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Two fertile ferns from the Stephanian of the Massif Central (France) are described in detail. One has been found in the Blanzy basin and is assigned to Oligocarpia (Sphenopteris) leptophylla (Bunbury) nov. comb., according to the morphology of the sterile pinnae and of the fructifications. Its spores agree with the «sporae dispersae Granulatisporites parvus (Ibr.) Potonié and Kremp. The other fern has been collected in the St Etienne basin and is assigned to Senftenbergia plumosa (Artis) Radforth var. ligerensis nov. var. Its spores agree with the morphographic genus Raistrickia (S., W. and B.) Potonié and Kremp but do not look like any described species; therefore the new species name R. polymorpha nov. sp. has been given to that spore.  相似文献   

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Abstract:  The Carnian (Late Triassic) flora of Lunz in Lower Austria is famous for an abundance of well-preserved bennettitalean and cycadalean foliage and reproductive structures. However, only the fertile remains have been studied in detail to date. Recently completed systematic macromorphological and cuticular analyses of leaf fossils from Lunz revealed that several forms previously accommodated in the genus Macrotaeniopteris do not represent ferns but rather Bennettitales assignable to the genus Nilssoniopteris . We describe three species of Nilssoniopteris , which represent the first records for this genus from Lunz, and one of the earliest accounts of Nilssoniopteris in the Northern Hemisphere. The following new combinations are introduced: Nilssoniopteris haidingeri (Stur ex Krasser, 1909 a ) comb. nov., N. angustior (Stur ex Krasser, 1909 a ) comb. nov. and N. lunzensis (Stur ex Krasser, 1909 a ) comb. nov. The discovery of Nilssoniopteris further substantiates the significance of the Lunz flora as one of the richest and most diverse early Late Triassic floras from the Northern Hemisphere.  相似文献   

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The first occurrence of attached fertile structures to foliage assignable to the form genus Triphyllopteris Schimper is reported from the early Carboniferous Price Formation of southwestern Virginia. Sporangium-bearing branch systems consisting of a basal undivided foliar region and a distal much-divided fertile region are described as a new species T. uberis Skog and Gensel. Ovoid fusiform sporangia, 2.0 mm long and 0.5 mm wide and containing trilete spores, terminate ultimate divisions of the branch systems and collectively form masses up to 4 cm in all dimensions. T. uberis is compared to previously known sporangiate organs of Late Devonian and early Carboniferous age, many of which lack attached foliage. Similarities in the overall branching pattern of many of these non-synangiate, sporangiate organs of early Carboniferous age is noted. The possible mode of dispersal and affinities of the plant bearing T. uberis fertile foliage is discussed.  相似文献   

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This study deals with four form or organ genera from the Upper Mississippian (Chester Series) of the Illinois Basin, and provides evidence that they were produced by a single natural genus with gymnospermous affinity. The plant remains—compressions, impressions, petrifactions, and specimens that combine compression or impression with petrifaction—allow examination of both external morphology and internal anatomy. The specimens include foliage corresponding to Rhodea, stems and petioles corresponding to Heterangium, and synangiate fructifications corresponding to either Telangium or Telangiopsis. The stems and foliage are considered parts of the same plant because of the identity of the anatomical and cuticular features of petioles attached to stem and those petioles with attached foliage. The fertile material is regarded as part of the same plant because: (1) The anatomy of axes of the fertile specimens is like that of the sterile specimens. (2) A single specimen may contain both sterile Rhodea-type axes and fertile regions. (3) Axes bearing synangia have the same size and patterns of divisions as the sterile foliage. Features that indicate lyginopterid affinities include: (1) Equal forking of the petiole. (2) Presence of fiber bands in the outer cortex and sclerotic nests in the inner part of the cortex. (3) Crowded circular bordered pits on the lateral walls of the metaxylem tracheids. (4) The presence of a small amount of secondary xylem. A variety of structural details of the stem and petiole suggest the genus Heterangium. The phyletic position of the plant that produced Rhodea, Telangium, Telangiopsis, and Heterangium is reviewed in light of such discoveries as the presence of a planated frond that lacks a lamina and the presence of both monolete and trilete microspores in a single synangium.  相似文献   

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The genus Pseudorthocladius Goetghebuer, 1943 from China, including 12 species, is reviewed. Five new species, P. (P.) binarius sp. n., P. (P.) cylindratus sp. n., P. (P.) digitus sp. n., P. (P.) ovatus sp. n. and P. (P.) paucus sp. n. are described and illustrated as adult males. P. (P.) cristagus Stur & Sæther, 2004, P. (P.) jintutridecima (Sasa, 1996), P. (P.) macrovirgatus Sæther & Sublette, 1983, P. (P.) morsei Sæther & Sublette, 1983, P. (P.) uniserratus Sæther & Sublette, 1983, P. (L.) wingoi Sæther & Sublette, 1983 are newly recorded in Oriental Region. A key to the males of Pseudorthocladius in China is presented.  相似文献   

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Yves Almeras 《Geobios》1979,12(2):187-221
In the course of researches on the fauna of «calcaires bajociens á bryozoaires of Aveyron départment (France), numerous collects of shells named Rhynchonelloidea ruthenensis (Reynès), type-species of genus RhynchonelloideaBuckman, in two localities enabled to do a morphologic study of this species with populations analysis. Internal characters have been shown both by serial sections and by direct observation of dissected shells. A comparison of genus Rhynchonelloidea and Homoeorhynchia, till now either distinct or considered synonymous according to authors, has been realised. Internal characters of Homoeorhynchia acuta (Sow.) have been precised. The two genus are distinct by beak and foramen's characters, by presence or lack of costulation on the beak and dorsal umbo, by the number of ribs, by presence or lack of septalium and by the development of median dorsal septum.The stratigraphical range of R. ruthenensis is:Upper Toarcian, Aalensis zone-Lower Aalenian, Opalinum zone.  相似文献   

