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1.
对浙江天台中新统下南山组6块叶片压型化石——天台润楠Machilus tiantaiensis Ding S. T. et Sun B. N. sp. nov.,并对其叶结构和表皮构造特征进行了详细的研究.其主要特征为:叶椭圆形,全缘,顶端渐尖,基部楔形,侧脉羽状;表皮细胞垂周壁浅波状,单细胞毛基多集中于脉络区;气孔下生式,气孔器短平列型,副卫细胞1~2个.通过与现生植物进行对比分析,发现当前标本的叶结构和表皮构造特征与樟科润楠属(Machilus)十分一致.利用PAST(palaeontological statistics)软件对我国润楠属68种植物叶片的形态特征进行聚类分析,结果表明当前化石与M. pingii Cheng ex Yang最为接近;角质层分析也表明二者的表皮构造最为相似.利用化石与其现存最近亲缘种M. pingii的气孔比率,恢复了天台晚中新世的古大气CO2体积分数为407.9×10-6.此外,依据现生润楠属主要分布于亚洲东南部和南部的热带、亚热带地区,推断天台地区中新世的古气候较为温暖湿润.   相似文献   

2.
The present paper reports two new species of Buxus from the Oligocene Ningming Formation of Guangxi, South China, on the basis of several compressed fossil leaves. Buxus ningmingensis sp. nov. is characterized by an elliptic to ovate shape; pinnate venation with marginal secondary, long hairs on the adaxial side of the midvein base; and amphistomatic, anomocytic stomata with a prominent outer ring. All of these characteristics suggest a closest af?nity to the living Buxus microphylla subsp. sinica. Another new species identi?ed as Buxus preaustro-yunnanensis sp. nov. is characterized by the diagnostic formation of its admedially branched tertiaries, the trunks of which are often strongly thickened by sclereides. This species is most similar to the extant Buxus austro-yunnanensis. The co-occurrence of Buxus ningmingensis sp. nov. and Buxus preaustro-yunnanensis sp. nov. suggests that these two Buxus lived during the Oligocene under a warm, tropical to subtropical climate, similar to the current climate of Ningming. Our ?ndings provide the earliest fossil evidence of Buxus leaves with detailed illustrations of leaf architectural and cuticular features. The occurrence of these two species indicates that Buxus began to diversify in Guangxi no later than the Oligocene.  相似文献   

3.
This study reports a new fossil leaf of Kleinhovia L., Kleinhovia bikanerensis sp. nov., from the Eocene clay mine of the Marh Formation of Bikaner, Rajasthan. The leaf resembling Kleinhovia hospita L. of the family Malvaceae is described for the first time from India. The leaf is characterized by very wide ovate shape, basal actinodromous venation with seven primary veins and cordate base. The presence of this leaf fossil indicates tropical warm and humid climatic conditions prevailing in the area during the Eocene and throws light on its past and present distribution.  相似文献   

4.
Extant Asplenium is one of the most widespread fern groups and occurs in the temperate and tropical regions. However, the fossil records of this genus are poorly documented, especially in the low latitudes. Here, a new species, Asplenium sanshuiense sp. nov. is described from the early Eocene of Sanshui Basin, Guangdong Province, South China. This is the lowest modern latitude fossil record of Asplenium and the first fossil assignment of A. section Darea (Jussieu) Bak., as well as the first fossil record of Asplenium reported from South China. This new species shows that Asplenium had already spread into South China by the early Eocene and the section Darea (Jussieu) Bak. was identifiable within the genus Asplenium during that time. This new species, combined with previous fossil spore-pollen records indicates a warm and humid climate in the Sanshui Basin of the early Eocene.  相似文献   

