The ultrastructure and taxonomy of Diacronema vlkianum (Prymnesiophyceae) with special reference to the haptonema and flagellar apparatus

1977 ◽  
Vol 57 (4) ◽  
pp. 1125-1136 ◽  
Author(s):  
J. C. Green ◽  
D. J. Hibberd
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Special Reference ◽  
Optical Microscopy ◽  
Fresh Water ◽  
Flagellar Apparatus ◽  
Taxonomic Position ◽  
New Family ◽  
Shadow Cast ◽  
Living Material

The taxonomic position of the golden-brown flagellate Diacronema vlkianum Prauser has hitherto been uncertain. It was first reported by Vlk (1938) from fresh water and a brief description given, particular interest being ascribed to the flagella which staining and light microscopy indicated to be without appendages. Because of this Vlk concluded that the organism, which he did not name, occupied a taxonomic niche somewhat apart from typical chrysophytes. In 1958, Prauser isolated, also from fresh water, a flagellate which he identified as Vlk's organism and he described it using both electron microscopy of shadow-cast cells and optical microscopy of living material. He confirmed the lack of flagellar hairs and discussed the taxonomy of Diacronema in relation to both the Ochromonadales with heterokont flagella and the genus Chrysochromulina Lackey with equal smooth flagella. He suggested that the genus could be thought of as representing a new family, the Diacronemataceae, arising from an ochromonad stock and possibly representing a unique line within the chrysomonads.

Investigation of taxonomically important morphological features of endoparasitic bat flies of the subfamily Ascodipterinae (Diptera: Streblidae) by scanning electron microscopy

Zootaxa ◽  
2006 ◽  
Vol 1122 (1) ◽  
pp. 57 ◽  
Author(s):  
MICHAEL W. HASTRITER ◽  
KATHARINA DITTMAR ◽  
MICHAEL F. WHITING
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Morphological Features ◽  
Taxonomic Position ◽  
Old World ◽  
Bat Flies ◽  
Molecular Information ◽  
Scanning Electron

Endoparasitic dealate females of Ascodipteron and an undescribed genus of Ascodipterinae are examined by scanning electron microscopy. The unique morphology of the head and mouth parts and terminal segments are displayed and discussed. Prior reports have focused only on details observable with light microscopy. The taxonomic position of members of the subfamily Ascodipterinae relative to the Old World families of Streblidae and Nycteribiidae is briefly discussed in light of previously published molecular information.

Eliminate Optical Microscopy

2011 ◽  
Vol 19 (4) ◽  
pp. 7-7
Author(s):  
Charles Lyman
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Optical Microscopy ◽  
Special Issue ◽  
Probe Microscopy ◽  
Scanned Probe Microscopy

This special issue of Microscopy Today is devoted to light microscopy. Light microscopy is microscopy that employs light as a medium, or so I thought. Every week I see “optical microscopy” used as a synonym for light microscopy. I cannot understand the popularity of this confusing term. For people outside our field, the term “optical microscopy” must be perplexing: does it mean electron optical or light optical? My point is that we should present the techniques we use in clear unambiguous language: light microscopy, electron microscopy, scanned probe microscopy, etc. Regardless of logic, there are still strong adherents to the term “optical microscopy.”

Studies on the digestive cycle of the shore crab Carcinus maenas (L.) with special reference to the b cells in the hepatopancreas

1980 ◽  
Vol 60 (4) ◽  
pp. 891-907 ◽  
Author(s):  
S. P. Hopkin ◽  
J. A. Nott
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
B Cells ◽  
Light Microscopy ◽  
Special Reference ◽  
Colloidal Particles ◽  
Carcinus Maenas ◽  
Shore Crab ◽  
X Ray ◽  
Scanning Electron

Aspects of the digestive cycle of Carcinus maenas have been studied by transmission and scanning electron microscopy, X-ray microanalysis and light microscopy. Movements of ingested material have been followed by feeding the crabs with Mytilus edulis (L.) labelled with colloidal particles of gold or thorium oxide.

Observations on the Microanatomy of Coccolithus Pelagicus and Cricosphaera Carterae, With Special Reference to the Origin and Nature of Coccoliths and Scales

1969 ◽  
Vol 49 (1) ◽  
pp. 1-16 ◽  
Author(s):  
I. Manton ◽  
G. F. Leedale
Keyword(s):  
Electron Microscopy ◽  
Life History ◽  
Cell Surface ◽  
Light Microscopy ◽  
Special Reference ◽  
Golgi Body ◽  
Central Pore ◽  
Coccolithus Pelagicus ◽  
Whole Mounts

Coccolith structure, mode of origin and arrangement on the cell surface have been investigated in two marine coccolithophorids, Coccolithus pelagicus (Wall.) Schiller and Cricosphaera carterae (Braarud et Fagerland) Braarud, by means of light microscopy and electron microscopy of whole mounts and sections. The presence of flagellar bases in Coccolithus pelagicus is also demonstrated in spite of the fact that the cells of this phase of the life-history are non-motile. In both organisms the coccoliths are shown to be accompanied by unmineralized scales, details of which are illustrated; in particular, each coccolith is attached to the margin of an unmineralized oval plate which completely covers the central ‘pore’ on the side towards the subtending cell. Scales and coccoliths arise within the cisternae of the single Golgi body in a manner closely resembling the origin of scales in species of Chrysochromulina. It is therefore suggested that the coccoliths of the two taxa investigated can be interpreted as modified (and calcined) scale rims.

scholarly journals Through A Cracked Lens: Alternate Views Of Light Microscopy. Part I: Why Does My Microscope Have A Pupil?

