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1.
The Juglandaceae (walnut family) has an excellent fossil record of various organs extending back to the earliest Tertiary. Several genera which today are restricted to isolated geographic regions were widespread in the Northern Hemisphere during the Tertiary. This paper focuses upon the fossil record of the Pterocarya alliance of the subfamily Juglandoideae, tribe Juglandeae. The Pterocarya alliance includes only two modern genera, Pterocarya (five species) and Cyclocarya (one species), both restricted to Eurasia. Paleogene sediments of the Rocky Mountain Region have yielded three genera and four species referable to the Pterocarya alliance: Cyclocarya (two species), Pterocarya, and a new genus, Polyptera. Although three of the four Paleogene species described here are attributed to present day genera, each represents an extinct form, which cannot be accommodated by any single living species. These fossils, reviewed with other published reports, indicate that the Pterocarya alliance, like the Engelhardia alliance of the same family, was more diverse and much more widespread geographically in the Tertiary than it is today.  相似文献   

2.
3.
《Annales de Paléontologie》2019,105(2):119-122
A new fossil species from the Eocene Baltic amber of the extinct tribe Mimoplatycini Kazantsev, 2013 (Cantharidae Malthininae), is illustrated and described here. Mimoplatycis marchettii sp. nov. is characterized by a transverse but interrupted carina in the middle of pronotum. The tribe is known from Baltic and Rovno amber, and the pronotum with carinae similar to Lycidae could be interpreted as mimicry. The pronotal shape is here indicated as a diagnostic character of the species level.  相似文献   

4.
The living fossil Ginkgo, a relict of a once dominant gymnosperm, existed and flourished early in the Mesozoic, but only a vague outline of its evolutionary history in the Tertiary has been unveiled. Here we describe a new species, Ginkgo jiayinensis sp. nov., from the Wuyun Formation of Jiayin, China, which is another well-established Tertiary species based on leaf fossils besides G. adiantoides. The most remarkable feature of the new species is the amphistomatic leaves, likely representing a distinct evolutionary line of the genus in this time interval. Ginkgo jiayinensis is similar to the co-occurring G. adiantoides and extant G. biloba in the lower cuticle, but the two latter species clearly differ in having hypostomatic leaves. Ginkgo biloba is used as the nearest living equivalent (NLE) species for both G. adiantoides and G. jiayinensis in reconstructing paleo-CO(2), as it has been used for other fossil species with either hypostomatic or amphistomatic leaves. The two Tertiary species are almost identical in stomatal index in abaxial cuticles (8.4 and 8.5, respectively), showing no strong differences in response to atmospheric CO(2). Amphistomatic G. jiayinensis would therefore have used a different ecological strategy from that of G. adiantoides of the same bed.  相似文献   

5.
The contribution of nonecological factors to global patterns in diversity is evident when species richness differs between regions with similar habitats and geographic area. Mangrove environments in the Eastern Hemisphere harbor six times as many species of trees and shrubs as similar environments in the New World. Genetic divergence of mangrove lineages from terrestrial relatives, in combination with fossil evidence, suggests that mangrove diversity is limited by evolutionary transition into the stressful marine environment, the number of mangrove lineages has increased steadily over the Tertiary with little global extinction, and the diversity anomaly in mangrove vegetation reflects regional differences in the rate of origin of new mangrove lineages.  相似文献   

6.
A new genus of juglandaceous winged fruit, is described from the Reading Beds (Upper Palaeocene) of southern England. It comprises one of the earlier macrofossil records of the Juglandaceae, and is the earliest from the European Tertiary. The fruit represents an extinct genus related to the extant tribe Engelhardieae, but excluded from it by its simple unlobed bract. Cladistic analysis shows Casholdia to display generalized engelhardioid fruit morphology. It lacks the tri-lobed bract diagnostic of the Engelhardieae, and predates the first occurrence of such bracts in the fossil record. Casholdia adds to the mounting evidence indicating an early Palaeogene radiation of the Juglandaceae.  相似文献   

