Four new Mallomonas species of the Torquatae series (Chrysophyceae)

1984 ◽  
Vol 62 (8) ◽  
pp. 1583-1591 ◽  
Author(s):  
K. H. Nicholls
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Scale Structure ◽  
Transmission Electron ◽  
Silica Scale ◽  
Constant Structure

Four new species of Mallomonas (Chrysophyceae), Mallomonas scrobiculata sp. nov., Mallomonas serrata sp. nov., Mallomonas labrinthina sp. nov., and Mallomonas favosa sp. nov., are described from transmission electron microscopy of silica-scale structure of specimens from lakes and ponds in Ontario, Canada. All four are of the Torquatae series (characterized by the uniquely shaped anterior collar scales with attached bristles and rhomboidal body scales lacking bristles) and are distinguished from others in the series (e.g., M. mangofera Harris & Bradley, M. alveolata Dürrschmidt, and M. pumilio H. & B. em. Asm. Cronb. & Dürrs.) by the distinctive (and constant) structure and ornamentation of their scales.

Mallomonas lusca sp. nov. (Synurales, Chrysophyceae)—a rare species from Southeast Asia

Phytotaxa ◽  
2021 ◽  
Vol 529 (1) ◽  
pp. 105-112
Author(s):  
EVGENIY GUSEV ◽  
ELENA KEZLYA
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Southeast Asia ◽  
Rare Species ◽  
Central Area ◽  
Scale Morphology ◽  
Transmission Electron ◽  
Silica Scale ◽  
A New Species

A new species of tropical chrysophyte algae, Mallomonas lusca sp. nov. is described from Vietnam based on silica-scale morphology observed using scanning and transmission electron microscopy. Scales of this species were previously found in Malaysia, but had not yet been described. Mallomonas lusca belongs to section Torquatae and is most similar to M. favosa. Its scales have a unique conspicuous rounded pit with a raised thickened central area, which develops in association with the posterior pore in the angle of the posterior submarginal rib. This rounded pit is surrounded by delicate papillae across the border on the shield. Mallomonas lusca has been observed in six localities in Vietnam and one in Malaysia.

Mallomonas parvula sp. nov. and Mallomonas retifera sp. nov. (Chrysophyceae, Synuraceae) from South Chile

1982 ◽  
Vol 60 (5) ◽  
pp. 651-656 ◽  
Author(s):  
Monika Dürrschmidt
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Freshwater Ponds ◽  
Transmission Electron ◽  
Two New Species

Two new species of the unicellular genus Mallomonas, M. parvula sp. nov. and M. retifera sp. nov., were found in freshwater ponds in the vicinity of Valdivia, South Chile. Scales and bristles of the silica armour have been studied by means of scanning and transmission electron microscopy.

Scale structure and taxonomy of some species of Raphidocystis, Raphidiophrys, and Pompholyxophrys (Heliozoea) including descriptions of six new taxa

1985 ◽  
Vol 63 (8) ◽  
pp. 1944-1961 ◽  
Author(s):  
K. H. Nicholls ◽  
M. Dürrschmidt
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Zealand ◽  
Light Microscopy ◽  
Light And Electron Microscopy ◽  
Scale Structure ◽  
Taxonomic Descriptions ◽  
Transmission Electron ◽  
New Information ◽  
Freshwater Habitats

Sixteen taxa of the genera Raphidocystis, Raphidiophrys, and Pompholyxophrys from freshwater habitats in Canada, Chile, and New Zealand were studied by light and electron microscopy. Six taxa are described as new: Raphidocystis glabra, Raphidiophrys minuta, Raphidiophrys orbicularis ssp. orbicularis, R. orbicularis ssp. ovalis, Pompholyxophrys stellata, and P. ossea. New information on scale structure and arrangement based on scanning and transmission electron microscopy amplifies the taxonomic descriptions of Raphidiophrys ambigua, R. pallida, R. elegans, R. intermedia, R. marginata, R. symmetrica, Pompholyxophrys punicea, P. exigua, and P. ovuligera, which were previously imperfectly known by light microscopy only.