5.
Albizzia is a leguminous genus belonging to the subfamily Mimosoideae with approximately150 modern species,widely distributed in the tropical and subtropical regions of Asia,Africa,Australia and America.Among them,17 species are mainly distributed in southern and southwestern China.Abundant fossils of the subfamily Mimosoideae,including leaves,pods,flowers and wood,have been reported from the Cretaceous and Paleogene strata of the Northern Hemisphere.However,Neogene records of Mimosoideae are relatively scarce.In this study,fossil pods and leaves belonging to the genus Albizzia from the Bangmai Formation of Yunnan,China were described.They were assigned to three species,including Albizzia scalpelliformis Guo,Li and Xie Emended,Albizzia cf.kalkora(Roxb.) Prain and Albizzia sp.The occurrence of Albizzia fossils from Lincang not only gives important information on the Neogene plant diversity from Yunnan—a worldwide famous biological hotspot—but also provides additional evidence for its phytogeographic history.  相似文献   

6.
New Mesozoic Mesopsychidae(Mecoptera)from Northeastern China   总被引:2,自引:2,他引:0  
<正>The Mesozoic family Mesopsychidae Tillyard,1917 presently consists of seven described genera and 13 species from the mid-Triassic to the Early Cretaceous of Australia,South Africa and Eurasia.In the present paper one new genus and three new species of fossil mesopsychids are described that add significant distributional and stratigraphic extensions to the family.This finding documents the first formal record of fossil Mesopsychidae in China.Both Lichnomesopsyche gloriae gen.et sp.nov.and L.daohugouensis gen.et sp.nov. were found from the Middle Jurassic Jiulongshan Formation of Inner Mongolia,whereas Vitimopsyche kozlovi sp. nov.,of mid Early Cretaceous age,was collected from the Jehol Biota of northern Hebei Province.This new,well-preserved material from China reveals complete and previously unknown body features,including head, antennae,mouthparts,legs and abdomen.The delicate and long proboscides of these new taxa indicate that they were feeding on externally exposed,nutrient-rich fluids of gymnospermous ovulate fructifications,and incapable of piercing surface epidermis-attributable principally to the absence of stylets.These proboscides originated, perhaps multiply,among basal Mecoptera and are functionally and structurally convergent with equivalent mouthparts borne by fossil and extant Diptera,Lepidoptera,Neuroptera and Coleoptera.  相似文献   

7.
《Gondwana Research》2014,25(1):214-225
Jurodidae are thought to be some of the world's most mysterious beetles and display an intriguing mixture of characters occurring in three different suborders. Hitherto, all known fossil and extant Jurodidae were extremely rare and restricted to Russian Siberia and the Far East. Here we describe two new species, Jurodes daohugouensis sp. nov. and Jurodes pygmaeus sp. nov. from the Middle Jurassic of Daohugou, China. A key to all species of Jurodidae and their research history are given, and the detailed morphology of fossil Jurodidae is also presented. Our results confirm the presence of three ocelli in fossil Jurodidae, and reveal that hind wings of J. pygmaeus sp. nov. possess well developed radial and oblong cells, and are very similar to those of extant Jurodidae (Sikhotealinia zhiltzovae). Male genitalia of fossil Jurodidae were described herein for the first time, showing a basal trilobate structure. The presence of exposed propleuron, three pairs of external trochantins, metanepisterna with ridges, primitive characters of wing venation further support the probable placement of Jurodidae in the suborder Archostemata. J. daohugouensis and J. pygmaeus are very similar to S. zhiltzovae in having the big protruding eyes, elevated median portion of frons bearing three ocelli, pubescent body, contiguous procoxae, exposed trachantion of all coxae, elytra with rows of punctures, and wing venation. Our results show that these key characters of extant Jurodidae can be traced back to the Middle Jurassic, revealing that the family has been in a period of evolutionary stasis for at least 160 million years. Furthermore, our discoveries widen the paleogeographic distribution of fossil Jurodidae from Russian Siberia to northern China.  相似文献   

