Female reproductive structures of Umaltolepis Krassilov and associated leaves of Pseudotorellia Florin from the Middle Jurassic of East Siberia, Russia

2021 ◽  
pp. 104412
Author(s):  
Natalya Nosova
Keyword(s):  
Middle Jurassic ◽  
East Siberia ◽  
Reproductive Structures

Discovery of isolated leaves of Marskea (Taxaceae) in the Middle Jurassic sediments of Irkutsk Basin (East Siberia, Russia)

Phytotaxa ◽  
2020 ◽  
Vol 449 (2) ◽  
pp. 164-172
Author(s):  
ANDREY O. FROLOV ◽  
IRINA M. MASHCHUK
Keyword(s):  
New Species ◽  
Central Asia ◽  
Lower Cretaceous ◽  
Middle Jurassic ◽  
East Siberia ◽  
Irkutsk Basin ◽  
The Right ◽  
A New Species

Study of isolated leaf compressions from Prisayan Formation outcrops on the right side of the Irkutsk reservoir resulted in identification of a new species: Marskea cuspidata sp. nov. The species has a strong morphological affinity with M. heeriana N. Nosova et Kiritchkova and T. ketovae Teslenko. The epidermis original texture differs well the Marskea cuspidata sp. nov. from other representatives of the genus Marskea which are known from the Jurassic and Lower Cretaceous sediments of Europe, Central Asia and Siberia.

Female reproductive structures of Ginkgo gomolitzkyana N. Nosova, sp. nov. from the Middle Jurassic of Angren (Uzbekistan)

Palaeobotany ◽  
2012 ◽  
Vol 3 ◽  
pp. 62-91 ◽  
Author(s):  
N. V. Nosova
Keyword(s):  
Middle Jurassic ◽  
Cell Walls ◽  
Outer Integument ◽  
Detailed Comparison ◽  
First Record ◽  
Reproductive Structure ◽  
Reproductive Structures ◽  
Living Species ◽  
Collar Diameter ◽  
Subsidiary Cells

Ovules (seeds) of Ginkgo gomolitzkyana N. Nosova, sp. nov. are described from the Angrenian Formation of the Middle Jurassic in Angren, Uzbekistan. Ovules are attached to pedicels with a collar at bases. Collar diameter of G. gomolitzkyana is similar to that of G. ginkgoidea from the Middle Jurassic of Sweden and G. apodes from the Lower Cretaceous of China. Unfortunately the epidermal structures of the two last species are not described. Epidermal patterns of the outer surface of the collar of G. gomolitzkyana are similar to those of G. yimaensis. Lack of data on the structures of the collar inner surface of G. gomolitzkyana does not allow any detailed comparison. G. yimaensis differs from G. gomolitzkyana by 1.5โ€”2 times larger collar diameter. The ovules (seeds) of G. gomolitzkyana are similar to the ovules (seeds) of G. ginkgoidea, G. yimaensis, G. apodes, G. cranei and Ginkgo sp. (Deng et al., 2004), but they are smaller. The cuticle of the integument and the nucellus cuticle of G. apodes and Ginkgo sp. are not described, what does not allow a comparison with them. G. cranei, unlike G. gomolitzkyana, has thicker outer cuticle of integument and lacking papillae on the subsidiary cells of the stomata. The structures of megaspore membrane are studied only for G. ginkgoidea and G. yimaensis. They are similar to the structures of G. biloba and G. gomolitzkyana. Megaspore membrane of G. ginkgoidea is thicker, than that of G. gomolitzkyana. The dimensions of lacuna and bacula of G. ginkgoidea are not specified. The bacula of the megaspore membrane of G. yimaensis are smaller, than those of G. gomolitzkyana. In addition, G. yimaensis differs from the new species by the curved anticlinal cell walls of the outer integument epidermis. Unlike G. gomolitzkyana anticlinal cell walls of the nucellus of G. ginkgoidea are sometimes sinuous and mostly puncticulate. The seeds of G. biloba are five times larger than seeds of G. gomolitzkyana. The thickness of the outer integument cuticle of the living species is larger and the bacula of the megaspore membrane are thicker. This is the first record of the female reproductive structure of Ginkgo from the Jurassic in the Middle Asia.

