scholarly journals The species of Mentzelia (Loasaceae) in Mexico, part 2: Mentzelia section Bartonia

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
John Schenk ◽  
Carolina Granados Mendoza ◽  
Andres Eduardo Estrada-Castillón
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Species Diversity ◽  
North America ◽  
Species Identification ◽  
Seed Coat ◽  
Western North America ◽  
Distribution Ranges ◽  
Scanning Electron ◽  
Study Species

Background: Mentzelia (Loasaceae) is primarily distributed in western North America. The genus is classified into six monophyletic sections, among which species of section Bartonia are particularly poorly understood. Questions: What species of Mentzelia section Bartonia occur in Mexico? What are the species distribution ranges and what are their defining attributes? Study species: Mentzelia section Bartonia. Methods: Field, herbarium, distribution, and scanning electron microscopy studies were conducted to assess species diversity. Seed coat microsculpture patterns were evaluated to confirm species identities and understand their distributions throughout Mexico. Results: Six species from section Bartonia were recognized, with taxa distributed into either the Chihuahuan or Sonoran deserts. Mentzelia longiloba var. pinacatensis is the only Mexican endemic. Conclusions: Although this work comprehensively addressed the species of section Bartonia in Mexico, two groups will continue to present identification challenges: the M. longiloba and M. mexicana-M. saxicola complexes. Overlapping and variable characters will continue to complicate species identification in the M. longiloba complex, while the late-season loss of primary leaves will obscure species identification between M. mexicana and M. saxicola.

scholarly journals The species of Mentzelia (Loasaceae) in Mexico, part 1: Sectional diversity

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
John Schenk ◽  
Carolina Granados Mendoza ◽  
Andres Eduardo Estrada-Castillón
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
North America ◽  
Species Distributions ◽  
Distribution Patterns ◽  
Species Boundaries ◽  
Western North America ◽  
Species Complexes ◽  
Scanning Electron ◽  
Study Species

Background: Mentzelia (Loasaceae) is a genus of approximately 95 species that are largely distributed in western North America; however, much ambiguity remains regarding species in Mexico. Questions: What species of Mentzelia occur in Mexico and how can they be distinguished? Study species: Mentzelia Methods: Fieldwork, herbarium studies and scanning electron microscopy were carried out to determine the diversity of Mentzelia species in Mexico. Results: Twenty-five species of Mentzelia occur in Mexico, of which four taxa are endemic to the country. Five of the six sections of Mentzelia occur in Mexico. Mentzelia section Mentzelia was the most species rich in Mexico (8 spp.), followed by section Trachyphytum (7 spp.), section Bartonia (6 spp.), section Bicuspidaria (3 spp.), and section Dendromentzelia (1 sp.). The sections have different distribution patterns, with some restricted to few areas and one widespread across most of Mexico. Conclusions: This study is the first treatment of Mentzelia that encompasses all species and regions of Mexico, which includes approximately 26 % of the worldwide Mentzelia species. In-depth studies of the species in the region are needed to abate gaps in our knowledge on the extent of species distributions and to clarify species boundaries among some problematic species complexes.

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 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 Seed morphology and anatomy of Hypericum elegans Steph. ex Willd.

2014 ◽  
Vol 35 (1) ◽  
pp. 15-18
Author(s):  
Piotr Szkudlarz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Eastern Europe ◽  
Seed Coat ◽  
Central And Eastern Europe ◽  
Seed Morphology ◽  
Seed Sample ◽  
Cell Layers ◽  
Mature Seeds ◽  
Scanning Electron

Abstract Hypericum elegans is a rare perennial distributed primarily in Central and Eastern Europe. Seed morphology and anatomy in H. elegans was studied on the basis of a seed sample from its only locality in Poland. Scanning electron microscopy revealed that the seed coat of mature seeds is composed basically of 3 cell layers: epidermal, subepidermal and sclerenchymatic. They are documented graphically here.

Elemental Analysis of Alkalis and Dental Deposits Associated with Coca Chewing in Ecuador

2006 ◽  
Vol 17 (1) ◽  
pp. 77-89 ◽  
Author(s):  
Douglas H. Ubelaker ◽  
Karen E. Stothert
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Spectral Analysis ◽  
North America ◽  
Elemental Analysis ◽  
X Ray ◽  
Tooth Structure ◽  
Elemental Analyses ◽  
The Relationship ◽  
Scanning Electron

AbstractThe relationship between Andean coca use and dental deposits is explored through the use of scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Elemental analyses of samples of large dental deposits from archeologically recovered skeletons from Ecuador dating between 500 B.C. and A.D. 1532 are compared with those of normal calculus deposits of individuals from North America (modern and precontact), of normal tooth structure and of samples of alkali recovered from Ecuadorian artifacts thought to have been employed in coca use. Spectral analysis revealed homogeneity among all dental samples (deposits and structure) and that they are distinct from the elemental pattern revealed in the analysis of the artifact alkalis.