A new species of aplanosporic Haptoglossa, H. beakesii, with vesiculate spore release

Botany ◽  
2010 ◽  
Vol 88 (1) ◽  
pp. 93-101 ◽  
Author(s):  
S. L. Glockling ◽  
L. C. Serpell
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Light Microscopy ◽  
Dense Body ◽  
Central Nucleus ◽  
Transmission Electron ◽  
Spore Release ◽  
The University ◽  
A New Species

A new species of Haptoglossa , Haptoglossa beakesii sp. nov., a nematode parasite found in a sample of compost and rabbit dung at the University of Sussex campus, is described. The species, which infects nematodes of the genus Rhabditis , is unusual because it releases non-motile spores into a retaining vesicle. Aspects of the development and reproduction of the species are illustrated with light microscopy and transmission electron microscopy (TEM). TEM revealed a typical multinucleate thallus which cleaved into un-walled aplanospore initials. Each aplanospore contained a central nucleus closely surrounded by mitochondria and with peripheral dense body vesicles (DBV) and distinctive, layered, encystment vesicles. Aplanospores were expelled into a fine vesicle which later broke down to release cysts. Cysts germinated to produce infective gun cells.

Taxonomy and ultrastructure of Sinerima, a new genus of diatoms (Bacillariophyta), with a description of a new species, S. marigela

Phytotaxa ◽  
2018 ◽  
Vol 351 (3) ◽  
pp. 197
Author(s):  
ANNA NESTEROVICH ◽  
BETH E. CAISSIE
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Sea Ice ◽  
New Genus ◽  
Surface Sediments ◽  
Monotypic Genus ◽  
Transmission Electron ◽  
Spring Sea Ice ◽  
A New Species

Based on light, scanning and transmission electron microscopy observations, a detailed description of a new marine fultoportulate diatom Sinerima marigela gen. et sp. nov. is presented. This new taxa is rare (<3% of the thanatocoenosis) in surface sediments in the Bering and Chukchi seas, but appears to have an association with high spring sea ice concentrations. The new monotypic genus is distinct due to its 1) lack of rimoportulae, 2) one-layer valves with marginal pseudoloculi, 3) characteristic velum composed of a cluster of short tubes, and 4) central part without either central fultoportulae or an annulus. This set of characters, especially the lack of rimoportulae, makes S. marigela unique and easily distinguishable from other fultoportulate diatoms.

A new haplosclerid sponge species from the Red Sea

2001 ◽  
Vol 81 (6) ◽  
pp. 943-948 ◽  
Author(s):  
Jean Vacelet ◽  
Abdulmohsin Al Sofyani ◽  
Sultan Al Lihaibi ◽  
Jean-Michel Kornprobst
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Species ◽  
Coral Reefs ◽  
Red Sea ◽  
Sponge Species ◽  
Blue Colour ◽  
Transmission Electron ◽  
Cytological Features ◽  
A New Species

A new species of Chalinula (Haplosclerida: Chalinidae), C. saudiensis, is described from the coral reefs of the Red Sea off Jeddah. The new species is remarkable in its vivid blue colour and its bioactivity. Its description includes cytological features in transmission electron microscopy.

scholarly journals Nano-scale characterisation of sheared β” precipitates in a deformed Al-Mg-Si alloy

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Emil Christiansen ◽  
Calin Daniel Marioara ◽  
Bjørn Holmedal ◽  
Odd Sture Hopperstad ◽  
Randi Holmestad
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scale Structure ◽  
Planar Defects ◽  
Nano Scale ◽  
Transmission Electron ◽  
Before And After ◽  
Peak Aged ◽  
Microscopy Techniques

AbstractThis paper compares the nano-scale structure of β” precipitates in a peak-aged Al-Mg-Si alloy before and after deformation. Three complementary advanced transmission electron microscopy techniques are used to reveal the structures and elucidate the interaction between dislocations and β” precipitates. We show that the needle-like and semi-coherent β” precipitates are sheared several times on different planes by dislocations during deformation, with no indications that they are bypassed or looped. Our results show that dislocations cut through precipitates and leave behind planar defects lying on planes inclined to 〈100〉 directions inside the precipitates. The results also indicate that precipitates are sheared in single steps, and the implication of this observation is discussed in terms of slip behaviour.

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