7.
There are many extant endemic plants in China, which were widely distributed in the North Hemisphere during Tertiary. The global cooling during the Tertiary caused a series of narrow distribution regions of the plants. Quaternary glaciation invaded most regions of North America and Eurasia where severe destruction was imposed onto vegetation. However, such destruction was lessened in China largely because of specific topographic and geographical and obviously, a number of other conditions accounted for an unusual refugee camp for the relics of plants in China, among which lots of endemic taxa exist. Recently, Chinese endemic species, such as Metaseqouia, Eucommia , have been employed to conduct multi-disciplinary comprehensive studies so as to analyze Tertiary climate changes quantitatively. Meanwhile, a rigorous method, i.e. climate analysis of endemic species (CAES) has come to maturation. This method is characteristic of some generality because it is supposed to be applicable to the endemic species in other regions of the world. CAES is involved in the following aspects: 1. Conduct multidisciplinary studies on living and fossil species of endemic plants and trace their evolutionary courses. 2. Compare fossil species with living one and clarify which is the nearest living relative (NLR) to fossil counterpart. 3. Fossils and their living counterparts (NLR) are supposed to have similar ecological requirements to meet their life cycles. 4. Investigate the geographic distribution of living and fossil plants within the same taxa and ascertain the dynamic changes of their distributions in geological age. 5. Analyze climate factors in the distribution of specific endemic taxa and obtain the data of climatic characters which are suitable for reconstruction of paleoclimate where fossil counterparts lived. 6. Further study the physio-ecology of living species and determinate paleoclimate where fossil counterparts lived. 7. Integrate analysis of the data from steps 4, 5 and 6, and quantitatively reconstruct the climate where fossil and living plants survive.  相似文献   

8.
1 全球气候变化研究新动向自 2 0世纪 80年代以来 ,全球气候变化研究至今仍方兴未艾。全球气温波动、大气中温室气体丰度变化、气候格局改变、气候带迁移和降水量增减 ,都影响到社会经济的发展和人类生活质量的提高。各国政府对全球气候变化的研究 ,如气候演变的过程、短期和长期气候变化的预测和自然灾害的防治都给予极大关注和财力支持[1] 。目前全球气候变化的研究正向两个方向发展。1.1 加大全球气候变化研究时间尺度 ,从研究当今气候发展到研究地质历史时期气候变化全球气候变化 ,如大气中CO2 浓度的变化、温度的升降和降水量的变…  相似文献   

9.
The Menispermaceae family (Ranunculales) includes more than 500 extant species. Climbers represent the majority of this family, and these plants are now distributed in all of the tropical and subtropical regions of Americas, Asia and Africa. Their endocarps show a characteristic shape that is easily identified in the fossil floras. Numerous fossil leaves are also mentioned in the literature, but the methods for identifying these fossils are often outdated and need revision. Four tribes of Menispermaceae are present in the fossil record, including Fibraureae, Menispermeae, Pachygoneae and Tinosporeae. Only the Anomospermeae are potentially lacking. The Menispermaceae appear in the Palaeocene, and are common in the Eocene, of Europe and in North America as represented by endocarps and locule-casts. The species of this age show morphological diversification, corresponding with the current familial diversity. A few specimens from the Cretaceous period could be part of this Angiosperm family. Fossils after the Eocene are scarcer, despite several relatively rich outcrops. The maximal expansion of the Menispermaceae during the Palaeocene/Eocene limit correlates with the thermal optimum of the early Tertiary and also parallels the maximal expansion of tropical and subtropical floras. The relative richness of the Eocene era in Menispermaceae could be a consequence of more intense sampling in some regions. The bias in tribe representation can be explained by evolution, ecology or taphonomic hypotheses.  相似文献   

