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1.
广西宁明第三纪类黄杞翅果化石   总被引:2,自引:0,他引:2  
广西宁明西南约4km处新发现的一个植物群中,含有一些与胡桃科黄杞属现生种的翅果在形态上近似的化石。它们的果翅三裂,裂片具有羽状脉序。这些化石的一部分特征与黄杞属的裸果黄杞组的相似,另一部分特征与该属的黄杞组的相似,因而难以将它们归于其中的任何一组,作者将其归于类黄杞属。后者是胡桃科黄杞族的一个器官属,与目前分布于我国长江以南及东南亚地区的黄杞属以及分布于美洲新大陆的美黄杞属有密切亲缘关系。在地史时期,类黄杞属的代表较广泛地分布于北半球。然而,当前化石却是这类化石在我国南方首次被发现,这为探讨黄杞族的演化提供了重要线索。从当前化石的研究和有关文献中得知,黄杞族祖先的翅果形态与裸果黄杞组的现生种可能有某种程度的近似。  相似文献   

2.
    
The Ventilago Gaertn. (Rhamnaceae) is widely distributed in pantropical areas of Africa, Asia, and Australia. However, fossil records of this taxon are sparse, which limits understanding of the evolution and biogeographic history of the genus. In the present study, we report and describe two new fossil species of Ventilago, V. siwalika sp. nov. from the Miocene sediments of Himachal Pradesh, western Himalaya, and V. pliocenica sp. nov. from the Pliocene sediments of Jharkhand, eastern India based on single-winged samaras. Ventilago pliocenica is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins, the presence of equatorial rim, the hypanthium, and short pedicel. On the other hand, V. siwalika is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins. Our discovery represents the first unambiguous fossil record of single-winged samara of Ventilago from India and provides valuable insights into the evolution of this genus. In this paper, we also review its biogeographic history and add new information to understand its hypothetical migration route. Present and earlier records of Ventilago also suggest that this genus was a common forest element during Neogene (Miocene time) in Asia.  相似文献   

3.
    
《Journal of Asia》2020,23(3):762-771
In situ preservation of fossil insect damage in plant fossils is an excellent tool to study the coevolution of flora and fauna through geological time, but finding both damage and the insect causing that damage in the same specimen is a very rare phenomenon. Galling is a common form of angiosperm leaf damage, which can be regarded as a kind of extended phenotype of the causal insects, essentially the gall midges, but galls usually lack remains of the insects themselves. Here we report the in situ occurrence of a gall midge (Insecta, Diptera, Cecidomyiidae) as well as its pupal exuviae on the abaxial cuticular surface of fossilized leaf cuticle fragments of Fabaceae leaves (cf. Albizia) that also bear galls, recovered from the latest Neogene (Rajdanda Formation, Pliocene) sediments of the Chotonagpur Plateau, Jharkhand, northeastern India. This Pliocene gall midge features well-preserved legs, segmented antenna with distinct and enlarged scape, elongate curved setae, and longer than broad terminal plate of the ovipositor lamellae. The in situ presence of a gall midge on a host fabaceous leaf cuticle indicates the existence of a host-ectoparasite relationship in the ancient warm and humid tropical monsoon-influenced forests of eastern India during the Pliocene. This is the first authentic fossil record of an in situ phytophagous insect of Cecidomyiidae from India, as well as southeast Asia. Although the identification of the recovered phytophagous insect associated with the fossil leaf cuticle is only possible to family level, this find reveals that such plant-insect relationships existed in the Pliocene of eastern India.  相似文献   

4.
    
