scholarly journals A new iridescent corticolous myxomycete species (Licea: Liceaceae: Liceales) and crystals on American elm tree bark in Texas, U.S.A.

2019 ◽  
Vol 13 (2) ◽  
pp. 367-386
Author(s):  
Harold W. Keller ◽  
Vanessa M. Marshall
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscope ◽  
Unknown Origin ◽  
Morphological Characters ◽  
Tree Bark ◽  
Depth Of Field ◽  
Coffee Bean ◽  
American Elm ◽  
Scanning Electron

A Licea species new to science is described on the bark surface of living American elm (Ulmus americana L.) cultured in moist chambers. It is characterized by an iridescent peridium on the sides of the sporangium, a black apical circular patch of globular debris, and dark reddish black spores that are smooth over half the surface and ridged-reticulate over the other half with the paler thinner wall collapsing into a coffee-bean shape. This combination of morphological characters is distinct and separates this taxon from all other species of Licea. The history of moist chamber culture use and field collection of corticolous myxomycetes is reviewed. The discovery of crystals of unknown origin on the bark surface of American elms associated with Licea species are illustrated with light microscope photography and scanning electron microscopy. Light microscope images and habit photographs were made using multi-focus imaging and computer stacking to increase depth of field and provide illustrations in color of sporangial structures of the new Licea species. This tiny short-stalked Licea approximately 100 um in height, and with distinctive external and internal morphological characters, was photographed using scanning electron microscopy. Dark-spored versus light-spored species of Licea are reviewed and compared with the most recent molecular analysis as this relates to the genus Licea. This paper is the first in a series that will document the discovery of Licea fruiting bodies of four new species on American elms in nature parks near Fort Worth, Texas.

Phasmids in Tylenchulidae (Tylenchida: Criconematoidea)

Nematology ◽  
2005 ◽  
Vol 7 (2) ◽  
pp. 249-252 ◽  
Author(s):  
Etienne Geraert ◽  
Dieter Sturhan
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscope ◽  
First Record ◽  
Morphological Characters ◽  
Systematic Position ◽  
Tail Region ◽  
Family Presence ◽  
Basal Position ◽  
Scanning Electron

AbstractLight-microscope studies revealed the presence of phasmids in the mid-tail region in species of the genera Tylenchulus, Trophotylenchulus (syn. Trophonema), Sphaeronema and Meloidoderita in Tylenchulidae. Scanning electron microscopy studies on Sphaeronema species verified these observations. Absence of phasmids or phasmid-like structures was confirmed for genera placed in Paratylenchinae and Tylenchocriconematinae in the same family, and for other taxa of Criconematoidea. This first record of phasmids in the superfamily Criconematoidea requires reconsideration of the systematic position of Tylenchulidae and of the relationships of the genera currently placed in this family. Presence of phasmids, deirids and other morphological characters place Tylenchulidae in a basal position in Criconematoidea.

Taxonomic application of macro and micro morphological characters of seeds in Astragalus L. (Galegeae, Fabaceae) in India

Phytotaxa ◽  
2021 ◽  
Vol 502 (2) ◽  
pp. 191-207
Author(s):  
SHIVANI KASHYAP ◽  
CHANDAN KUMAR SAHU ◽  
ROHIT KUMAR VERMA ◽  
LAL BABU CHAUDHARY
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Seed Coat ◽  
Morphological Plasticity ◽  
Morphological Characters ◽  
Individual Species ◽  
Large Size ◽  
The Individual ◽  
Scanning Electron

Due to large size and enormous morphological plasticity, the taxonomy of the genus Astragalus is very complex and challenging. The identification and grouping of species chiefly based on macromorphological characters become sometimes difficult in the genus. In the present study, the micromorphology of the seeds of 30 species belonging to 14 sections of Astragalus from India has been examined applying scanning electron microscopy (SEM) along with light microscopy (LM) to evaluate their role in identification and classification. Attention was paid to colour, shape, size and surface of seeds. The overall size of the seeds ranges from 1.5–3.2 × 0.8–2.2 mm. The shape of the seeds is cordiform, deltoid, mitiform, orbicular, ovoid and reniform. The colour of seeds varies from brown to blackish-brown to black. Papillose, reticulate, ribbed, rugulate and stellate patterns were observed on the seed coat surface (spermoderm) among different species. The study reveals that the seed coat ornamentations have evolved differently among species and do not support the subgeneric and sectional divisions of the genus. However, they add an additional feature to the individual species, which may help in identification in combination with other macro-morphological features.