10.
There are many extant endemic plants in China, which were widelydistributed in the North Hemisphere during Tertiary. The global cooling during the Tertiary caused a series of narrow distribution regions of the plants. Quaternary glaciation invaded most regions of North America and Eurasia where severe destruction was imposed onto vegetation. However, such destruction was lessened in China largely because of specific topographic and geographical and obviously, a number of other conditions accounted for an unusual refugee camp for the relics of plants in China, among which lots of endemic taxa exist. Recently, Chinese endemic species, such as Metaseqouia, Eucommia, have been employed to conduct multi-disciplinary comprehensive studies so as to analyze Tertiary climate changes quantitatively. Meanwhile, a rigorous method, i.e. climate analysis of endemic species (CAES) has come to maturation. This method is characteristic of some generality because it is supposed to be applicable to the endemic species in other regions of the world. CAES is involved in the following aspects: 1. Conduct multidisciplinary studies on living and fossil species of endemic plants and trace their evolutionary courses. 2. Compare fossil species with living one and clarify which is the nearest living relative (NLR) to fossil counterpart. 3. Fossils and their living counterparts (NLR) are supposed to have similar ecological requirements to meet their life cycles. 4. Investigate the geographic distribution of living and fossil plants within the same taxa and ascertain the dynamic changes of their distributions in geological age. 5. Analyze climate factors in the distribution of specific endemic taxa and obtain the data of climatic characters which are suitable for reconstruction of paleoclimate where fossil counterparts lived. 6. Further study the physio-ecology of living species and determinate paleoclimate where fossil counterparts lived. 7. Integrate analysis of the data from steps 4, 5 and 6, and quantitatively reconstruct the climate where fossil and living plants survive.  相似文献   

11.
Foliar fossils of Proteaceae are reviewed, and useful specimens for interpreting evolution, and past and present distributions and environments are discussed. There are no definite Cretaceous occurrences. However, there is evidence of extant lineages dating from the Paleocene onwards, including tribe Persoonieae of subfamily Persoonioideae and each of the four tribes of subfamily Grevilleoideae. High diversity and abundance characterizes the Australian fossil record, including sclerophyllous and xeromorphic forms, but there is little evidence of the prominent extant subfamily Proteoideae. New Zealand had a much higher diversity of Proteaceae than at present, including Oligo-Miocene species of open vegetation. The South American leaf fossil record is not extensive. However, the fossil records of Embothrieae and Orites are consistent with the distributions of their extant relatives in South America and Australia being the result of vicariance. Overall, there is a need for more research on placing Proteaceae leaf fossils in a phylogenetic context.  相似文献   

12.
A new genus and species Gordoniopsis polysperma and two new species of Gordonia (Gordonieae, Camellioideae, Theaceae) are described based on fossil fruit and seed remains. These specimens are part of a large flora consisting of various plant organs from the middle Eocene Claiborne Formation in western Kentucky and Tennessee. Gordoniopsis is a five-valved loculicidally dehiscent capsule similar to capsules of Gordonia but differing in having unwinged seeds and a greater number of seeds per locule. The two Gordonia species are among the earliest unequivocal records of the genus and two of only four fossil Gordonia species known with in situ seeds. Two extinct genera, Gordoniopsis and Andrewsiocarpon, and the extant genus Gordonia in the tribe Gordonieae are known from the middle Eocene Claiborne flora, suggesting an early radiation within the tribe. Based on a survey of Recent fruits and seeds we concur with Keng's proposal to merge Laplacea with Gordonia.  相似文献   

13.
Abstract. Badisis ambulans gen.n. et sp.n. is described from flower-inhabiting apterous males. There is a remarkable similarity in structure of abdominal sternite 5 to the Tertiary fossil Electrobata. The relationships of Badisis are discussed and it is referred provisionally to the tribe Metopochetini of the family Micropezidae. A few observations on its habits and ecology are recorded. It is a Batesian mimic of a dolichoderine ant.  相似文献   

