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1.
Lithospermum (Boraginaceae) belongs to a small group of plant taxa that accumulate biogenic carbonate in their fruits. In this genus, carbonate incrustations form in the cells of the epidermis and sclerenchyma of the pericarp. Fossil Lithospermum fruits (nutlets) with well-preserved calcified tissues commonly occur in Quaternary sediments and cultural layers. We tested the suitability of biogenic carbonate of Lithospermum fruits for radiocarbon dating using a total of 15 AMS measurement results from four modern and 11 fossil samples. The 14C data from modern samples suggest that Lithospermum utilises only atmospheric carbon to synthesise calcite in the nutlets. In general, the ages determined through 14C dating of fossil fruitscorresponded well with the absolute-age intervals for archaeological sites over the last 5000 yr. Biogenic carbonate of Lithospermum fruits, like that of Celtis, represents a new source of chronological information for late Quaternary studies.  相似文献   

2.
The history of investigation of the common Jurassic and Cretaceous genus Pseudotorellia Florin (Ginkgoales) represented by needle-shaped, narrow linear or lanceolate leaves bearing several veins and characterized by a single type of epidermis, is considered. An extended diagnosis of the genus and its taxonomic composition with regard to the epidermal characters are reported; the stratigraphic and geographical range of its species and the genus evolution are refined. Three new species Pseudotorellia asiatica N. Nosova et Kiritchkova, sp. nov., P. ketoviana N. Nosova et Kiritchkova, sp. nov., and P. samylinae N. Nosova et Kiritchkova, sp. nov. described from the Lower Jurassic (Toarcian) sediments, are proposed as the correlative taxa within the Caspian oil and gas province. The stratotype and reference sections of the Lower Jurassic sediments in the Mangyshlak Mountains are reported for the first time.  相似文献   

3.
The Bathonian sediments of the Jaisalmer Basin, India host a terebratulide brachiopod Plectoidothyris which has been previously known from the Bajocian rocks of the Boreal Province. The sharp and prominent plication of the anterior commissure and increased length of costae separates the Jaisalmer specimens from other known species of the genus and the population represents an endemic species — Plectoidothyris jaisalmerensis. The population was only cursorily described earlier lacking in details of precise stratigraphic control and was wrongly assigned to a different genus. The present study is based on a large number of specimens from different localities with precise stratigraphic data, coupled with this some recent findings of time-diagnostic ammonites have helped determine the Plectoidothyris jaisalmerensis duration in the Jaisalmer Basin as the Late Bathonian. Presence of lower Jurassic Boreal brachiopod genera in the Middle Jurassic rocks of Ethiopian and Indo — Madagascan biogeographic provinces has been noticed earlier whereto Plectoidothyris is a new addition while it is also the first report of the genus from the Jurassic of India. The brachiopod migrations from the north to south of the Tethys provide evidences for opening of shallow water routes in the Tethyan seaway and are probably indicative of warmer water conditions in the Indo-Madagascan and African areas during the Middle Jurassic.  相似文献   

4.
A new genus, Cretaproscolia, and three new species of scoliid wasps, Archaeoscolia hispanica, Cretoscolia montsecana and Cretaproscolia josai, are described from the Lower Cretaceous of Spain and Brazil. The species representing the new genus is attributed to the plesiomorphic extant subfamily Proscoliinae, while the two other new species are assigned to two previously described genera in the extinct, archaic subfamily Archaeoscoliinae. The Brazilian species is the first Mesozoic scoliidid to have been described from the New World.  相似文献   