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   

5.
国产赖草属3组植物叶表皮解剖特征及其系统关系   总被引:1,自引:0,他引:1  
采用徒手刮削法对国产赖草属中多穗组、少穗组和单穗组主要代表种的叶表皮微形态特征进行了观察。结果显示:(1)赖草属3组植物的叶表皮皆由长细胞、气孔器细胞、短细胞和刺毛组成,表现为典型的狐茅型;同时,3组植物在长细胞的长度与宽窄,气孔器的大小与分布及副卫细胞的形状,短细胞的丰缺与着生形式,刺毛的数量、体积与类型等性状上存在明显差异。(2)根据3组植物叶表皮性状的演化趋势,对各组的演化关系和系统位置分析表明,多穗组最原始,少穗组较进化,单穗组最高级;多穗组可能直接派生了较进化的少穗组,并在少穗组的基础上进而产生了最高级的单穗组。多穗组、少穗组和单穗组的这一系统关系与利用外部形态特征所获得的演化趋势基本一致。  相似文献   

6.
苏旭  刘玉萍  陈克龙 《植物研究》2012,32(2):129-136
观察了披碱草属中小颖组、宽颖组和长颖组主要代表种的叶表皮形态学特征,总结了3组植物叶表皮结构的异同,探讨了叶表皮特征的分类学意义。同时,根据3组植物叶表皮性状的演化趋势,分析了各组的演化关系和系统位置。结果表明,小颖组最原始,宽颖组较进化,长颖组最高级;小颖组可能直接派生了较进化的宽颖组,并在宽颖组的基础上进而产生了最高级的长颖组。小颖组、宽颖组和长颖组的这一系统关系与利用外部形态特征所获得的演化趋势基本一致。  相似文献   

7.
通过对披碱草属中小颖组、宽颖组和长颖组种类外部形态的观察,总结了3组植物外部形态特征的异同,探讨了形态学特征的分类学意义。同时,根据3组植物外部形态性状—花序、小穗、小花、以及内稃的演化趋势,分析了各组的演化关系和系统位置。结果表明:小颖组最原始,宽颖组较进化,长颖组最高级;小颖组可能直接派生了较进化的宽颖组,并在宽颖组的基础上进而产生了最高级的长颖组。此外,本文对披碱草属参试种的系统关系也作了一定程度的探讨,结果显示圆锥披碱草最原始,墨西哥披碱草最进化,其余参试种居于两者之间。上述研究工作为整个披碱草属系统与进化方面的探讨提供了形态学方面的理论证据。  相似文献   

8.
为探讨山茶属茶亚属(Camellia subgen.Thea)中长柄山茶组(sect.Longipedicellata)、金花茶组(sect.Chrysantha)和超长柄茶组(sect.Longissima)的系统位置和亲缘关系,本研究选取了该属4个亚属11组28个种及2个外类群的材料,对这些材料的叶绿体4个DNA片段(rp/16、psbA-trnH、trnL-F和rp/32-trnL)进行了测序,运用邻接法(neighbor-joining)、最大简约法(maximum-parsimony)和贝叶斯推断(Bayesian inference)对获得的序列进行了联合矩阵分析.并构建基因树.基因树的拓扑结构显示:1)金花茶组包括3个平行的支系,并且长柄山茶组的模式种长柄山茶(Camellia longipedicellata)嵌于其中一个支系,因而金花茶组可能是一个并系或多系类群;2)长柄山茶与越南分布的金花茶组种类在分子系统树上构成一个单系支,暗示了长柄山茶组和金花茶组之间可能具有紧密的亲缘关系;3)超长柄茶组不是一个单系类群,该组的河口超长柄茶(C.hekouensis)位于系统树的基部,与山茶属其余种构成姐妹群.由于缺乏更广泛取样的分析,超长柄茶在山茶属中的系统位置仍然不明确,超长柄茶组与长柄山茶组的亲缘关系问题也没有得到解决.  相似文献   

9.
张树仁 《西北植物学报》2004,24(11):2089-2091
《中国植物志》中记载的薹草属高秆薹草组包括区别显著的两类植物,一类具有间断的穗状花序和叶状苞片,另一类穗状花序紧密、苞片鳞片状或刚毛状,宜分为两个不同的组:高秆薹草组和卵形薹草组。文中将高秆薹草组和卵形薹草组与近缘的薮薹草组进行了形态学比较,并提供了中国高秆薹草组和卵形薹草组的分类纲要。  相似文献   

10.
    
