Organic-walled microfossils of the mid-Neoproterozoic Alinya Formation, Officer Basin, Australia

2016 ◽  
Vol 90 (5) ◽  
pp. 854-887 ◽  
Author(s):  
Leigh Anne Riedman ◽  
Susannah Porter
Keyword(s):  
New Combination ◽  
Rapid Decline ◽  
Low Latitude ◽  
Shallow Marine ◽  
Eukaryotic Diversity ◽  
Transmitted Light Microscopy ◽  
Eukaryotic Species ◽  
Morphological Detail ◽  
Microfossil Assemblage ◽  
Scanning Electron

AbstractEstimates of Precambrian eukaryotic diversity and disparity indicate broad trends of increase in the Mesoproterozoic Era, leading to a peak and then rapid decline by ca. 750 Ma. The organic-walled microfossil assemblage presented here is representative of that mid-Neoproterozoic height of eukaryotic species richness. Organic-rich shales and siltstones of the mid-Neoproterozoic upper Alinya Formation, eastern Officer Basin, Australia, preserve an abundant and diverse assemblage of organic-walled microfossils deposited in a low-latitude, shallow marine setting. Use of scanning electron microscopy (SEM) revealed an unexpected level of morphological detail not visible in transmitted light microscopy. This led to the recognition of new species as well as establishment of degradational sequences, which aid in fossil recognition. In total, 26 taxa are described here; these include 21 previously named forms, four newly described species (Caelatimurus foveolatus, Culcitulisphaera revelata, Karenagare alinyaensis, and Morgensternia officerensis), and one new combination (Vidalopalla verrucata).

Scanning and Transmission Electron Microscopy of Human Red Blood Cells

1969 ◽  
Vol 27 ◽  
pp. 44-45
Author(s):  
A.J. Tousimis ◽  
T.R. Padden
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Blood Cells ◽  
Room Temperature ◽  
Type Specimen ◽  
New Combination ◽  
Human Red Blood Cells ◽  
Transmission Electron ◽  
Microscope Slides ◽  
Scanning Electron

The size, shape and surface morphology of human erythrocytes (RBC) were examined by scanning electron microscopy (SEM), of the fixed material directly and by transmission electron microscopy (TEM) of surface replicas to compare the relative merits of these two observational procedures for this type specimen.A sample of human blood was fixed in glutaraldehyde and washed in distilled water by centrifugation. The washed RBC's were spread on freshly cleaved mica and on aluminum coated microscope slides and then air dried at room temperature. The SEM specimens were rotary coated with 150Å of 60:40- gold:palladium alloy in a vacuum evaporator using a new combination spinning and tilting device. The TEM specimens were preshadowed with platinum and then rotary coated with carbon in the same device. After stripping the RBC-Pt-C composite film, the RBC's were dissolved in 2.5N HNO3 followed by 0.2N NaOH leaving the preshadowed surface replicas showing positive topography.

Ascospore sculpturing and generic concepts in the Testudinaceae (syn. Zopfiaceae)

1979 ◽  
Vol 57 (2) ◽  
pp. 91-99 ◽  
Author(s):  
D. L. Hawksworth
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Combination ◽  
The Family ◽  
First Time ◽  
Scanning Electron

Generic concepts in the Testudinaceae (Ascomycotina, Loculoascomycetes) are reviewed with particular emphasis on the sculpturing of the ascospores which has been examined by scanning electron microscopy (SEM) for the first time. A key to the nine genera accepted in the family is provided of which two are described as new: Ulospora for U. bilgramii comb.nov. (= Zopfia bilgramii D. Hawksw. et al.), the ascospores of which have three to six deep fissures in each cell, and Zopfiofoveola for Z. punctata comb.nov. (= Zopfia punctata D. Hawksw. & C. Booth), with distinctly and regularly foveolate ascospores. One further new combination is made: Rechingeriella boudieri comb.nov. (= Zopfia boudieri Arnaud). The positions of three additional genera referred to the family by earlier authors but which are excluded from it here are also briefly discussed.

Chrysophycean stomatocysts from the postglacial sediments of a High Arctic lake

1988 ◽  
Vol 66 (6) ◽  
pp. 1117-1128 ◽  
Author(s):  
Katharine E. Duff ◽  
John P. Smol
Keyword(s):  
Species Composition ◽  
Light Microscopy ◽  
High Arctic ◽  
Ellesmere Island ◽  
Arctic Lakes ◽  
Ecological Research ◽  
Stratigraphic Analysis ◽  
Morphological Detail ◽  
Electron And Light Microscopy ◽  
Scanning Electron

