A morphological examination of Frustulia (Bacillariophyceae) from the Ocala National Forest, Florida, USA

2004 ◽  
Vol 82 (5) ◽  
pp. 629-644 ◽  
Author(s):  
Peter A Siver ◽  
George Baskette
Keyword(s):  
Morphological Characters ◽  
Algal Community ◽  
National Forest ◽  
Morphological Examination ◽  
North Central ◽  
Central Florida ◽  
Emended Description ◽  
Components Analysis ◽  
Scanning Electron ◽  
Shape And Size

The genus Frustulia was found to be an abundant and important component of the attached algal community in a suite of dilute, poorly buffered, and acidic ponds situated in the Ocala National Forest in north-central Florida. Six species were found in the study, including Frustulia krammeri Lange-Bertalot & Metzeltin, Frustulia saxonica Raben horst, Frustulia crassinervia (Brébisson) Lange-Bertalot & Krammer, Frustulia pseudomagaliesmontana Camburn & Charles, Frustulia bahlsii Edlund & Brant, and a newly described taxon, Frustulia trochus Siver & Baskette sp. nov. In addition, an emended description is provided for F. pseudomagaliesmontana. Each species was studied in detail with both light and scanning electron microscopy, and the importance of specific morphological characters was also examined with principal components analysis. In addition to valve shape and size, striae density and areolae density, the structure of the helictoglossae, raphe fissures, and areolae were all found to be useful and important characters in distinguishing among species. Three distinct types of helictoglossae, referred to as linear, rolled tongue, and hoop shaped, are discussed. Taxa with linear or rolled-tongue-shaped helictoglossae also had T-shaped raphe fissures and circular hymen coverings. Taxa with hoop-shaped helictoglossae had teardrop-shaped raphe fissures and rectangular hymen coverings. K-cluster analysis was used to examine the distinction between F. krammeri and F. saxonica relative to the historical separation of F. rhomboides from F. saxonica.Key words: acidic ponds, Florida, Frustulia, Frustulia trochus, new species, Ocala National Forest.

Geographic variation in the pollen of Silene latifolia (S. alba, S. pratensis): a quantitative morphological analysis of population data

1984 ◽  
Vol 62 (6) ◽  
pp. 1259-1267 ◽  
Author(s):  
H. C. Prentice ◽  
O. Mastenbroek ◽  
W. Berendsen ◽  
P. Hogeweg
Keyword(s):  
Electron Micrographs ◽  
Pollen Morphology ◽  
Population Data ◽  
Morphological Characters ◽  
Silene Latifolia ◽  
Character State ◽  
Scanning Electron Micrographs ◽  
Components Analysis ◽  
Geographic Separation ◽  
Scanning Electron

There is a geographic separation of the two pollen morphs in European Silene latifolia, with the changeover zone running northwest – southeast from the Netherlands to Greece. Reticulate grains are characteristic of western populations and microechinate grains are characteristic of eastern populations. The present study is based on a sample of one pollen grain from each of the male individuals from each of 32 greenhouse-grown populations representing the distribution of S. latifolia across Europe. The 316 grains were scored for 11 morphological characters (61 character states) under the light microscope. Population character-state frequencies were analysed using cluster analysis and principal components analysis. The results support the geographic distribution of pollen morphs, but the populations with the typical eastern and western morphs are linked by a belt of populations with intermediate pollen morphology. Intermediate pollen is characteristic of populations in a zone from Belgium to Italy; the zone represents a region of relatively rapid morphological change and is coincident with a similar zone of change in seed and flavonoid characters in S. latifolia. Scanning electron micrographs from each population provided further information on the pollen morphology and complemented the light microscopical observations. The variation pattern is illustrated by scanning electron micrographs from selected populations.