Cyperaceae are a cosmopolitan Monocot family comprising about 5,700 species divided into two subfamilies: Cyperoideae and Mapanioideae. Within Mapanioideae, Mapania is the largest genus, with about 90 species. Anatomical studies on Mapanioideae are of great importance but still scarce. Here, the anatomy of roots, rhizomes and scapes of five Amazonian species of Mapania is studied. The species have two types of roots, which differ anatomically: thick roots, serving mainly for fixing, and thin ones, mainly for nutrient absorption. Rhizomes show a uniform anatomical pattern, with amyloplasts and phenolic idioblasts in the cortex and in the vascular cylinder, without aerenchyma. In this organ, the collateral vascular bundles are similar to those found in Hypolytrum, a genus closely related to Mapania within Mapanioideae, suggesting that this feature may be diagnostic for the tribe Hypolytreae. The scape anatomy of the species is taxonomically important at species level but does not corroborate precisely the infrageneric classification of the genus. Finally, the aerenchyma found in roots and scapes is an adaptive character state for a humid forest environment. This work contributes valuable information for the anatomical characterization of vegetative organs of Mapania and discusses its taxonomic and ecological relevance.  相似文献   

11.
    
Bymeans of HPLC technique, the theanine and gallic acid in the leaves of six species and three varieties of Camellia sect. Thea were analyzed. The results showed that both of them were generally occured in these plants and the contents in C. taliensis and C. kwangsiensis are mostly close to those of C. sinensis var. assamica. Since the leaves of C. taliensis have also been historically used for preparing tea by folk peoples of Yunnan province, it could be suggest that C. taliensis might one of the original plants of tea  相似文献   

12.
The Pliocene Eastern Mediterranean fish record is revealed through the study of a 60-m thick stratigraphic sequence near the village Voutes (Heraklion, Crete). Forty-two species belonging to twenty families are identified. Calcareous nannoplankton biostratigraphy places the studied sequence within the biozone MNN16a (latest Zanclean). The stratigraphic distribution of 31 species is modified. Among these, 12 species are reported for the first time in the Eastern Mediterranean Zanclean, while 19 species are first reported outside the Ionian Sea. The Voutes fish fauna presents a diversified benthic and benthopelagic assemblage filling a significant gap in the fossil record.  相似文献   

13.
Plagiochila dubia Lindenb. & Gottsche is reduced to a synonym of the Neotropical P. patula (Sw.) Lindenb. Specimens from the Canary Islands and Madeira proved to belong to the eastern North American P. virginica A.Evans, new to Europe. Phylogenetic analyses of the internal transcribed spacer regions (ITS1-5.8S-ITS2) of nuclear ribosomal DNA of ten Plagiochila species produced four independent lineages that are well supported by all bootstrap analyses (maximum likelihood, maximum parsimony, and distance). These lineages correspond with the Plagiochila sections Arrectae, Contiguae, Cucullatae and Glaucescentes. Spruce's “Ramiflorae” and “Cauliflorae” may no longer be regarded as monophyletic units of Plagiochila. Received August 19, 2001 Accepted October 11, 2001  相似文献   

14.
    
A new species, Arubis beirunu P. Silveira, Paiva & N. Marcos, from central Portugal is described and illustrated. A list of diagnostic differences between Arabis beirana and the closely related species A. sadina and A. stenocarpa is provided  相似文献   

15.
报春花属 (PrimulaL .)藏报春组 (sect.AuganthusPaxexBalf.f.)和毛茛叶报春组 (sect.RanunculoidesChenetC .M .Hu)的界定一直是没有解决的问题。应用核糖体DNAITS序列数据探讨其系统发育关系。取样包括藏报春组和毛茛叶报春组的全部 5个种以及其他一些相关组的代表种。ITS系统树表明 ,陕西羽叶报春 (P .filchneraeKnuth)应与藏报春 (P .sinensisSabineexLindl.)和野藏报春 (P .rupestrisBalf.f.etFarrer)一起置于藏报春组 ;毛茛叶报春组只含两种 :毛茛叶报春 (P .cicutariifoliaPax)和安徽羽叶报春 (P .merrillianaSchltr.)。这两组并不具密切亲缘关系 ,它们在报春花属中与其他组的关系还需进一步研究。研究也表明ITS序列可以为报春花属的系统发育重建提供大量可靠资料  相似文献   