14.
A new genus and species of belid weevils, Pleurambus strongylus Poinar and Legalov, n. gen., n. sp. (Coleoptera: Belidae) in the tribe Allocorynini is described from Dominican amber. Belid fossils are quite rare and the new species is the first fossil member of the family from the Neotropics. This discovery suggests that belid diversity in Hispaniola during the Tertiary was higher than at present since no extant belids have been reported from the West Indies.http://www.zoobank.org/urn:lsid:zoobank.org:pub:DF79FF39-634D-4BD7-AD0B-F5FB3BBE1081  相似文献   

15.
The Icacinaceae occur pantropically today, but are well represented by fossil fruits of the warm Early Middle Eocene, when tropical plants that currently occupy low latitudes were more widely distributed in higher latitudes. Members of this family are first known in the Late Cretaceous; however, fossil fruits of tribe Iodeae are quite rare before the Eocene. In this paper we describe the first formally recognized Late Paleocene icacinaceous taxa from western North America. We name two new species of Icacinicarya based on anatomically preserved fruits and establish a new genus, Icacinicaryites, for impressions with a strong similarity to Icacinicarya that lack anatomical preservation. These new records from the Almont/Beicegel Creek flora in North Dakota and several localities in Wyoming, Colorado, and Montana complement records known from the Early Eocene of England and document an increased diversity of Iodeae and related forms in the Paleogene of western North America.  相似文献   

16.
The Ortheziidae (ensign scale insects) is a morphologically well‐defined family. The morphology and occurrence in the fossil record suggests a probable early origin of the family in scale insect evolution. The present phylogenetic analysis – based on 69 morphological characters of female ortheziids, using 39 exemplar Recent species – provides the first analytical assessment of relationships among living genera of the family, as well as the relationships of eight fossil species, based on complete, well‐preserved specimens in amber. Monophyly of the subfamilies Newsteadiinae, Ortheziinae and Ortheziolinae is supported, but Nipponortheziinae is found to be paraphyletic by inclusion of the Ortheziolinae. Thus, the subfamily Ortheziolinae is reduced in rank to tribe Ortheziolini stat.n. , which now includes Matileortheziola Kozár & Foldi, Ortheziolacoccus Kozár, Ortheziolamameti Kozár and Ortheziola?ulc. Consequently, the tribes Matileortheziolini, Ortheziolacoccini and Ortheziolamametini are synonymized ( syn.n. ) here under Ortheziolini. Five new species and one new genus of fossil ensign scales are described from three amber deposits: Burmorthezia gen.n. with type species Burmorthezia kotejai sp.n. and also B. insolita sp.n ., both in mid‐Cretaceous Burmese amber (98 Ma) and Arctorthezia baltica sp.n. in Eocene Baltic amber (c. 43 Ma) based on second‐instar nymphs; Mixorthezia kozari sp.n . and M. dominicana sp.n . in Miocene Dominican amber (c. 17 Ma) based on adult females. Fossil placements are unambiguous, with Burmorthezia forming a stem to crown‐group (Recent and Tertiary) Ortheziidae. A summary of described fossil ortheziids is provided.  相似文献   

17.
The paper describes a new species of fossil wood of Euphorbiaceae, Mallotoxylon cleidionoides sp. nov. from the Tertiary Laterites near Santiniketan, Birbhum District of West Bengal. The structure of the fossil wood closely resembles the wood anatomy of the extant genus Mallotus Lour. This is the first record of the occurrence of an euphorbiaceous wood from the Tertiary of West Bengal.  相似文献   

