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1.
《Palaeoworld》2021,30(4):689-707
The Bashkirian (Late Carboniferous) ammonoid genus Bilinguites has a nearly global distribution in the tropical and subtropical zones and 25 species have been described up till now. Most of them are considered endemic, but some may have a wide geographic distribution. Our study on new and previously collected materials from North China (Gansu and Ningxia) shows that the stratigraphically youngest species of Bilinguites in North China and Western Europe are morphologically very similar, possibly indicating correspondence of the ammonoid faunas. Bilinguites scalpratus is revised and established as a stratigraphically important species of the genus in North China; it co-occurs with the first gastrioceratid species Cancelloceras pachygyrum. This occurrence can be correlated with the Western European co-occurrence of Cancelloceras cancellatum and Bilinguites superbilinguis at the base of the G1 Zone.  相似文献   

2.
New outcrops discovered in detrital ante-Stephanian sequences of the Southwestern Pyrenean Axial Zone (Béarn and Basque Country), yield abundant and varied faunas and floras. Among these the goniatite faunas are of particular interest. In a detailed palaeontological study, 9 species of Namurian age are recognized characterizing 3 levels of different age: the levels R1a2 (Reticuloceras circumplicatile Subzone) and R1a3 (Reticuloceras todmordenense Subzone) belong in the lower R1 Zone (Kinderscoutian, Reticuliceras inconstants Zone), Namurian B; the third level is Upper Namurian in age (Yeadonian, lower Gastrioceras Zone), Namurian C. These goniatite associations are palaeogeographically linked with those of the rest of Europe and North Africa, but their stratigraphical succession is not continuous.  相似文献   

3.
4.
Presimoceras is a new genus of Idoceratinae. The biostratigraphical range ofPresimoceras is limited to theStrombecki, Divisum and lower part of theAcanthicum Zone within the Kimmeridgian (in the Southern European sense). The genusMesosimoceras (Idoceratinae) was instituted by Spath (1925), withSimoceras cavouri Gemmellaro as type species; this genus is here emended with the institution ofPresimoceras n. gen. The species groupcavouri-risgoviense is preserved in the emended genusMesosimoceras, while the groupherbichiludovicii-teres is accommodated inPresimoceras on account of the radical and numerous differences and the stratigraphical gap betweenMesosimoceras andPresimoceras. As type species of the new genusAmmonites nodulatus Quenstedt is designated. The new genus is here subdivided into three groups of species:herbichi, ludovicii andteres. Phylogenetically,Presimoceras is derived fromPassendorferia, Mesosimoceras fromNebrodites.  相似文献   

5.
A partial skull from the upper Muschelkalk (mo3,praenodosus to lowernodosus Zone) of Wasselonne (Alsace, France) is described and identified as third specimen ofCyamodus kuhnschnyderi. The dentition of all species currently included in the genusCyamodus is discussed, and instances of individual variation are identified. In contrast to the type material, the new specimen ofCyamodus kuhnschnyderi has two pairs of premaxillary teeth, and thus adds incongruence to the stratophenetic trend of dental reduction previously identified within the genusCyamodus.  相似文献   

6.
Biometrical investigations on coccoliths of the genusGephyrocapsa from the Neogene of the North-Atlantic were carried out using scanning-electron micrographs and yielded the following results: The different species ofGephyrocapsa are best distinguished from one another using the following morphological features coccolith-size, bridge-angle, roundness, and pore-width because these characteristics are not intercorrelated and can be easily measured. Tracing the development of these characteristics allows the reconstruction of the evolution ofGephyrocapsa in Pliocene and Quaternary periods and leads to a revision of this genus. Earliest forms ofGephyrocapsa are found in theReticulofenestra pseudoumbilica Zone (NN 15) of the Early Pliocene. In the Late Pliocene three different evolutionary lines, i. e. groups of species, can be distinguished and subsequently followed until present time. At the base of the Pleistocene a fourth line branches off which evolves throughG. caribbeanica toG. oceanica and is significant for the nannoplankton zonation of the Quaternary. Based on these biometrical investigations 11 species can be distinguished within the genusGephyrocapsa which only in part are identical with previous named species. Three new species had to be added.  相似文献   

7.
The morphology and the anatomy of the 13 species presently included in the genusFulgensiawere surveyed.Caloplaca aureaandC. paulii, two species regarded as closely related toFulgensiaby earlier authors, were also included in the study.Fulgensiawas found to exhibit a great variation in both morphology and anatomy. The differences in size, shape and septation of the spores, in the anatomy of cortex and exciple, and in the gross morphology, will presumably motivate a different taxonomic treatment in the future. A tentative separation of the species into four different groups is proposed here. Group A comprisesF. australisandF. chanousiae, which appear close to species inCaloplacasect.Gasparrinia.Groups B and C, each comprises one species,F. schistidiiandF. canariensisrespectively and group D comprises the remaining nine species, including the type speciesF. fulgens. The last group may be further split by a more detailed investigation. The present separation ofFulgensiainto two subgenera cannot be regarded as taxonomically sound. The genus is probably polyphyletic and the different groups are probably related to different groups within the large genusCaloplaca.  相似文献   