Scanning electron microscopy of Anopheles hyrcanus group (Diptera: Culicidae) eggs in Thailand and an ultrastructural key for species identification

2013 ◽  
Vol 113 (3) ◽  
pp. 973-981 ◽  
Author(s):  
Atiporn Saeung ◽  
Chayanit Hempolchom ◽  
Thippawan Yasanga ◽  
Yasushi Otsuka ◽  
Sorawat Thongsahuan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Species Identification ◽  
Scanning Electron

scholarly journals Molecular phylogeny and morphologic data of strains of the genus Coelastrella (Chlorophyta, Scenedesmaceae) from a tropical region in North America (Yucatan Peninsula)

2017 ◽  
Vol 95 (3) ◽  
pp. 527 ◽  
Author(s):  
Katia Ancona-Canché ◽  
Silvia López-Adrián ◽  
Margarita Espinosa-Aguilar ◽  
Gloria Garduño-Solórzano ◽  
Tanit Toledano-Thompson ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phenotypic Plasticity ◽  
North America ◽  
Yucatan Peninsula ◽  
Tropical Region ◽  
Its2 Rdna ◽  
Yucatán Peninsula ◽  
Good Support ◽  
Scanning Electron

<p><strong>Background: </strong>Scenedesmaceae family exhibits great morphological variability. High phenotypic plasticity and the presence of cryptic species have resulted in taxonomic re-assignments of Scenedesmaceae members.</p><p><strong>Study strains: </strong><strong>S</strong>trains CORE-1, CORE-2 and CORE-3 were characterized.</p><p><strong>Study site: </strong>Yucatan Peninsula</p><p><strong>Methods: </strong><strong>Morphological analyses were executed by optical and scanning electron microscopy. P</strong>hylogenetic relationships were examined by ITS-2 and ITS1-5.8S-ITS2 rDNA regions.<strong></strong></p><p><strong>Results:</strong> Optical and scanning electron microscopy analyses indicated spherical to ellipsoidal cells and autospore formation correspond to members of the family Scenedesmaceae, as well as observable pyrenoid starch plates. Detailed morphology analysis indicated that CORE-1 had visible granulations dispersed on the cell wall, suggesting identity with <em>Verrucodesmus verrucosus</em>. However CORE-1 did not show genetic relations with this species, and was instead clustered close to the genus <em>Coelastrella</em>. CORE-2 did not show any particular structure or ornamentation, but it did show genetic relations with <em>Coelastrella</em> with good support. CORE-3 showed meridional ribs from end to end, one of them forked and well pronounced, and orange cells in older cultures characteristic of <em>Coelastrella</em> specimens. Phylogenetic trees of ITS-2 and ITS1-5.8S-ITS2 rDNA sequences indicated with good support that all strains were related to the genus <em>Coelastrella</em> despite their morphologic differences.</p><p><strong>Conclusions: </strong>This study reports freshwater <em>Coelastrella</em> strains from a tropical region in North America (Yucatan Peninsula) for the first time. The results contribute to knowledge of <em>Coelastrella</em> species, and the fact that they do not always show structures that are useful for taxonomic assignment, probably as a result of phenotypic plasticity.</p>

Taxonomy of the genus Craspedomerus Bernhauer, 1911 (Coleoptera: Staphylinidae: Philonthina) from China

Zootaxa ◽  
2010 ◽  
Vol 2506 (1) ◽  
pp. 1 ◽  
Author(s):  
LIANG LI ◽  
HONG-ZHANG ZHOU
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Species Identification ◽  
Geographical Distribution ◽  
Additional Species ◽  
Three New Species ◽  
First Time ◽  
Scanning Electron

Three new species of the genus Craspedomerus from China are described and illustrated: C. giganteus Li & Zhou sp. n. from Sichuan, C. gongshanus Li & Zhou sp. n. from Yunnan and C. zhangi Li & Zhou sp. n. from Tibet. Four species are reported for the first time from China: C. sinetuber (Coiffait, 1977a) from Tibet, C. cyanipennis Scheerpeltz, 1976b, C. ganeshensis Coiffait, 1983 and C. glenoides (Schubert, 1908) from Yunnan. These four and two additional species previously recorded from China (C. beckeri Bernhauer, 1934 and C. violaceipennis Cameron, 1928 are redescribed and illustrated. Sensory peg setae located on the underside of the paramere of the aedeagus of all nine Chinese species are compared using scanning electron microscopy (SEM) and the result shows that this character is useful for species identification. A key to the Chinese species of Craspedomerus is presented and geographical distribution of all sixteen species of Craspedomerus is mapped.

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