from the middle Eocene to Pleistocene. Most reports of the subgenus have been on the basis of leaves, whereas the acorns or cupules, more valuable evidence for the inter‐ and intrageneric classifications, have been relatively poorly documented. Here, we describe a new species, Quercus shangcunensis sp. nov., based on a ring‐cupped fossil acorn and pollen on the acorn, as well as Quercus sp. associated leaves, recovered from the early Oligocene Shangcun Formation of Maoming Basin, Guangdong Province, South China. The morphological and anatomical structures of these fossils confirm their attribution to the subg. Cyclobalanopsis. Quercus shangcunensis sp. nov. represents the world's first Oligocene fossil acorn and the earliest fossil acorn in China for the subgenus, indicating that the subg. Cyclobalanopsis arrived in the low latitude area of South China at least by the early Oligocene. Our fossil provides evidence that the subgenus was present in one of its modern distribution centers in the Oligocene, suggesting that the modern distribution patterns of the subg. Cyclobalanopsis most likely originated during or prior to the Oligocene.  相似文献   

7.
Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera.  相似文献   

8.
9.
We present here the earliest known Asian fossil records of the Menispermaceae based on fossil fruits from Paleocene and Eocene localities in South China. A new genus and species, Paleoorbicarpum parvum sp. nov., and two new species of Stephania Loureiro, S. ornamenta sp. nov. and S. geniculata sp. nov., are recognized from Paleocene deposits of the Sanshui Basin, Guangdong, and a new occurrence of the widespread Eocene species Stephania auriformis (Hollick) Han & Manchester is recognized from the Maoming Basin, Guangdong. The Paleocene Stephania specimens described here represent the earliest fossil endocarp record of the Menispermaceae in eastern Asia. This discovery shows that the moonseed family had arrived in tropical and humid South China by at least the middle Paleocene, which provides important evidence for the origin and phytogeographic history of the family.  相似文献   

10.
? Premise of the Study: Calocedrus is among the genera with a typical eastern Asian-western North American disjunct distribution today. The origin of its modern distribution pattern can be better understood by examining its fossil record. ? Methods: The present article reports for the first time a new fossil species of this genus based on compressed material from the Oligocene Ningming Formation of Guangxi, South China, in its present major distribution area in eastern Asia. ? Key Results: Calocedrus huashanensis sp. nov. is most similar to the two extant eastern Asian species, C. macrolepis and C. formosana, in gross morphology of foliage shoots and bears a close resemblance to the latter in cuticle structure. It shows a general similarity to the North American fossil representatives of the genus in alternately branched foliage shoots but is clearly different from the European Paleogene species characterized by oppositely branched leafy shoots. ? Conclusions: This discovery provides new evidence for the floristic exchange of this genus between eastern Asia and North America before the Oligocene (most likely in the Eocene), presumably via the Bering land bridge. The flattened leafy shoots and dimorphic leaves with thin cuticle, open stomatal pits, and shallowly sunken guard cells of the present fossils suggest a rather humid climate during the Oligocene in the Ningming area, South China.  相似文献   

11.
New Ceratopogonidae from the Early Cretaceous amber of Hammana (Central Lebanon) are studied. Five new species (Lebanoculicoides daheri sp. nov., Protoculicoides krzeminskii sp. nov., Archiaustroconops annae sp. nov., Archiaustroconops hammanensis sp. nov., and Archiaustroconops dominiakae sp. nov.) are characterized, described, illustrated, and compared with other Cretaceous taxa. New keys for species of the three genera Lebanoculioides, Protoculicoides, and Archiaustroconops, but also for all genera of Lebanese fossil biting midges, are proposed.  相似文献   

12.
13.
Bees (Anthophila) are one of the major groups of angiosperm-pollinating insects and accordingly are widely studied in both basic and applied research, for which it is essential to have a clear understanding of their phylogeny, and evolutionary history. Direct evidence of bee evolutionary history has been hindered by a dearth of available fossils needed to determine the timing and tempo of their diversification, as well as episodes of extinction. Here we describe four new compression fossils of bees from three different deposits (Miocene of la Cerdanya, Spain; Oligocene of Céreste, France; and Eocene of the Green River Formation, U.S.A.). We assess the similarity of the forewing shape of the new fossils with extant and fossil taxa using geometric morphometrics analyses. Predictive discriminant analyses show that three fossils share similar forewing shapes with the Apidae [one of uncertain tribal placement and perhaps near Euglossini, one definitive bumble bee (Bombini), and one digger bee (Anthophorini)], while one fossil is more similar to the Andrenidae. The corbiculate fossils are described as Euglossopteryx biesmeijeri De Meulemeester, Michez, & Engel, gen. nov. sp. nov. (type species of Euglossopteryx Dehon & Engel, n. gen.) and Bombus cerdanyensis Dehon, De Meulemeester, & Engel, sp. nov. They provide new information on the distribution and timing of particular corbiculate groups, most notably the extension into North America of possible Eocene-Oligocene cooling-induced extinctions. Protohabropoda pauli De Meulemeester & Michez, gen. nov. sp. nov. (type species of Protohabropoda Dehon & Engel, n. gen.) reinforces previous hypotheses of anthophorine evolution in terms of ecological shifts by the Oligocene from tropical to mesic or xeric habitats. Lastly, a new fossil of the Andreninae, Andrena antoinei Michez & De Meulemeester, sp. nov., further documents the presence of the today widespread genus Andrena Fabricius in the Late Oligocene of France.  相似文献   