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The fertile glossopterid Senotheca is represented by linear fructifications with broad wings attached to the midribs of Glossopteris leaves. The architecture of the reproductive structures supports their placement within the Dictyopteridiaceae. The genus is emended, the validity of two established species (Senotheca murulidihensis and S. kingii) is confirmed, two new species (Senotheca keiraensis and S. magna) are formally defined and one taxon characterized by an attached leaf with coarse venation is retained under open nomenclature. Senotheca is distributed from northeastern India to eastern Australia and ranges from the (?)Artinskian to Changhsingian but the biostratigraphic utility of the genus is constrained by its rarity. Several other reports of the genus from Antarctica and southeastern Australia remain doubtful.  相似文献   

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This paper shows fossil spores and pollen grains from Cretaceous (Upper Campanian) of Sakhalin, Russia, with scanning electron microscopy. A total of 520 palynomorph assemblages consisting of 25% spores of pteridophytes and bryophytes, 4.5% of ephedroid pollen grains, 6.5% of coniferous pollen grains, and 64% of angiospermous pollen grains were recovered in the present study. 5 genera of pteridophytes, 4 genera of gymnosperms, and 18 genera of angiosperms are described in the present study. The frequent and representative genera from the stratum areEphedripites, Liliacidites, Clavatipollenites, Tricolpites, Aquilapollenites, andAzonia. A new genus,Sciadopitipollenites, that is comparable with extantSciadopitys is proposed in the present study. Polycolpate pollen with the same exine sculpture ofClavatipollenites suggests a generic differentiation in the Chloranthaceae during the Cretaceous age. The diverse spores and pollen paleoflora shown in the present study suggests a wide diversification of angiosperms in the Upper Campanian at the eastern side of Laurasia (Aquilapollenites province).  相似文献   

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A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp. n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined.  相似文献   

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Compressed specimens of the fern Osmunda are described from the Triassic of the Allan Hills, Antarctica. The specimens consist of a once pinnate, deeply pinnatifid fertile frond as well as several sterile specimens. Six pinnae are present on the partial fertile rachis, with two sterile pinnae above four fertile pinnae. Both sterile and fertile specimens are virtually identical to the modern species Osmunda claytoniana. Entire fronds are fragmentary; the longest is 21 cm in length. Sterile pinnae are alternate and deeply pinnatifid, with slightly toothed pinnules and dichotomous venation. Fertile pinnae are 1-1.3 cm long, once pinnate, and lack vegetative lamina. Sporangia are clustered, each 300-375 um in diameter, and possess a transverse annulus 6-8 cells long; dehiscence is by a vertical slit. Fronds arise from a rhizome 4 cm long by 1 cm wide; two croziers are present on the rhizome. Two frond segments up to 6 cm long and three deeply pinnatifid pinnae are present on the uppermost part of one rachis. Pinnules are ~4 mm long and 2-3 mm wide. The presence of this Osmunda species in the Triassic demonstrates stasis of frond morphology, both fertile and vegetative, for the genus.  相似文献   

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Jambadostrobus was established to accommodate fossils consisting of several multiovulate elliptical–ovate fructifications attached to the midline of glossopterid leaves. Two species have been assigned to the genus: J. pretiosus (the type species) and J. hillii from the Late Permian of India and Early Permian of Australia, respectively. Re-investigation of the original specimens reveals that only solitary fructifications are attached to the subtending leaf in J. pretiosus, hence the species is transferred to Plumsteadia, which was founded on equivalent characters. The putative reproductive organs constituting the single Australian specimen of J. hillii are re-interpreted to constitute a broad area of preservational damage on the leaf, hence Jambadostrobus is considered to be a nomen illegitimum.  相似文献   

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The study of imprints of fossil plants collected in the Permian from the country of Hammanskraal (Namibia) leads to the following identifications: Glossopteris sp., Gangamopteris sp., Noegerrathiopsis sp., Gondwanidium sp., Asterotheca sp. and Lycopodiopsis derbyiB. Renault, Lycopodiopsis costilatus n. sp., Brasilodendron pedroanum(W. Carruthers) W.G. Chaloner & alii, Brasilodendron africanum n. sp. This flora has affinities with some fossil floras from South Africa and from Brazil, and is, probably, of upper Permian age.  相似文献   

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A new scelionine genus Indiscelio Veenakumari, Popovici and Talamas is described from India with type species Indiscelio aulon Veenakumari, Popovici and Talamas. Both sexes are described and imaged. Affinities with morphologically similar genera are discussed.  相似文献   

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A recent targeted entomological survey in the Republic of Rwanda has produced two conspecific male and female specimens of an undescribed species of praying mantis (Mantodea). The specimens were collected in Nyungwe National Park in May of 2013. The species is closest morphologically to Dystacta alticeps (Schaum, 1853). Therefore, a new species is described, Dystacta tigrifrutex sp. n., along with the first instar nymphs and ootheca. In addition, the previously monotypic genus Dystacta Saussure, 1871 is re-described to provide a broader definition of the genus group. Habitus images, measurement data, a key to species, natural history information, and locality data are provided.  相似文献   

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Macrodarumoides petalinus, a new genus and species of Issidae (Hemiptera) are described based on specimens from Yunnan and Guangxi, China.  相似文献   

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