Application of Scanning Electron Microscopy to Myxomycete Taxonomy

Author(s):  
Judith A. Murphy

Taxonomy of the Myxomyoetes has been based primarily on morphological characteristics observed in the light microscope. Although the fruiting stage is sensitive to environmental conditions, most species exhibit a distinctive although variable category, and thus characteristics of this stage have been used for morphological differentiation. There has been and still is, however, much disagreement concerning the classification and relationships between members of this group. Although capillitial and spore morphology are used in taxonomic classifications, because of their small dimensions they are often poorly defined or not visible in the light microscope. These characteristics are easily discernible by surface scanning electron microscopy (SEM). The purpose of this initial study was to investigate appropriate sample preparations and determine if taxonomically valuable information could be provided with the use of SEM.

1981 ◽  
Vol 64 (1) ◽  
pp. 199-224
Author(s):  
John E Kvenberg

Abstract Larval stored product beetle mandibles were studied by comparing images made by scanning electron microscopy with those made by conventional light microscopy. Discussion of morphological characteristics is based on illustrations of 25 species


2020 ◽  
Vol 57 (5) ◽  
pp. 1447-1458 ◽  
Author(s):  
Fernando de Freitas Fernandes ◽  
Ana Cristina Bahia ◽  
Nágila Francinete Costa Secundino ◽  
Paulo Filemon Paolucci Pimenta

Abstract The ultrastructure of the mouthparts of Haematobia irritans (L.) was investigated by scanning electron microscopy. The morphological characteristics of the maxillary palps, labium (prementum and postmentum), labrum, hypopharynx, haustellum, and labellar lobes are described, as well as of the sensilla evidenced on all the surface of the mouthparts, and the set of different positions assumed by the mouth apparatus of this fly. Based on their morphology, 12 well-differentiated sensilla were identified, among three types of cuticular sensilla: trichoidea, coeloconica, and campaniformia. A slight sexual dimorphism in the sensilla patterns found in the mouthparts of H. irritans was evidenced. These observations are discussed with reference to the current literature on the functional morphology of sense organs of Insecta. These results could facilitate the recognition of the chemosensory sensilla by electrophysiological techniques, and foment future taxonomic and phylogenetic studies to better elucidate the evolution of Diptera, Muscomorpha.


2020 ◽  
Vol 11 (2) ◽  
pp. 486-492
Author(s):  
Jens Anibal Juul ◽  
Vegard Asgeir Forsaa ◽  
Tor Paaske Utheim ◽  
Endre Willassen

We present a case report of periocular Loa loa. The key feature of L. loa distinguishing it from other human filarial parasites are cuticular bosses, which are presented in images from a light microscope and a scanning electron microscope. The cuticular bosses could be divided into three subtypes not previously described.


Cancers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 416 ◽  
Author(s):  
Afroditi Nanou ◽  
Mateus Crespo ◽  
Penny Flohr ◽  
Johann De Bono ◽  
Leon Terstappen

To explore morphological features of circulating tumor cells (CTCs) and tumor-derived extracellular vesicles (tdEVs), we developed a protocol for scanning electron microscopy (SEM) of CTCs and tdEVs. CTCs and tdEVs were isolated by immunomagnetic enrichment based on their Epithelial Cell Adhesion Molecule (EpCAM) expression or by physical separation through 5 μm microsieves from 7.5 mL of blood from Castration-Resistant Prostate Cancer (CRPC) patients. Protocols were optimized using blood samples of healthy donors spiked with PC3 and LNCaP cell lines. CTCs and tdEVs were identified among the enriched cells by fluorescence microscopy. The positions of DNA+, CK+, CD45− CTCs and DNA−, CK+, CD45− tdEVs on the CellSearch cartridges and microsieves were recorded. After gradual dehydration and chemical drying, the regions of interest were imaged by SEM. CellSearch CTCs retained their morphology revealing various shapes, some of which were clearly associated with CTCs undergoing apoptosis. The ferrofluid was clearly distinguishable, shielding major portions of all isolated objects. CTCs and leukocytes on microsieves were clearly visible, but revealed physical damage attributed to the physical forces that cells exhibit while entering one or multiple pores. tdEVs could not be identified on the microsieves as they passed through the pores. Insights on the underlying mechanism of each isolation technique could be obtained. Complete detailed morphological characteristics of CTCs are, however, masked by both techniques.


Phytotaxa ◽  
2015 ◽  
Vol 237 (1) ◽  
pp. 1 ◽  
Author(s):  
Xin-Mao Zhou ◽  
Li-Jü Jiang ◽  
Liang Zhang ◽  
Xin-Fen Gao ◽  
Zhao-Rong He ◽  
...  