8.
A new Quercus (Fagaceae) morphospecies is described based on well-preserved fossil leaves.The fossils were collected from Yangyi Formation of the Upper Pliocene at the Yangyi coalmine,Baoshan,western Yunnan,China.Details of the microstructure of mesophyll tissue are preserved because lithification of the fossils was not complete.The fossil laminas possess typical characteristics of Quercus sect.Heterobalanus:quite thick and coriaceous cuticle; secondary veins bifurcating near the margin in the middle and top of the leaf; and upper epidermis with adaxial hypodermis.Based on a detailed morphological and anatomical comparison with all living and fossil species of Quercus sect.Heterobalanus,the fossil leaves prove to be different in their sparse and garland-shaped multicellular trichomes on the lower epidermis,and so it is described as a new species Quercus yangyiensis He,Li et Sun sp.nov.The much sparser trichomes of our fossils compare well with those of living Quercus sect.Heterobalanus and indicate a more humid climate during the deposition of the Yangyi Formation in the Late Pliocene.  相似文献   

9.
A new genus and two new species of fossil Fuziidae are described and illustrated: Parvifuzia gen. nov., P. marsa sp. nov. and P. brava sp. nov.. Both species were collected from the Middle Jurassic Jiulongshan, Formation of Daohugou, Inner Mongolia of China. In conjunction with Fuzia Vr?ansky, Liang et Ren, 2009, the present findings allow us to demonstrate that members of the family were morphologically diverse, with body length ranging from medium (17 mm) in Fuzia to small (9.7 mm) in the present genus. Wing venation of F. dadao is complicated, but simple in the present species, and apex of male’s cerci are sharp and forceps-like in F. dadao, but strongly curved inward and round in the new genus.  相似文献   

10.
A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The fossil plant-beating bed belongs to the lower part, the Zhuanchengzi bed, of the Upper Jurassic Yixian Formation (Yixianian). The new genus in leaf shape, venation and epidermal structure shows a transitional form between Mesozoic Cycads (Ctenis, Nilssonia) and modem Cycads (Stangeria and Encephalartos). Since the features of these specimens differ from any known genera of Cycads, a new generic name Yixianophyllum is proposed for these leaves. Typical species, Yixianophyllum jinjiagouense gen. et sp. nov. is described here. A supposed evolutionary tendency of Cycadean leaf-forms with Taeniopteris-type is discussed.  相似文献   

11.
A new species of Meropeidae (earwigfly) is described and figured based on an exceptionally well-preserved individual in mid-Cretaceous amber from Myanmar. Burmomerope clara Zhao and Wang, sp. nov. is distinguished from the type species B. eureka Grimaldi and Engel, 2013 by presence of broader wings with six longitudinal veins in radial sector and seven in medial field, CuA with two terminal branches, and long setae on the anterior margin of the wing. A detailed comparison of the forewings venation in all fossil and extant species is given. The new find is the third fossil species of Meropeidae and also the first fossil female to be described. The female genital structure of B. clara sp. nov. is remarkably similar to that of extant species, revealing 100 million years of morphological conservatism, and thus highlighting the antiquity of the group.  相似文献   

12.
角质层微细构造特征是化石植物鉴定的重要依据,实验研究了云南腾冲新近系樟科润楠属薄叶润楠Machilus leptophylla和长梗润楠(近似种)Machilus cf. longipedicellata两个化石种的表皮微细构造特征,并与现存对应种类进行了表皮构造和叶结构特征的对比分析,补充证实了两化石种均属于自然分类属性。丰富了我国樟科润楠属化石记录。鉴于大气CO2浓度与植物叶片气孔指数呈负相关关系,Machilus叶片可以作为大气CO2浓度的生物指示器。研究表明,利用该类化石叶片气孔参数可推测地史时期古大气CO2浓度,揭示了新近纪滇西地区为温暖湿润性气候。  相似文献   