8.
A. Spencer Tomb 《Brittonia》1972,24(2):223-228
Prenanthella is re-established as a genus distinct fromLygodesmia on the basis of morphological, palynological, and chromosomal data. Possible relationships ofPrenanthella to other Stephanomerinae and to the genusCrepis are suggested.  相似文献   

9.
A new genus,Siemensichthys, from the Upper Jurassic of southern Germany is described. The new genus includes two species,S. macrocephalus (Agassiz) which was formerly in the genusPholidophorus, andS. siemensi n. sp. The two species share synapomorphies such as only one supramaxillary bone covering the dorsal margin of the maxilla. Both species are described, and their phylogenetic position is analyzed. The phylogenetic analyses, based on 27 taxa and 141 characters, show thatAnkylophorus from the Kimmeridgian of Cerin,Siemensichthys andEurycormus from the Solnhofen Lithographic Limestone of Bavaria, form a monophyletic group. The new extinct clade (preliminarily identified as theSiemensichthys- group) is proposed as the sister-group ofPholidophorus s. str. plus more advanced teleosts. This sister-group relationship is supported by eight characters (e.g., supraoccipital bone extending forward in the roof of the otic region; articular bone fused with both the angular and retroarticular; presence of an elongated posteroventral process of quadrate; presence of dorsal processes at the base of the innermost caudal rays of upper lobe; mobile premaxillary bone). Comparisons with species ofPholidophorus s. str. provide a new understanding of the genusPholidophorus. At least four synapomorphies are proposed to support the monophyly ofPholidophorus. As a consequence of this new interpretation, the European Late Jurassic species previously assigned to the Pholidophoridae and to the genusPholidophorus (e.g., ‘Ph.’armatus, ‘Ph.’ falcifer, ‘Ph.’ micronyx, ‘Ph.’ microps) should be reexamined because they do not belong to the family nor to the genus. The order PholidophoriformesBerg is not a monophyletic group as currently constructed. Therefore, all so-called pholidophoriforms are in need of revision.  相似文献   

10.
Recent records ofVascoceras andNigericeras from the Cenomanian are reviewed and considered to be based upon mis-identification and/or questionable stratigraphic evidence. Phylogenetic relationships suggest that both these genera are wholly Turonian. The new genusProvascoceras is erected for the uppermost CenomanianVascoceras diartianus (d’Oreigny) whilst the Upper CenomanianPseudotissotia inopinata Kennedy & Bayliss is shown to be an homoeomorphous offshoot ofAcompsoceras, unrelated to the Turonian genus, for which the new genusKennediella is proposed. A refined zonal subdivision of the Turonian Stage is proposed.  相似文献   

11.
The development of the genus concept for platform-bearing gondolellid conodonts is discussed. The collective genusNeogondolella Bender & Stoppel s. l. must be subdivided into several genera separated mostly by morphological differences of their platform elements. Only for these genera, but not forNeogondolella s. l., differential diagnoses againstGondolella Stauffer & Plummer s. l. can be given.Norigondolella n. gen., species of which were formerly placed intoParagondolella Mosher s. l.,Gondolella Stauffer & Plummer s. l. orNeogondolella Bender & Stoppel s. l., is a typical gondolellid platform conodont genus of topmost Triassic (Norian-Rhaetian) pelagic sediments. It has evolved from Carnian representatives ofParagondolella, but the lower surface of the platform element shows considerable similarities (homoeomorphy) to the Middle Carboniferous to Middle Permian genusMesogondolella Kozur.  相似文献   

12.
Peter Goldblatt 《Brittonia》1975,27(4):373-385
The native bulbous Iridaceae of North America excluding Mexico comprise seven species in four genera. The type species ofAlophia Herb. (1836) is shown to belong toEustylis Engelm. & Gray (1836), hence the latter genus is reduced to synonymy. The well known genusAlophia (sensu auct. non Herb.) (Herbertia Sweet) now takes the nameTrifurcia. As a result of the new interpretation ofAlophia, new combinations are made for the North American and Latin American species ofTrifurcia andAlophia. New chromosome counts are given forNemastylis floridana (2n = 56) andTrifurcia lahue (2n = 56).  相似文献   

13.
The basal plate of the genusPorochara MäDLER 1955 (Porocharaceae, Charophyta) was proved to be divided into two parts by examining its type species. ThusMusacchiella Feist & Grambast-Fessard 1984 is a younger synonym ofPorochara. The genusFeistiella n. gen. is established for those species with undivided basal plates and it is described with the type speciesFeistiella bijuescensis n. sp. Six other species are attributed to this new genus. The relation between a fan shaped internal structure of the spiral cells and a brackish environment is discussed.  相似文献   