18.
豆科黄华族植物地理学的初步研究   总被引:3,自引:1,他引:2  
在系统学业伦和地理分布及古植物学资源的基础上,利用形态-地理学的原理和方法,对豆科Papilionaceae黄华族和Tribe Thermopsideae进行了植物地理学的初步研究。结果表明,(1)黄华族可能是古地中海起源的,它的起源地在古北大陆的南岸,大约相当于现在的中纬度地区;(2)起源时间能早于第三纪,大约处白垩纪末和始新世之间。当时有一个所谓的“北热带植物群”Boreotropical Flora发生;(3)本族6个属基本上构成一个比较自然的单元。它们是由原始槐族类祖先演化而来的;(4)木本类是本族原始的,早出的类群,它们基本上处于遗状态;草本类是本族进化的、晚出的类群,们种类多,分布区有扩大的趋势;(5)Thermopsis间断分布于亚洲(包括中亚和东亚)、北美(包括北美东部和北美西部。东亚太平洋沿岸和北美大西洋沿岩最有可能是它的原始保存地,而不是起源地,它们主要是通过古地中海海道而发生联系的,造成原始类群星散分布的格局不是由一次,而是多次地史和气候变化的结果;(6)晚第三纪亚洲腹地造山运动引起的喜马拉雅山的降起和青藏高原的抬升,以及北美落基山山体抬升引起的水温条件的急剧变化是某些类群(包括Piptanthus和Thermopsis)物种局部分化的主要动力。  相似文献   

19.
The cupressaceous genus Tetraclinis is recognized from the Oligocene and Miocene of western North America on the basis of co-occurring seed cones, seeds, and foliage branches. Morphological and anatomical comparisons with the two previously recognized European Tertiary species indicate that the North American specimens are morphologically inseparable from Tetraclinis salicornioides (Unger) Kvacek. The North American taxon is treated as a new variety, T. salicornioides (Unger) Kvacek var. praedecurrens (Knowlton) comb. et stat. nov., and is distinguished from the European representatives, T. salicornioides (Unger) Kvacek var. salicornioides, by slight anatomical differences in the leaf epidermis. Although cones and seeds of the fossil species are closely similar to those of extant Tetraclinis articulata, the foliage is more "spreading," composed of flattened segments with fused facial and lateral leaves that are apparently adaptive for a more mesic climate. The recognition of T. salicornioides in western North America along with the absence of Tetraclinis in the fossil and recent flora of eastern Asia provide evidence for communication of the species across the North Atlantic during the early or middle Tertiary.  相似文献   

20.
Anacolosidites Cookson & Pike, a fossil pollen genus recorded since the Campanian, is peculiar in its morphology – six‐porate with three apertures on each hemisphere, located away from the equator, and with the distal and proximal apertures positioned over each other. Representatives of this fossil genus are widely considered to represent extant Olacaceae from tribe Anacoloseae. Olacaceae is an exclusively tropical angiosperm family with a pantropical distribution; consequently the fossils are often used to suggest a tropical climate and in addition are frequently used as a stratigraphic marker. Fossil species assigned to Anacolosidites are quite variable and may not all represent Olacaceae, in which case they may not indicate tropical climate.

The present study is a morphological survey of fossil pollen assigned to Anacolosidites; it identifies the published reports of the fossil species that probably represent positive occurrences of Olacaceae pollen in the fossil record. Within Olacaceae, Anacolosidites‐type pollen is usually compared with pollen of genera in tribe Anacoloseae, in particular: Cathedra, Anacolosa and Phanerodiscus, but never with the pollen of Ptychopetalum, a genus from tribe Olaceae with closely similar pollen to the other three genera, but with a reticulate tectum and very small circular apertures located near the equator. Nevertheless, the records of reticulate Anacolosidites species which have been excluded from the emended diagnosis are unlikely to be related to Ptychopetalum. The earliest accepted record of Anacolosidites is from the Late Cretaceous (Maastrichtian) of Germany. However, most Late Cretaceous records, and later Russian and Chinese occurrences referred to Anacolosidites, consist mainly of Normapolles‐type pollen, whereas many of the Cenozoic records assigned to Anacolosidites have a much clearer affinity with the pollen of Anacolosa, Cathedra and Phanerodiscus (tribe Anacoloseae). The newly emended genus Anacolosidites may be used as a stratigraphic marker for tropical or megathermal climatic conditions.  相似文献   

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