Twenty-six chrysophycean stomatocyst morphotypes were described from the postglacial sediments of a small, rock basin lake near Baird Inlet, Ellesmere Island. Scanning electron and light microscopy were used to classify the stomatocysts, following the guidelines of the International Statospore Working Group. None of the stomatocysts could be related with certainty to the chrysophyte species that produced them, but sufficient morphological detail is present in most of the stomatocysts to allow for taxonomic differentiation. A stratigraphic analysis of the dominant stomatocyst morphotypes revealed that chrysophyte species composition changed most markedly during the lake's early development but then remained relatively constant. This study demonstrated that chrysophycean stomatocysts provide useful paleoecological information in High Arctic lakes, but further taxonomic and ecological research is required to fully exploit these microfossils.

scholarly journals A redescription of the poorly known cave millipede Skleroprotopus membranipedalis Zhang, 1985 (Diplopoda, Julida, Mongoliulidae), with an overview of the genus Skleroprotopus Attems, 1901

2018 ◽  
Vol 26 ◽  
pp. 55-66
Author(s):  
Boyan Vagalinski ◽  
Kaibaryer Meng ◽  
Darina Bachvarova ◽  
Pavel Stoev
Keyword(s):  
Electron Micrographs ◽  
Original Description ◽  
Cloud Water ◽  
Type Locality ◽  
New Combination ◽  
Scanning Electron Micrographs ◽  
Subjective Synonym ◽  
Scanning Electron

We redescribe the poorly known Chinese millipede Skleroprotopusmembranipedalis Zhang, 1985 recorded from Shi-Hua (Stone Flower) Cave, Fangshan County, Beijing. The species’ original description is in Chinese in an obscure outlet which significantly hampers its recognition from its congeners. Here, based on newly collected material, we provide the first scanning electron micrographs of important taxonomic traits. In addition to its type locality, we report the species also from Yun-Shui (Cloud Water) Cave, situated in the same county, some 18 km away. We propose the genus Senbutudoiulus Miyosi, 1957 to be a junior subjective synonym of Skleroprotopus Attems, 1901, syn. n., and introduce the following new combination: Skleroprotopusplatypodus (Miyosi, 1957), comb. n. (former Senbutudoiulus).

Achnanthales from historical Grunow collection in Porto Subzanski, Croatia

2018 ◽  
Vol 61 (6) ◽  
pp. 573-593 ◽  
Author(s):  
Catherine Riaux-Gobin ◽  
Luc Ector ◽  
Andrzej Witkowski ◽  
Anton Igersheim
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Coastal Environment ◽  
New Combination ◽  
Tropical Environments ◽  
A New Species ◽  
Scanning Electron

Abstract In the historical Grunow collection in Vienna, a piece of a broken slide covered with mica contained diatom material from Porto Subzanski, a coastal environment in Croatia. This material was examined in scanning electron microscopy. Several poorly documented or improperly assigned taxa within the Achnanthales, namely in Amphicocconeis and Cocconeis, were re-examined. A new combination of Amphicocconeis and a new species of Cocconeis are proposed. The new species, Cocconeis subzanskiensis, is closely related to Cocconeis placentula, except for the lack of a characteristic hyaline sub-marginal rim on the raphe valve, and is compared with other marine taxa pertaining to the same group. Recently described in tropical environments, Cocconeis coronatoides has been found in the Grunow material.

Studies onTernidens deminutusRailliet & Henry, 1909 (Nematoda) I. External morphology

1973 ◽  
Vol 47 (2) ◽  
pp. 119-126 ◽  
Author(s):  
J. M. Goldsmid ◽  
N. F. Lyons
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Size Range ◽  
Three Dimensional ◽  
Transmitted Light ◽  
External Morphology ◽  
Morphological Studies ◽  
Transmitted Light Microscopy ◽  
Dimensional Picture ◽  
Scanning Electron

The present paper describes the size range ofTernidens deminutusfrom human and baboon hosts in Rhodesia and discusses the possible reasons for the differences noted.Using transmitted light and the scanning electron microscope, the external morphology ofT. deminutushas been re-studied and compared to investigations by other authors using transmitted light microscopy alone.The paper also illustrates the value of the scanning electron microscope in morphological studies in helminthology, especially when used in conjunction with the light microscope, to give an excellent three-dimensional picture of the species under investigation.It is intended to follow this work with further studies on the anatomy, histology, ultrastructure and histochemistry ofTernidens deminutus.