scholarly journals ELECTRON MICROSCOPIC STUDIES OF SOME ANTICANCER PLANTS POLLEN GRAINS

2021 ◽  
Vol 9 (10) ◽  
pp. 1386-1393
Author(s):  
Jayshree Sandesh Thaware ◽  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Morphological Characters ◽  
Electron Microscopic ◽  
Plant Parts ◽  
Morphological Studies ◽  
Datura Metel ◽  
Scanning Electron

Pollen is appropriately referred by some as Golden dust extremely valuable on account of their tremendous applications in science, industries and public health. No other plant part even though extremely tiny in size is packed with so much information and power. Similar to other plant parts, pollen characters are so varied that the classification system of plants can be built up entirely on the basis of pollen morphology.Palynology is the distinct branch of biology that deals with the dispersed microscopic tiny living and fossil entities including pollen grains, spores, algal and fungal fragments and others. An important aspect of Palynology is the Pollen morphology. The importance of Palynology in taxonomic and phylogenetic consideration of plants is well known. The changes occurring through hybridization and years of cultivation are reflected in pollen morphology. The scope and interest in the study of pollen morphology have widened with the advent of Scanning Electron Microscopy (SEM) and with regards to unipalynous taxa particularly the understanding of finer morphology is of fundamental importance. SEM gives a correct understanding of exine surface as the electron photographs of the surface replica of the exine provides the exact picture of the ornamentation pattern. The variation in the pollen morphological characters helps in the classification of plant taxa and their assessment of their phylogenetic relationship. In the present investigation, the pollen morphological studies were carried out of some ethnomedicinal plants like Catharanthus roseus, Allamanda cathartica, Datura metel, Brassica juncea, Raphanus sativus and Cleome viscosa pollen grains by Scanning electron microscopy. All that they possess anticancer characteristics in common.

Field of View and Image Distortion : A Review of Low Magnification Imaging In the Environmental and Conventional Scanning Electron Microscopes (SEM)

1997 ◽  
Vol 3 (S2) ◽  
pp. 1193-1194
Author(s):  
Brendan J. Griffin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Of View ◽  
Depth Of Field ◽  
Aperture Size ◽  
Sem Image ◽  
Electron Microscopes ◽  
Working Distance ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Most scanning electron microscopy is performed at low magnification; applications utilising the large depth of field nature of the SEM image rather than the high resolution aspect. Some environmental SEMs have a particular limitation in that the field of view is restricted by a pressure limiting aperture (PLA) at the beam entry point of the specimen chamber. With the original ElectroScan design, the E-3 model ESEM utilised a 500 urn aperture which gave a very limited field of view (∼550um diameter at a 10mm working distance [WD]). An increase of aperture size to ∼lmm provided an improved but still unsatisfactory field of view. The simplest option to increase the field of view in an ESEM was noted to be a movement of the pressure and field, limiting aperture back towards the scan coils1. This approach increased the field of view to ∼2mm, at a 10mm WD. A commercial low magnification device extended this concept and indicated the attainment of conventional fields of view.

scholarly journals Scanning Electron Microscopy Observations of Loa loa (Nematoda)

2020 ◽  
Vol 11 (2) ◽  
pp. 486-492
Author(s):  
Jens Anibal Juul ◽  
Vegard Asgeir Forsaa ◽  
Tor Paaske Utheim ◽  
Endre Willassen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Case Report ◽  
Scanning Electron Microscope ◽  
Light Microscope ◽  
Loa Loa ◽  
Scanning Electron

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.

scholarly journals Foliar trichomes of Croton L. (Euphorbiaceae: Crotonoideae) from China and its taxonomic implications

2013 ◽  
Vol 20 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Huan-Fang Liu ◽  
Yun-Fei Deng ◽  
Jing-Ping Liao
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Species Identification ◽  
Morphological Characters ◽  
Plant Taxon ◽  
Taxonomic Implications ◽  
Sectional Classification ◽  
Trichome Types ◽  
Trichome Morphology ◽  
Scanning Electron