13.
Sixteen liverwort specimens collected from the Lower Cretaceous Yixian Formation of Huangbanjigou Village, Liaoning Province, China are studied in this work. The plants are thalloid and preserved in brown arenaceous mudstone as impressions. Based on examinations, the liverworts are assigned to two new genera and five new species: Riccardiothallus palmata sp. nov., Pallaviciniites stricta sp. nov., Pellites latithallus gen. et sp. nov., Conocephalumites hexagonites gen. et sp. nov. and Metzgerites multifidus sp. nov., belonging to five families and five genera. The fossil research indicates that the divergence of families, Aneuraceae and Metzgeriaceae, Pallaviciniaceae and Hymenophytaceae, Pelliaceae and Fossombroniaceae, was in the Lower Cretaceous (125 Ma). The research provides significant additions to the fossil liverwort records in Western Liaoning and offers fossil evidence for studying the classification and evolution of extant liverworts.  相似文献   

14.
Sphenopteris(楔羊齿属)叶化石在全球晚古生代地层中广泛出现,但该属的系统分类位置及演化特征仍有待深入探讨,而且只有极少数种的表皮及气孔微细构造得到揭示。笔者在甘肃永昌乌拉尔统山西组中发现了2种形态保存较好且具有角质层的楔羊齿,分别是 Sphenopteris yongchangensis sp. nov.(永昌楔羊齿—新种)和Sphenopteris nystroemii (弱楔羊齿)。前者小羽片呈扇形,基部连合,侧脉分叉1次,气孔作椭圆状且为两面生; 后者小羽片呈梭形且顶端钝圆,侧脉分叉1次并达缘,气孔分布于脉间区。经对比,文中报道的2种楔羊齿可能属皱羊齿目(Lyginopteridales)。此外,统计了Sphenopteris在晚古生代的269个化石记录,结合该属的形态学、解剖学特征和分布记录,探讨了其多样性演化和古地理分布,结果表明: 宾夕法尼亚亚纪至乌拉尔世,Sphenopteris广泛分布于全球中低纬度地区,呈现出高度变异和分化; 自晚泥盆世至二叠纪,Sphenopteris型叶化石在中国自华南向华北迁移演化,说明其多样性特征不仅与湿润气候密切相关,而且与其古地理分布相耦合。  相似文献   

15.
A new genus and new species, Longilanceolatus tenellus gen. et sp. nov., is described and assigned to the tribe Vetanthocorini of the fossil family Vetanthocoridae. In addition, a new species, Curvicaudus spinosus sp. nov., is also described. All specimens were collected from the Lower Cretaceous of the Yixian Formation at Huangbanjigou, Chaomidian Village, Beipiao City, Liaoning Province, northeastern China. Body size, ovipositor length, abdomen length, and other characters of eleven genera from the Middle Jurassic to Eocene are summarized. Comparison of body size of all specimens in the Vetanthocoridae and Anthocoridae (sensu lato) indicate a general trend toward smaller body size through their evolution. Moreover, Longilanceolatus, with uniquely long ovipositor, is related to a different type of oviposition compared with extant flower bugs.  相似文献   

16.
云南临沧晚中新世槭属叶片和翅果研究   总被引:1,自引:0,他引:1       下载免费PDF全文
云南省是研究我国植物多样性,植物区系演化及被子植物迁徙路线的有利场所。文中鉴定并描述了采自云南临沧上中新统邦卖组的槭属(Acer)8块叶片和17块翅果化石,共鉴定为4个种,其中包括1个新种和1个相似种,分别为Acer lincangense sp.nov.和Acer cf.jingdongense。槭属化石在云南邦卖组的出现,证明了该植物群具有北温带和古热带的混生特征,反映了当时植物区系类型的多样化构成了云南现代植物多样性的基础。另外,通过对Acer全球大化石记录以及现生种的统计,总结得出槭属的地史演化具有3个发展高峰期:依次为始新世、中新世和全新世,从古至今呈现一种螺旋式递增趋势。  相似文献   