OSTRACODS AND BIOSTRATIGRAPHY OF THE LOWER-MIDDLE JURASSIC DEPOSITS OF YAMAL (NORTH OF WEST SIBERIA)

2021 ◽  
pp. 12-20
Author(s):  
L. A. Glinskikh ◽  
Keyword(s):  
Middle Jurassic ◽  
West Siberia ◽  
Yamal Peninsula ◽  
East Siberia ◽  
The West ◽  
Important Species ◽  
Zonal Scale ◽  
Characteristic Species ◽  
The Yamal Peninsula

Ostracods are an effective tool for dissecting and correlating Mesozoic sedimentary strata in closed areas. However, the degree of geologic certainty of ostracods from the marine Lower-Middle Jurassic deposits of West Siberia is very weak. The paper presents the results of monographic and biostratigraphic studies of the Jurassic ostracod complexes of the Yamal Peninsula. 5 stratigraphically important species are described, and images are given for 6 forms. The biostratigraphic division of the Lower and Middle Jurassic of West Siberia by ostracods is substantiated. In the Pliensbachian – Bajocian, a sequence of 6 biostratons was traced by ostracods in the rank of layers with characteristic species: layers with Ogmoconcha longula; with Camptocythere (C.) mandelstami; with Camptocythere (C.) foveolata (established by the author); with Camptocythere (C.) nordvikensis; with Camptocythere (A.) spinulosa; with Camptocythere (A.) arangastachiensis. The West Siberian ostracod biostratons are compared with divisions of the zonal scale for the ostracods of East Siberia, which was developed on natural outcrops of the Jurassic and is сorrelated to the scales for ammonites and other groups of macro- and microfauna.

Freeze substitution fixation of fungal reproductive structures and spores

1989 ◽  
Vol 47 ◽  
pp. 990-991
Author(s):  
C. W. Mims ◽  
E. A. Richardson
Keyword(s):  
Plant Pathogens ◽  
Freeze Substitution ◽  
Uranyl Acetate ◽  
Chemical Fixation ◽  
Dialysis Membrane ◽  
Razor Blade ◽  
Thin Sections ◽  
Reproductive Structures ◽  
Dry Down ◽  
Diamond Knife

The advantages of freeze substitution fixation over conventional chemical fixation for preservation of ultrastructural details in fungi have been discussed by various authors. As most ascomycetes, basidiomycetes and deuteromycetes do not fix well using conventional chemical fixation protocols, freeze substitution has attracted the attention of many individuals interested in fungal ultrastructure. Thus far most workers using this technique on fungi have concentrated on thin walled somatic hyphae. However, in our laboratory we have experimented with the use of freeze substitution on a variety of fungal reproductive structures and spores with promising results.Here we present data on freeze substituted samples of sporangia of the zygomycete Umbellopsis vinacea, basidia of Exobasidium camelliae var. gracilis, developing teliospores of the smut Sporisorium sorghi, germinating teliospores of the rust Gymnosporangium clavipes, germinating conidia of the deuteromycete Cercosporidium personatum, and developing ascospores of Ascodesmis nigricans.Spores of G. clavipes and C. personatum were deposited on moist pieces of sterile dialysis membrane where they hydrated and germinated. Asci of A. nigricans developed on pieces of dialysis membrane lying on nutrient agar plates. U. vinacea was cultured on small pieces of agar-coated wire. In the plant pathogens E. camelliae var. gracilis and S. sorghi, a razor blade was used to remove smal1 pieces of infected host issue. All samples were plunged directly into liquid propane and processed for study according to Hoch.l Samples on dialysis membrane were flat embedded. Serial thin sections were cut using a diamond knife, collected on slot grids, and allowed to dry down onto Formvar coated aluminum racks. Sections were post stained with uranyl acetate and lead citrate.

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