Morphological observations of Aulacoseira using scanning electron microscopy

1997 ◽  
Vol 75 (11) ◽  
pp. 1807-1835 ◽  
Author(s):  
Peter A. Siver ◽  
Hedy Kling
Keyword(s):  
Current Literature ◽  
Common Species ◽  
Additional Source ◽  
Common Component ◽  
Phytoplankton Communities ◽  
Central Canada ◽  
Morphological Detail ◽  
Aulacoseira Granulata ◽  
Scanning Electron ◽  
Made In

Despite the fact that the genus Aulacoseira Thwaites is a common component of phytoplankton communities in many North American water bodies, there are relatively few taxonomic based surveys utilizing the scanning electron microscope (SEM). In addition, based on the current literature, some species are difficult to identify or distinguish from other taxa. We present taxonomic and morphological observations on 19 taxa based primarily on collections made in Connecticut, U.S.A., and from central and northern Canada. Aulacoseira ambigua (Grunow) Simonsen, Aulacoseira subarctica (O. Müller) Haworth, and Aulacoseira tenella (Nygaard) Simonsen were the most common species encountered in Connecticut, while Aulacoseira islandica (O. Müller) Simonsen, Aulacoseira granulata (Ehrenberg) Simonsen, A. subarctica, and A. ambigua were the dominant species from many central Canada localities. In the Canadian Shield region, specimens of the Aulacoseira disions (Ehrenberg) Simonsen group, the Aulacoseira lirata (Ehrenberg) Ross in Hartley group, and Aulacoseira perglabra (Oestrup) Haworth were more common. We had the most difficulty identifying taxa in the A. distorts and A. perglabra complexes and distinguishing A. lirata from Aulacoseira alpigena (Grunow) Krammer. The primary objectives of the paper were to provide an additional source of high-resolution SEM micrographs for many of the more common species of Aulacoseira, comment on the morphological detail of each taxon, and to discuss the difficulties we encountered using the current literature to identify some of the species. A few ecological observations are also provided. Lastly, we propose two new combinations, Aulacoseira pseudoamericana (Camburn) comb.nov. and Aulacoseira distans var. nivaloides (Camburn) comb.nov. Key words: diatoms, Aulacoseira, North America, taxonomy, morphology.

Prestauroneis genkalii—a new diatom species (Bacillariophyceae: Stauroneidaceae) from Southeast Asia

Phytotaxa ◽  
2019 ◽  
Vol 414 (4) ◽  
pp. 156-164
Author(s):  
ANTON GLUSHCHENKO ◽  
JOHN PATRICK KOCIOLEK ◽  
IRINA KUZNETSOVA ◽  
ELENA KEZLYA ◽  
MAXIM KULIKOVSKIY
Keyword(s):  
New Species ◽  
Southeast Asia ◽  
Morphological Features ◽  
New Combination ◽  
Diatom Species ◽  
Outline Shape ◽  
Electron Microscopical ◽  
One New Species ◽  
Scanning Electron

We present light and scanning electron microscopical observations on one new species of Prestauroneis from Vietnam. The new species, Prestauroneis genkalii Glushchenko, Kulikovskiy & Kociolek sp. nov., is described on the basis valve outline, shape of the apices, as well as striae and areolar densities. Morphology of Prestauroneis species, especially with respect to valve outline, is discussed. P. genkalii sp. nov. possesses all of the typical morphological features for the genus, including uniseriate striae covered by internal hymenes, a pseudoseptum at each apex and distal raphe ends extending onto the valve mantle. In addition, a new combination is suggested for Navicula pseudocrucicula Kobayasi, Prestauroneis pseudocrucicula (Kobayasi) Glushchenko, Kulikovskiy & Kociolek comb. nov. on the basis of type description. P. genkalii sp. nov. is the first member of the genus Prestauroneis reported for Southeast Asia.

Stipa ×fallax (Poaceae: Pooideae: Stipeae), a new natural hybrid from Tajikistan, and a new combination in Stipa drobovii

Phytotaxa ◽  
2017 ◽  
Vol 303 (2) ◽  
pp. 141 ◽  
Author(s):  
MARCIN NOBIS ◽  
ARKADIUSZ NOWAK ◽  
AGNIESZKA NOBIS ◽  
SYLWIA NOWAK ◽  
JUSTYNA ŻABICKA ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Central Asia ◽  
Field Observation ◽  
Parental Species ◽  
Pollen Grain ◽  
Numerical Analyses ◽  
New Combination ◽  
Natural Hybrid ◽  
Scanning Electron

Stipa ×fallax nothosp. nov. (Poaceae), from western Pamir Alai Mts (Tajikistan), is described and illustrated. Field observation, numerical analyses of morphology, and pollen grain viability data show that it originated from hybridization between S. drobovii and S. macroglossa subsp. macroglossa, species representing sections Smirnovia and Stipa, respectively. Stipa ×fallax is morphologically close to S. ×alaica and S. ×hissarica, but is distinguished by its shortly pilose lower part of the awn and densely pubescent leaves. Characters distinguishing S. ×fallax from its parental species as well as similar hybrid taxa in section Smirnovia that also grow in Central Asia are presented. The micromorphology of lemmas and leaves of S. ×fallax and its parental species was examined by scanning electron microscopy. We also propose the new combination Stipa drobovii var. iskanderkulica (Tzvelev) M.Nobis & A.Nowak.

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