17.
A new genus with a new species, Sinohelorus elegans gen. et sp. nov., is described and assigned to the subfamily Mesohelorinae, Heloridae. In addition, two new species, Gurvanhelorus beipiaoensis sp. nov. and Spherogaster saltatrix sp. nov., are also described. The diagnoses of Gurvanhelorus Rasnitsyn, 1986 and Spherogaster Zhang and Zhang, 2001 are emended based on new materials and findings. These well-preserved specimens were collected from the Jehol Biota, Early Cretaceous Yixian Formation of Huangbanjigou Village in Liaoning, China. These new species broaden the diversity of this family and enhance our understanding of evolutionary trend of helorid’s metasomal structure, antenna, and forewing venation from the Middle Jurassic to extant.  相似文献   

18.
Leaf fragments of Herbifolia antiqua A. Frolov et Enushchenko gen. et sp. nov. from the Middle Jurassic (Aalenian) of the Irkutsk Coal Basin (Eastern Siberia, Russia) are reported. The following features are characteristic of H. antiqua gen. et sp. nov.: the presence of leaf sheaths, linear smooth-edged leaves with parallel venation, anastomoses between the veins, anomocytic stomata, rhomb-shaped ordinary epidermal cells. Such a combination of characters is widespread in modern monocotyledonous plants and is absent in fossil and modern cryptogam and gymnosperms. Due to the lack of evidence of an enclosed ovule in H. antiqua gen. et sp. nov.we attribute it to a typological angiosperm, based on its unique leaf structure characteristic of monocotyledons. The leaf epidermal structure of Herbifolia gen. nov. is most similar to those of modern Asparagales and Liliales.  相似文献   

19.
In Europe, fossil fruits and seeds of Rhodoleia (Hamamelidaceae) have been described from the Upper Cretaceous to the Miocene, whereas no fossil record of Rhodoleia has been reported in Asia, where the modern species occur. Herein, 21 fossil leaves identified as Rhodoleia tengchongensis sp. nov. are described from the Upper Pliocene of Tengchong County, Yunnan Province, Southwest China. The fossils exhibit elliptic lamina with entire margins, simple brochidodromous major secondary veins, mixed percurrent intercostal tertiary veins, and looped exterior tertiaries. The leaf cuticle is characterized by pentagonal or hexagonal cells, stellate multicellular trichomes, and paracytic stomata. The combination of leaf architecture and cuticular characteristics suggests that the fossil leaves should be classified into the genus Rhodoleia. The fossil distributions indicate that the genus Rhodoleia might originate from Central Europe, and that migrated to Asia prior to the Late Pliocene. Additionally, insect damage is investigated, and different types of damage, such as hole feeding, margin feeding, surface feeding, and galling, are observed on the thirteen fossil leaves. Based on the damage frequencies for the fossil and extant leaves, the specific feeding behavior of insects on Rhodoleia trees appears to have been established as early as the Late Pliocene. The high occurrence of Rhodoleia insect herbivory may attract the insect-foraging birds, thereby increasing the probability of pollination.  相似文献   

20.
A new genus and species, Rebouliothallus huolinhensis sp. nov., and two uncertain species, Ricciopsis sp. and Hepaticites sp., are described. The fossils were collected from the Lower Cretaceous Huolinhe Formation of Huolinhe Basin, northeastern China. The new genus Rebouliothallus was established in the Aytoniaceae family of Marchantiales. Rebouliothallus huolinhensis appears to be quite similar to species of the extant genus Reboulia Raddi. The species is characterized by the relatively large ventral scales. Ventral scales are large, imbricate and arranged in two rows on the ventral surface. Rhizoids are either pegged or smooth. Ricciopsis sp. is characterized by the rosette-forming thallus. Hepaticites sp. shows some similarities to liverworts. Of the forty-nine Early Cretaceous floras of China, only two floras, one from the Huolinhe basin, Inner Mongolia and the other from the Jixi Basin, Heilongjiang Province, contain fossil liverworts. The rare fossil liverwort records in the Early Cretaceous floras of China may be the result of taphonomic bias.  相似文献   

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