14.
The fossil Carboniferous flora of various localitiesof the «zone primaire axiale in Pyrénées Mountains, which was mainly known only by lists of determinations, is described and figured for the first time, due to the recent discovery of a very nice fossiliferous locality. The plant association comprises Lepidophyta, Arthrophyta, Filicophyta, Pteridospermaphyta and Cordaitophyta, with the following dominant species: Neuralethopteris schelehanii (Stur), Karinopteris acuta (Brongniart), Eusphenopteris hollandica (Gothan & Jongmans), Paripteris gigantea (Sternberg), Calamites cf. cistiiformis (Stur) and Corynepteris sp.Such an association is typical for an Upper Namurian B-Lower Namurian C age in Western Europe. The biostratigraphic results are compared with the data obtained by Goniatites found also in these localities.The identity of such plant-assemblages from WesternEurope as well as South and North-East China is in favour of a continental continuity between these provinces during the Namurian.  相似文献   

15.
The typical series of the genusBilinia ObrhelovA 1971 (Pisces, Percoidei) from the diato-mite beds of Ku?lín near Bílina (North of Bohemia, ?SR) kept in the National Museum of Prag was re-examinated. Morphological comparisons with other Eocene percoid fishes were supplemented with several very important features. As far as necessary, other observations were corrected. Deviations of certain morphological details, which sometimes are noticed among different specimens ofBilinia, are discussed with respect to the probable range of intrageneric variability. A new, revised diagnosis is proposed for the genusBilinia Obrhelová. Concerning the systematics, an assignment of this genus to the Percichthyidae in their widest meaning (c. t. Gosline 1966, Johnson 1984) seems to make more sense than the former classification with the Serranidae. Within this group, especially the genusAmphiperca Weitzel 1933 must be regarded as the presumably closest relative ofBilinia Obrhelová.  相似文献   

16.
Stuessya, a new genus from the Pacific slopes of southcentral Mexico is described. It is comprised of three species:S. apiculata, previously assigned to the genusViguiera;S. perennans, the generotype; andS. michoacana. The latter two taxa are previously undescribed. The genus is characterized by its urceolate, sclerified (at maturity) involucre. Chromosome counts of2n = 34 are reported forS. perennans. Relationships are problematical, but are reckoned to be somewhere betweenAldama andViguiera.  相似文献   

17.
Forty-four chromosome counts from the North American genusCallirhoe are reported, including first-recorded counts ofC. alcaeoides, C. digitata, C. bushii, C. triangulata, andC. involucrata var.tenuissima. Information concerning chromosome numbers from present and previous reports is summarized and evaluated. Observations are presented on meiosis for the genus in general, for male sterile individuals of gynodioecious species, and for selected F1 hybrids. Pollen fertility data are recorded for the latter. Chromosomally three species groups are recognized: an exinvolucellate, diploid species group withn=14; an involucellate, tetraploid and octoploid species pair,n=28 and 56; and an involucellate, diploid and tetraploid species group withn=15 and 30. Intrageneric relationships and those within the tribe Malveae subtribe Malvinae are discussed.  相似文献   

18.
Summary The luminescent bacteria are logically placed in two genera. The common coccoid and frequently non-motile species placed byBeije-rinck first in his genusPhotobacterium, 1889 under the namePhotobacterium phosphorescens syn.Bacterium phosphorescens Fischer, should be recognized as the type species ofPhotobacterium. Other characters indicate that this genus should be placed in the FamilyPseudomonadaceae Winslowet al.. and should include other straight, rod-shaped, luminescent, polar flagellate bacteria that ferment glucose without, however, necessarily producing gas (H2 and CO2) as does the type species. The species that have the form of vibrios should be accepted as members of the genusVibrio as suggested by several previous investigators. They have characters much like those ofVibrio comma, the type species of the genusVibrio.  相似文献   

19.
Fungi of 19 genera, 30 species, and one variety were isolated from 25 samples of sheep-, cattle- and camel feedstuffs collected from different farms in the Beida Governorate, Libya.Aspergillus, Penicillium andFusarium were the most common genera in the three substrates tested. TLC was used to establish the identity of aflatoxins in the chloroform extract of all samples and the ability to produce aflatoxins byAspergillus flavus in a synthetic liquid medium. Twenty samples out of 25 tested were naturally contaminated and 21 isolates ofA. flavus out of 30 produced at least one of the following aflatoxins: B1; B1, G1; and B1, B2, G1, G2. This is the first report about the natural occurrence of aflatoxins and aflatoxin-producers of the genusAspergillus in Libya.  相似文献   

20.
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