14.
An ariommatid fish, Isurichthys breviusculus sp. nov. (Perciformes), from the Lower Maikopian (Lower Oligocene) of the northern Caucasus (Apsheronsk District) is described based on an almost complete skeleton. This is the first record of the Oligocene genus Isurichthys in the Caucasus. Direct evidence of the presence of a toothed pharyngeal sac in the oesophagus of Isurichthys is obtained for the first time. Of two known species of Isurichthys, the new species is closer to I. roumanus Baciu et Bannikov, 2004 from the Oligocene of Romania. The fossil record of Stromateoidei sensu stricto is reviewed.  相似文献   

15.
In this paper, we describe a new species Magnolia nanningensis sp. nov., based on exceptionally well‐preserved mummified fossil woods from the late Oligocene of the Nanning Basin, Guangxi, South China. The features of these woods indicate a close affinity to the section Michelia of the subgenus Yulania belonging to the genus Magnolia sensu lato (Magnoliaceae). Magnolia nanningensis is the first fossil record of the section Michelia from China, the modern diversity center of this group. These mummified woods provide fossil evidence supporting molecular dating that estimated an Oligocene age for divergence of the tropical evergreen section Michelia and the temperate deciduous section Yulania. Helical thickenings on vessel walls and a high degree of vessel grouping found in these fossil woods could be adaptive to temporary, possibly seasonal, droughts and, as suggested by other woods from the Nanning Basin, could be indicative of a monsoon‐influenced tropical climate in Guangxi during the late Oligocene. Helical thickenings have not been reported in magnoliaceous fossil woods prior to the Oligocene. The appearance of this trait was presumably a response to abrupt climate cooling near the Eocene–Oligocene boundary, followed by increase in climate seasonality. The associated increase of latitudinal zonation might be a possible trigger for divergence between the tropical evergreen sect. Michelia and the temperate deciduous sect. Yulania.  相似文献   

16.
Abstract: A new family, Pronemouridae fam. nov., with a new genus, Pronemoura gen. nov., and five new species of fossil stoneflies are described from Daohugou village (Middle Jurassic), Inner Mongolia, China: Pshii sp. nov., P. angustithorax sp. nov., P. longialata sp. nov., Pminuta sp. nov. and P. peculiaris sp. nov. Wing venation of pronemourinids presents some or considerable variety in the fore and hind wings of the same or different individuals. Pronemourinidae, retaining plesiomorphic characters (short, multisegmented cerci and CuA with forks), should be treated as the stem group of Nemouridae and Notonemouridae. Based on fossil data, we propose a model in which the extant plecopterid distribution began in the Early Cretaceous. Nemouridae and Notonemouridae must have occurred in Asia and begun to migrate from here by at least the Early Cretaceous.  相似文献   

17.
ABSTRACT

A new fossil species of the genus Scutus (Scutus mirus n. sp.) is described from five Late Oligocene to Early Miocene (Waitakian to Altonian; 25.2–15.9?Ma) localities in the South Island, New Zealand. It is one of the oldest fossil species of Scutus known and probably inhabited very shallow, sub-tropical waters surrounding Zealandia during this time. The holotype of Scutus petrafixus Finlay, 1930 is re-examined; it is possibly from All Day Bay, Kakanui (Waitakian 25.2–21.7?Ma). The New Zealand species documented herein significantly expand our understanding of the fossil record of this shallow-marine molluscan lineage, and by proxy, also indicate the presence of very shallow coastal marine environments around the late Oligocene and early Miocene in southern Zealandia.  相似文献   

18.
Three new species of Mya Linné are described from Greenland. Mya eideri sp. nov. is figured and compared with boreal and fossil species with which it has been confused, and the known distribution of the species is indicated. The validity in Recent faunas of the fossil species M. pseudoarenaria and M. uddevallensis is discussed; two new Recent species, M. neoovata sp. nov. and M. neouddevallensis sp. nov., from Ikka Fjord, southwest Greenland, and Scoresbysund, East Greenland, respectively, are described for Recent material of the comparable two fossil taxa. Accepted: 2 May 1999  相似文献   

19.
本文描述了发现于福建省漳浦地区佛昙群的三宝木属(Trigonostemon)一新种:漳浦三宝木(Trigonostemon zhangpuensis sp. nov. J.L. Dong et B.N. Sun)。该化石叶片呈倒披针形,基部窄,顶端渐尖;中上部的叶缘具细齿,近叶基1/3的部位全缘;叶脉为羽状环曲脉,中脉粗壮,向上逐渐变细;气孔器为无规则型,气孔呈长椭圆形,分布稀疏,无规则排列;平周壁不光滑,具褶皱。化石种与现生种剑叶三宝木(Trigonostemon xyphophyllorides(Croiz.) L.K. Dai et T.L. Wu)在叶片形态特征方面最为相似。剑叶三宝木分布在我国的海南省,基于化石种与最近亲缘现生种的生态幅基本一致的假设,漳浦地区在中新世中期的气候特征可能类似于现今海南省。化石种叶片上共划分13种损伤类型,属于6类功能性取食组,包括孔洞取食(hole feeding)、边缘取食(margin feeding)、留脉式取食(skeletonization)、表面取食(surface feeding)、造瘿(galling)和刺吸式取食(pierci...  相似文献   

20.
A new subfamily of predaceous diving beetles, Liadytiscinae subfam. nov., including two genera and four species, Liadytiscus gen. nov. (L. cretaceus sp. nov., L. longitibialis sp. nov., and L. latus sp. nov.) and Liadroporus gen. nov. (L. elegans sp. nov.), from the Late Tithonian-Berriasian (Huangbanjigou, Yixian Formation) of China is described. Two new genera, Mesoderus gen. nov. with two species, M. magnus sp. nov. and M. ventralis sp. nov., and Sinoporus gen. nov. with one species, S. lineatus sp. nov., are also described; their position in the system of Dytiscidae remains uncertain. Relationships of the taxa described with Recent and fossil taxa of the same rank and some presumable ecological features of the new taxa are discussed.  相似文献   

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