5.
The extant genus Paliurus Miller is divided into P. ramosissimus and P. spina-christi groups and is diagnostically characterized by distinctive orbicular-winged fruits with a trilocular (or often bilocular) ovary and basally triveined leaves with a subentire to serrate margin. Here, structurally preserved winged fruits and associated compressed leaves of Paliurus (Paliureae, Rhamnaceae) are reported from the Middle-Upper Miocene Shengxian Formation of Tiantai, Zhejiang, eastern China. The fruits can be identified as Paliurus microcarpa Xiang-Chuan Lisp. nov., the diagnostic characters of external morphology and anatomy of which differ from those of both extant and fossil generic members; the leaves can be designated as Paliurus sp. The species based on winged fruits, P. microcarpa, might represent an ancient intermediate link exclusively known across the P. ramosissimus and P. spina-christi groups, showing a closer affinity to the P. ramosissimus group based on the resemblant smaller fruits with a narrower wing, and to the P. spina-christi group based on the similar wing structure and texture, respectively. Morphological analyses of the present and previous fossil fruit records around the world indicate that diversification of Paliurus had begun in northern transpacific regions by the Late Eocene. The macrofossil records, i.e., fruits and leaves of Paliurus globally when projected on paleoenvironmental maps in view of changing continental positions through time (from Eocene to Miocene) display that the past distribution of the genus was much wider than the present and belongs to a tropical and warm temperate realm of the Northern Hemisphere. Therefore, the modern restricted disjunction in tropical and warm temperate regions of East Asia and South Europe (even eastwards West Asia) might represent glacial refugia for some of the generic ancient lineages to survive severe cold at least since the terminal Pliocene.  相似文献   

6.
中国南方泥盆系发现颗石藻   总被引:1,自引:0,他引:1       下载免费PDF全文
颗石藻作为一种超微远洋浮游生物,出现于侏罗纪里阿斯世(Lias),繁盛于晚白垩世至第三纪。最近又有所进展。哈克(Hag,1981)面告,最老的颗石藻出现于石炭纪和二叠纪。本文所报道之颗石藻发现于晚泥盆世,是截至目前为止最老的颗石藻化石。 颗石藻演化迅速,分布广泛,形态特征明显,而且数量众多,对划分对比海相地层有一定的意义。本文只对研究区所采标本的颗石藻进行鉴定、描述和分类。  相似文献   

7.
The analysis of paleontological remains in many samples from the Lower Quaternary Chauda sediments drilled and cored on the Bulgarian shelf of the Black Sea revealed widespread mollusks of the genera Didacna and Dreissena (Didacna tschaudae guriana, D. tschaudae, D. pleistopleura, D. crassa guriensis, Dreissena rostriformis tschaudae, D. rostriformis abchasica) accompanied by reworked Neogene representatives of the genus Digressodacna. In numerous places of a continental slope and an adjacent deep-sea depressions near Crimea and Caucasus the similar mollusc assemblage is described in the redeposited state for the first time. The composition of palynological spectra and diatom assemblages in shelf sediments indicates climate changes during the Chaudan period. The Chaudan mollusk fauna from the Black Sea sediments, which is lacking Caspian Bakuan species characteristic of the Chauda stratotype, is compositionally close to the mollusk assemblage from basal layers of the Chauda Horizon in the Guriya area of Georgia (“Gurian” Chauda). These data imply repeated changes in the level of the Chaudan basin between present-day isobaths of −30...−50 to −140 m.  相似文献   

8.
Three new species within the stigmaphronid genus TagsmiphronEngel and Grimaldi, 2009, and one new species within the megaspilid genus ConostigmusDahlbom, 1858 are described from Upper Cretaceous (Campanian) amber originating at the Grassy Lake locality in Alberta, Canada. New taxa include Tagsmiphron spiculum sp. nov., Tagsmiphron leucki sp. nov., Tagsmiphron exitorum sp. nov., and Conostigmus cavannus sp. nov. The new Conostigmus species is a rare discovery. It is the third megaspilid species to be found in Cretaceous amber, with the two specimens described herein effectively doubling the number of known Mesozoic exemplars for the family. We provide the first comprehensive report of known Ceraphronoidea within Canadian amber, and contrast this against other Cretaceous amber assemblages, discussing the potential palaeobiogeographic and palaeoenvironmental implications of the Canadian amber assemblage.  相似文献   