16.
The Neogene Siwalik deposits of Jammu Province (India) have yielded amphibians and squamates. The collection includes the first amphibians and the first colubroid snakes from the Siwalik Group. Amphibians comprise only anurans: a possible Ranidae and one, or perhaps two, non-ranid frogs Squamates include one lizard,Varanus sp. (Varanidae), whereas snakes are represented by three taxa:Acrochordus dehmi (Acrochordidae), an indeterminate Colubridae, and a snake that is either a Colubridae or an Elapidae.Varanus sp. andA. dehmi have been yielded by the Upper Miocene Ramnagar Member, whereas the anurans and colubroid snakes come from the Upper Pliocene Labli Member. These taxa are indicative of aquatic palaeoenvironment.  相似文献   

17.
    
《Palaeoworld》2022,31(1):153-168
Albizia, a diverse tree genus, occupies monsoonal warm humid rain forests in tropical and subtropical regions. We recovered a well-preserved compound fossil leaf and two fossil fruits of Albizia (Fabaceae) from the latest Neogene (Rajdanda Formation: Pliocene) sediments of Jharkhand of the Chotanagpur Plateau, eastern India. On the basis of the architectural features of the fossil leaf, a new species is established as A. mahuadanrensis Hazra, Hazra and Khan, n. sp., characterised by a bipinnate, compound leaf having a rachis bearing opposite, asymmetrically ovate to sub-rhomboid leaflets, pulvinus on leaflet petiolule and brochiodromous secondary veins. Based on both morphological and anatomical characters of the fossil fruits, A. palaeoprocera Hazra, Hazra and Khan, n. sp. is erected, characterised by flattened to broadly linear shaped, wingless fruits; ovate-elliptic shaped seed chambers having ellipsoidal seeds in one series; irregularly polygonal to rectangular epidermal cells with oblique end walls and randomly oriented, scattered, paracytic stomata. Analysis of Albizia fossil occurrences indicates that the legume taxon was common in Neogene forests of India and elsewhere. The present-day distribution of the closely affiliated modern species of the fossil taxa indicates a warm and humid tropical environment during the time of deposition. We also review the biogeographic history of Albizia in India and other Asian countries.  相似文献   

18.
十字花科一新属——泡果荠属   总被引:9,自引:2,他引:9  
岩荠属泡果荠组植物(Cochlearia L.Sect.Hilliella O.E.Schulz)不仅在体态上而且在其它一系列特征特别是具泡状突起的果实特征上极不同于狭义的岩荠属(Cohc-learia L.s.str.),松蓝叶岩荠属[Glaucocochlearia(O.E.Schulz)Pobed.],以及拟常绿岩荠属[Pseudosempervium(Boiss)Grossh.]。这些特征看来可以作为建立一新属的根据,因此将其提升为一独立的属并把这一组的8个种组合到新属中去。  相似文献   

19.
    
A new species of Centaurea L., C. kizildaghensis (Cardueae: Asteraceae), is described and illustrated from south Anatolia. It is restricted to the serpentine rocky slopes of Kızıl Dağ (C3 Konya–Derebucak, Çamlık), and is closely related to C. pseudokotschyi Wagenitz and C. drabifolioides Hub.-Mor., from which it differs in stem, leaf, and phyllary appendage characters. The diagnostic morphological characters are discussed. A new key is produced for Group G species for the flora of Turkey.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 61–66.  相似文献   

20.
The present study deals with the effect of migration on the adult body dimensions among the Oraons of Estern India. The study was conducted on the 232 sedente Oraon of both sexes from Gumla district, Bihar, India and their 230 migrant counter-parts of both sexes from the tea gardens in Duars are, Jalpaiguri district, West Bengal, India. The results show that the migrants are lighter and slightly shorter.  相似文献   

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