Foliar trichomes of 21 species of the genus Croton L. from China have been examined using stereomicroscopy and scanning electron microscopy. Five trichome types characterized by their morphology are identified, viz., stellate, lepidote, simple, dendritic and appressed-rosulate. Only stellate trichome is observed in most species, with only six species that are found to maintain two or three trichome types. Trichome types and density are useful for species identification and sectional classification for Chinese species. Based on the trichome types and other morphological characters, 21 Chinese species are proposed to be placed in five sections. Croton crassifolius belongs to sect. Andrichnia; C. cascarilloides belongs to sect. Monguia; C. mangelong, C. kongensis, C. laevigatus and C. laniflorus belong to sect. Argyrocroton; C. lauioides, C. howii and C. damayeshu belong to sect. Adenophylli. The remaining Chinese Croton species might be placed into sect. Croton. A key for Chinese Croton species based on trichome morphology is provided.DOI: http://dx.doi.org/10.3329/bjpt.v20i1.15468Bangladesh J. Plant Taxon. 20(1): 85-94, 2013 (June)

scholarly journals Mericarp morphology of the tribe Selineae (Apiaceae, Apioideae) and its taxonomic implications in Korea

2018 ◽  
Vol 25 (2) ◽  
pp. 175-186 ◽  
Author(s):  
Changyoung Lee ◽  
Jinki Kim ◽  
Ashwini M. Darshetkar ◽  
Ritesh Kumar Choudhary ◽  
Sang-Hong Park ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Morphological Characters ◽  
Surface Pattern ◽  
Taxonomic Implications ◽  
Scanning Electron

Mericarp morphology of 24 taxa belonging to nine genera of the tribe Selineae (Family: Apiaceae) in Korea was studied by Scanning Electron Microscopy. UPGMA and NMDS analyses were performed based on 12 morphological characters. The mericarp surface characters like mericarp shape, rib number and shape, surface pattern, surface appendages and mericarp symmetry proved useful in distinguishing the genera of the tribe Selineae.

Revised taxonomy and redescription of two species of the Peripatidae (Onychophora) from Brazil: a step towards consistent terminology of morphological characters

Zootaxa ◽  
2010 ◽  
Vol 2493 (1) ◽  
pp. 16 ◽  
Author(s):  
IVO DE SENA OLIVEIRA ◽  
ALFREDO HANNEMANN WIELOCH ◽  
GEORG MAYER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Type Species ◽  
Morphological Characters ◽  
Type Material ◽  
Taxon Sampling ◽  
The Caribbean ◽  
Dermal Papillae ◽  
Scanning Electron

Based on the supposed quadrangular shape of the basal pieces of dorsal primary papillae, several species of the “Caribbean group” of the neotropical Peripatidae, including Macroperipatus acacioi and M. machadoi, were assigned to Macroperipatus. So far, the quadrangular shape of dermal papillae was confirmed only for M. torquatus, the type species of the genus. Previous observations revealed that the putatively quadrangular shape reported from other species of the “Caribbean group” might be a fixation artefact. Hence, detailed reinvestigations of all putative Macroperipatus species are required to clarify their taxonomy. In the present study, two species of the “Caribbean group”, M. acacioi and M. machadoi, are analyzed and redescribed, based on type material and topotype specimens collected at the corresponding type localities. The original descriptions of both species are complemented with data obtained from scanning electron microscopy, in addition to conventional morphological methods. The quadrangular bases of primary papillae are shown to be absent from M. acacioi and M. machadoi, thus suggesting that these two species are not closely related to M. torquatus. The new data instead suggest that these two species are representatives of Epiperipatus: E. acacioi comb. nov. and E. machadoi comb. nov.. The present study highlights the use of scanning electron microscopy for clarifying the taxonomy and phylogeny of the neotropical Peripatidae. It also reveals gaps in taxon sampling and problems regarding the ambiguous terminology of morphological characters used for describing the anatomy of peripatids. An attempt is made towards a consistent terminology for species (re)descriptions and studies of onychophoran anatomy and phylogeny.

Free-living marine planktonic unarmoured dinoflagellates from the Gulf of Mexico and the Mexican Pacific

2015 ◽  
Vol 58 (1) ◽  
Author(s):  
Sergio Escobar-Morales ◽  
David U. Hernández-Becerril
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Gulf Of Mexico ◽  
Species Composition ◽  
New Records ◽  
Morphological Characters ◽  
Phylogenetic Group ◽  
Free Living ◽  
Mexican Pacific ◽  
Scanning Electron

AbstractThe so-called unarmoured dinoflagellates are not a “natural” (phylogenetic) group but they lack thecal plates, share fragility and possess relatively few morphological characters that can be positively identified. This study depicts the species composition of unarmoured dinoflagellates collected from sites along the coasts of the Gulf of Mexico and the Mexican Pacific and includes their descriptions and illustrations. We identified a total of 25 species belonging to 13 genera and six families that were studied through various techniques using light and scanning electron microscopy. Seven new records for the Mexican Pacific are annotated here that include

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