9.
Inflorescences of Mauldinia (Lauraceae) are described from the middle Cenomanian Pauletian facies of Gard, Languedoc-Roussillon, south-eastern France. This is the first record of the genus from this part of Europe. Mauldinia sp. is described based on peduncles and lateral units. Isolated, slender peduncles show spirally arranged scars or rarely attached lateral units. Isolated lateral units consist of cladode-like structures showing up to seven flower/fruit scars. Some isolated fruits were found associated with peduncles and lateral units. Fruits are ovoid fruits contain a single, elongated seed. The pericarp consists of epicarp, mesocarp and endocarp. The seed consists of two cotyledons containing well-developed reserve cells. Mauldinia sp. from Gard differs from known Mauldinia species by having longer internodes along the peduncle and by the shape of the lateral units. Sedimentological and palaeontological evidence suggests that Mauldinia sp. from Gard grew in a protected, littoral environment with limited marine influence. This report provides new information to the relatively poorly known Cretaceous record of angiosperms in France. The occurrence of Mauldinia in the lower Upper Cretaceous of Gard corroborates the widespread occurrence of the genus in marginal littoral environments during the mid-Cretaceous.  相似文献   

10.
A new species of wasp from the Laiyang Formation in Shandong, China is described and named Cretaproscolia asiatica sp. nov. It is the second record of the genus Cretaproscolia Rasnitsyn and Martínez-Delclòs, 1999, and extends the distribution of the genus from the Lower Cretaceous of South America into the upper Mesozoic of East Asia. The diagnosis of Cretaproscolia is emended based on the new material.  相似文献   

11.
A new fossil leaf impression is described from the Early Miocene sediments of Kasauli–Kalka road section, Himachal Pradesh. The characteristic leaf venation pattern suggests that it has a close affinity with Ficus L., particularly with F. racemosa L. (= F. glomerata Roxb.). Its presence indicates a warm and humid climate in the region during the deposition of sediments, in contrast to the present day cooler and less humid climate.  相似文献   

12.
Pterospermumocarpon (Type: P. kalviwadiensis), a new morphogenus of fossil fruits showing resemblance with fruits of extant Pterospermum Schreb. (Malvaceae s.l.), is described from the Sindhudurg Formation (Miocene) at the Kalviwadi Village, Sindhudurg District, Maharashtra, India. Diagnostic feature of the fossil taxon is the dehiscent pentalocular capsule with five distinct sutures and imprints of winged seed-like structures in the locules. Recent modifications in the systematics of the Malvales, their fossil record, and the distribution and migration of Pterospermum and other malvalean taxa in the context of the Indian subcontinent are discussed.  相似文献   

13.
The occurrence of the genus Aquilapollenites in Upper Cretaceous and Neogene sediments of northwestern Pakistan is reported here. Aquilapollenites amplus, Aquilapollenites reductus, and Aquilapollenites sp. occur in the Maastrichtian palynomorph assemblage from an outcrop sample of the Mir Ali section, northern Waziristan. Aquilapollenites medeis in the Neogene Murgha Faqir Zai Formation of the Pishin Basin, Balochistan, is considered a reworked Cretaceous specimen. The Upper Cretaceous sediments of the Asian plate on the Tethys margin are considered to be the source of Aquilapollenites spp. in these samples.  相似文献   

14.
TORE P°SSE 《Sedimentology》1997,44(6):1011-1014
The grain size distribution within a unimodal sediment can be described as a lognormal distribution when the distribution is formed by only one process. However, most sediments are formed by more than one process giving polymodal sediments. Polymodal sediments have to be described as the sum of several normal distributions, one for each process involved within the formation. Grain size distributions are usually interpreted with the help of graphical methods. Interpretations of polymodal sediments require mathematical methods. In mathematical terms a unimodal sediment can be described as a tangential hyperbolic function (tanh) and a polymodal sediment can generally be described by the sum of two or three tanh-functions. The tanh-method is a tool for identifying and estimating the number of modes within a grain size distribution and helps interpret the processes involved within the formation of a deposit. The mathematical method can also be used to computerize sediment data, allowing storage with just a few numbers. Different samples can easily be compared and classified. Also, this method could be a valuable tool for calculations of various sediment parameters both in geotechnology and hydrogeology.  相似文献   