Using light microscope (LM) and scanning electron microscope (SEM), the megaspores and microspores of 77 samples representing ca. 70 species of Selaginella from China are observed. Combing previous studies, the spore morphology of nearly all documented Selaginella species from China were reviewed. Based on the morphological characteristics in megaspores and/or microspores, we divided the spores of Chinese species into 15 types and three types are further divided into various subtypes. Each type and subtype are described in detail and a key to the types and subtypes of spores is given. For the first time, the systematic significance of microspores of Selaginella are discussed, and the results indicate that microspores of Selaginella are significant in the systematics of Selaginella. Some important morphological characteristics in spores (e.g., color, micro-sculpture, size, etc.), often been neglected in previous studies, are introduced. Some spore-morphological synapomorphies of the clades and subclades, identified by recent molecular work (Zhou et al. 2015a), are well established. Using the spore morphology, the delimitation of some taxonomically difficult species in Selaginella is assessed.


1980 ◽  
Vol 58 (23) ◽  
pp. 2454-2458 ◽  
Author(s):  
J. A. Traquair ◽  
E. G. Kokko

Coleosporium plumeriae Pat. is a rust fungus (Melampsoraceae) found on Plumeria species. The spermagonial and aecial states are unknown. Light and scanning electron microscopy of uredinia have revealed catenulate, verrucose urediniospores with scattered germ pores. We expect that, as in other Coleosporium species, the urediniospores are morphologically similar to aeciospores. The urediniospore ornamentation consists of distinctive, annulate, bluntly capitate tubercles. Light microscopy of telia indicates that teliospores are smooth, gelatinous, and one celled, quickly appearing four celled with division of the protoplast into an internal four-celled basidium.


1985 ◽  
Vol 63 (12) ◽  
pp. 2357-2363 ◽  
Author(s):  
M. J. C. Rhodes ◽  
R. J. Robins ◽  
R. J. Turner ◽  
J. I. Smith

The surface features of plant cells immobilised in a matrix of either reticulated polyurethane foam or nylon fibre have been examined with the scanning electron microscope. It has been found that both cells and matrix are enveloped in a thin film, the appearance of which is very dependent on the method by which material is prepared for scanning electron microscopy. The structure is severely damaged by fixation and dehydration. Only in specimens examined in the frozen hydrated state is a structure seen compatible with that observed with the light microscope. From the way the appearance of the film is affected by different methods of preparation for the scanning electron microscope, it is suggested that the film is a hydrated mucilage. The importance of this film for the retention of cells within the matrix is discussed.


2015 ◽  
Vol 68 (1-2) ◽  
pp. 10-16
Author(s):  
Milan Drobac ◽  
Igor Stojanac ◽  
Bojana Ramic ◽  
Milica Premovic ◽  
Ljubomir Petrovic

Introduction. The ultimate goal in restorative dentistry has always been to achieve strong and permanent bond between the dental tissues and filling materials. It is not easy to achieve this task because the bonding process is different for enamel and dentin - dentin is more humid and more organic than enamel. It is moisture and organic nature of dentin that make this hard tissue very complex to achieve adhesive bond. One of the first and most widely used tools for examining the adhesive bond between hard dental tissues and composite restorative materials is scanning electron microscopy. The aim of this study was scanning electron microscopy analyzes the interfacial micro morphology of total-etch and self-etch adhesives. Material and Methods. Micro morphological characteristics of interface between totaletch adhesive (Prime & Bond NT) in combination with the corresponding composite (Ceram X Mono) were compared with those of self-etching adhesive (AdheSE One) in combination with the corresponding composite (Tetric EvoCeram). The specimens were observed under 1000 x magnification of scanning electron microscopy (JEOL, JSM-6460 Low Vacuum). Measurement of the thickness of the hybrid layer of the examined composite systems was performed with the software of the device used (NIH Image ?nalyser). Results. Micromorphological analysis of interface showed that the hybrid layer in sound dentin was well formed, its average thickness being 2.68 ?m, with a large number of resin tags and a large amount of lateral branches for specimens with a composite system Prime & Bond NT - Ceram X Mono. However, the specimens with composite systems Adhese One - Tetric EvoCeram did not show the presence of hybrid layer and the resin tags were poorly represented. Conclusion. The results of this study suggest that total-etch adhesives bond better with sound dentin than self-etch adhesives.


Sign in / Sign up

Export Citation Format

Share Document