1995 ◽  
Vol 3 (7) ◽  
pp. 10-13
Author(s):  
Mark W. Lund
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Optical Microscopy ◽  
Optical Engineer ◽  
Optical Instruments ◽  
Glass Lenses

Let's face it, optics is a fascinating field, but it can bore you to death. My purpose in writing these articles is to show that there are simple, intuitive ways to look at microscopes that can illuminate rather than bore. I have been an optical engineer for many years and have observed many unique ways of looking at optical instruments. I hope that I can share my enthusiasm and insight for light and its manipulation and give some insights that microscopisis may have missed. The microscope is particularly interesting because the glass lenses often do more than one job at the same time. Most of the principles of optical microscopy are directly transferable to electron microscopy, and I will point out specific cases as I go along.

scholarly journals Taxonomic position and glochidia from the freshwater mussel, Anodonta luteola (Unionoida: Unionidae), in Costa Rica

2017 ◽  
Vol 9 (1) ◽  
pp. 39-43
Author(s):  
Rafael A. Cruz ◽  
Rebeca Quesada
Keyword(s):  
Electron Microscopy ◽  
Costa Rica ◽  
Light Microscopy ◽  
Oreochromis Niloticus ◽  
Freshwater Mussel ◽  
Taxonomic Position ◽  
Total Length

Glochidia larvae from Anodonta luteola were observed in gills of Oreochromis niloticus from a farm in Cañas, Guanacaste. Samples  were taken and analyzed by electron microscopy (SEM) and light microscopy. Glochidia were 311, 8μm total length (TL), 331,7μm totalheight (TH), and 251,1μm hinge dorsal length (HDL). Anodonta has 21species reported for the Panamica province, and A. luteola has five synonyms, often used in different reports.

scholarly journals Further Observations on the Fine Structure of Chrysochromulina Minor and C. Kappa with Special Reference to the Pyrenoids

1961 ◽  
Vol 41 (2) ◽  
pp. 519-526 ◽  
Author(s):  
I. Manton ◽  
G. F. Leedale
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Special Reference ◽  
Direct Evidence ◽  
Living Cells ◽  
Marine Plankton ◽  
Thin Sections ◽  
Golgi Structure

Chrysochromulina minor and C. kappa have been re-investigated by means of electron microscopy of thin sections to add details of the microanatomy of pyrenoids and haptonemata, and by anoptral contrast light microscopy to study pyrenoids in living cells. In both species the pyrenoid is in the form of a diverticulum projecting from the centre of the inner face of a plastid and, in C. minor, strongly flexed to lie along it. In C. kappa the pyrenoid is commonly enveloped by the nucleus which may conceal it entirely from view in life. Some details of the behaviour of the surface membranes of plastids and pyrenoids in relation to that of the nucleus are given. The haptonema structure in both species is shown to be comparable to that of others in which this appendage is much longer, though an occasional variant with eight instead of seven central fibres or tubes has been encountered in C. kappa and is demonstrated. The presence of ‘peculiar’ Golgi structure is reported for both species and demonstrated for C. kappa. Some direct evidence indicating an internal origin of scales from vesicles is demonstrated in C. minor. Finally a summary is given of salient structural criteria for all the described species attributed to this genus from the marine plankton, the closest agreement as regards pyrenoid structure in the two species under investigation being with C. chiton.

scholarly journals Calymperaceae, a new family to the bryological flora of Uruguay

2020 ◽  
Vol 55 (3) ◽  
pp. 359-367
Author(s):  
Richard A Cabral ◽  
Maria S. Jimenez ◽  
Guillermo M. Suárez
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
National Park ◽  
Distribution Map ◽  
New Family ◽  
First Time ◽  
Scanning Electron

Background and aims. The aim of this work was to increase the knowledge of the bryoflora in Uruguay based on the analysis of samples collected in Fortaleza Santa Teresa National Park (Uruguay). M&M. Specimens were collected, processed and analyzed morphologically using conventional techniques for bryophytes. Microscopic characters were observed and illustrated with light microscopy (LM) and scanning electron microscopy (SEM). Results. Calymperaceae Kindb. is recorded for the first time to the country, represented by Syrrhopodon gaudichaudii Mont. This species is characterized by leaves strongly crispate when dry, and margins smooth to dentate at the apex. Conclusions. A detailed description, illustrations with SEM and LM, and a distribution map of S. gaudichaudii is here presented.

Ultrastructure of the buccal capsule of the equine nematode Strongylus vulgaris with special reference to the dorsal gutter

1998 ◽  
Vol 72 (2) ◽  
pp. 167-177 ◽  
Author(s):  
M.S. Mobarak ◽  
M.F. Ryan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Special Reference ◽  
Preliminary Data ◽  
Buccal Capsule ◽  
Oesophageal Gland ◽  
Transmission Electron ◽  
Strongylus Vulgaris

AbstractEarly studies by light microscopy provided preliminary data on the fine structure of Strongylus vulgaris (Looss 1900). The present study employed transmission electron microscopy to investigate particular structures in the buccal capsule especially the dorsal gutter (DG) and teeth. The DG is a tube containing the terminal duct of the dorsal oesophageal gland (DOG) surrounded by two concentric canals. Putative pores indicated in the wall of the DG seen in other studies are revealed as honey-combed, fibrous, structures on each side of the ventral lamella. This lamella is formed by the wall of the DG internal canal running the length of the DG. Secretions of the DG canals are released through the dorsal gutter duct (DGD) which passes through the teeth bases at the base of the buccal capsule. Teeth have a vesicular cytoplasmic core containing various organelles.

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