15.
<正>A new fossil chironomid,Tanytarsus serafini,found in Baltic amber is described and illustrated based on adult males.The new species and similar extant species of the genus Tanytarsus van der Wulp are compared. Due to several distinct characters of wing,legs and hypopygium,a new species group for Tanytarsus serafini is proposed,and its diagnostic features are evaluated.  相似文献   

16.
This paper reports the first fossil (Tertiary) occurrence of freshwater sponges of the genus Ephydatia in the southern hemisphere. The sponges appear in diatomite lacustrine sediments of Late Miocene Quillagua Formation (Chile, Atacama region). The investigated specimens represent a new species, Ephydatia chileana sp. nov., which is close to the Recent cosmopolitan E. fluviatilis. On the basis of sedimentological and diatom assemblage data, sponge-bearing diatomites have been interpreted as deposited in open offshore shallow lacustrine conditions with slightly alkaline waters. The sponges show malformations, similar to some diatoms and probably caused by high heavy metal concentrations in a lake water. These concentrations are related to hydrothermal activity, which favored the leaching of volcanic rocks that outcrop extensively in the catchment.  相似文献   

17.
In this paper one new genus and three new species Bellimordella capitulifera gen. et sp. nov., B. longispina gen. et sp. nov., B. robusta gen. et sp. nov., all placed within the subfamily Praemordellinae of the family Mordellidae, are described and illustrated. The specimens were recovered from the Yixian Formation of Beipiao City, Liaoning Province, NE China. The key to the species of this new genus is given. Furthermore, we discuss evolution of the pygidium and possible food for those ancient mordellids.  相似文献   

18.
The Kocali Complex in SE Turkey includes pelagic sediments (pelagic limestones, cherts, etc.), basic volcanic rocks of oceanic crust origin together with platform-derived sediments. Its depositional age was previously assigned as Late Jurassic–Early Cretaceous. In order to study the radiolarian contents of volcano-sedimentary sequences in this complex, six stratigraphic sections have been measured mainly at the NE and NW Adiyaman city.Radiolarian faunas from these stratigraphic sections reveal that the age of these sequences ranges from middle Carnian to Rhaetian. Based on these data, the depositional age of the complex is older than the previously assigned. Lithological characteristics (widespread Triassic basic volcanic rocks associated with pelagic sediments) and radiolarian contents of these sequences have close similarities with the sequences of the Alakircay Nappe of the Antalya Nappes in western and central Taurides.Based on taxonomic studies, 99 taxa have been determined of which one genus (Adiyamanium) and four species (Monocapnuchosphaera kocaliensis, Paronaella speciosa, Ferresium okuyucui and Adiyamanium crassum) are described as new.  相似文献   

19.
<正>A new genus and species of Rhachiberothidae,Raptorapax terribilissima gen.et sp.nov.from the Cretaceous amber of Lebanon is described.The new genus is assigned to the subfamily Paraberothinae.The new material confirms the great diversity of the group in the Cretaceous age and its decrease in diversity in recent times.  相似文献   

20.
Three new species, Lebanoculicoides excantabris, Archiaustroconops borkenti, and Atriculicoides szadziewskii are described from the Early Cretaceous (early Albian) El Soplao amber deposit (Rábago, Cantabria, northern Spain). Protoculicoides skalskii Szadziewski and Arillo, found in the other Albian Spanish ambers from Peñacerrada I (in Burgos) and San Just (in Teruel), and Austroconops sp., are identified from this new outcrop. The find of a new species of Lebanoculicoides Szadziewski is especially significant since this genus is considered the basalmost known among ceratopogonids. To date, the new species of Atriculicoides Remm is the oldest occurrence for this genus. A general review of the taxonomy and phylogeny of the family Ceratopogonidae, and the palaeoecological significance and palaeogeographic distribution of its basalmost lineages are given. The new data extend knowledge about biting midges during the Early Cretaceous, a key period for understanding the phylogenetic relationships of the ancient members of the family.  相似文献   

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