scholarly journals STUDY OF THE CYTOLOGICAL AND MICRO-MORPHOLOGICAL CHARACTERISTICS OF SOME SPECIES OF THE GENUS EUPHORBIA L.BELONG TO EUPHORBIACEAE FAMILY , USING ELECTRON MICROSCOPE IN IRAQ

2020 ◽  
Vol 51 (5) ◽  
pp. 1394-1404
Author(s):  
Sulaiman & et al.
Keyword(s):  
Electron Microscope ◽  
Morphological Characteristics ◽  
Pollen Grains ◽  
Morphological Characters ◽  
Growing Seasons ◽  
Surface Configuration ◽  
Pollen Surface ◽  
Cytological Characteristics ◽  
Scanning Electron ◽  
Shape And Size

This study was aimed to investigate micro-morphological and cytological characteristics for sex species of Euphorbiaceae family in Baghdad during the two growing seasons 2018-2019 . The species are: Euphorbia granulate Forssk.,E.helioscopia L.,E. hirta L.,E. hypericifolia L., E. milli Des Moul .,E. puplus L. Which involved with morphological characters of pollen grains and seeds, as well the chromosomes number, and the study managed to count chromosome number for the above species sequentially:-n=11, n=21, n=9, n=16, n=14,18, n=7,8. The morphological characters of pollen grains surface has been studied by using scanning electron microscope (SEM), shape and size, polar and equatorial axes, spines length, dimensions of ora and colpi, and the ornamentations on pollen surface, and it has been observed that all the species are tri-zono-colporate, spinulose and spinate (echinated), and spinolophate fruite, and importance of the pollen grains in taxonomy. The study includes morphological characteristics of seeds  by using (SEM) In terms of size, shape, color, and appearance of the seed surface(configuration). It has been shown that the seeds are significantly different from species to another. Species help to isolate and classify, and through relying on these characteristics, classification limits could be set, whether at the level of species or genus within each family.

Some nivicolous species of Lamproderma and Meriderma from the Himalayan Mountains of northwestern India

Phytotaxa ◽  
2018 ◽  
Vol 373 (3) ◽  
pp. 221
Author(s):  
GABRIEL MORENO ◽  
ANGELA LÓPEZ VILLALBA ◽  
AURELIO CASTILLO ◽  
STEVEN L. STEPHENSON
Keyword(s):  
Electron Micrographs ◽  
Light Microscope ◽  
Morphological Characters ◽  
Scanning Electron Micrographs ◽  
Morphological Examination ◽  
Northwestern India ◽  
Himalayan Mountains ◽  
Scanning Electron

A detailed morphological examination of 12 specimens representing seven species in the genera Lamproderma and Meriderma collected from snowbank habitats in the Himalayan Mountains in northwestern India was carried out. Two of the specimens are described herein as Lamproderma spinisporum, a species new to science. In addition, the material from northwestern India is compared with other similar taxa belonging to the genus Lamproderma. Light microscope photographs and scanning electron micrographs of the most representative morphological characters are provided.

scholarly journals Pollen morphology of the native Rutaceae species from Argentina

2021 ◽  
Vol 9 (2) ◽  
pp. 282-292
Author(s):  
Silvina S. Garralla ◽  
Lilia R. Mautino
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pollen Morphology ◽  
Morphological Characteristics ◽  
Morphological Characters ◽  
Pollen Grain ◽  
Large Size ◽  
Scanning Electron ◽  
Shape And Size

The pollen morphology of 13 native taxa of the Rutaceae from Argentina was studied under optical and scanning electron microscopy to provide new data that would allow delimiting these taxa. The species considered were Balfourodendron riedelianum, Esenbeckia densiflora, E. febrifuga, E grandiflora, Helietta apiculata, Pilocarpus pennatifolius, Zanthoxylum caribaeum, Z. coco, Z. fagara, Z. petiolare, Z. rhoifolium, Z. riedelianum and Zanthoxylum rigidum ssp. hasslerianum. The general morphological characteristics of the pollen grain of these species are: radiosymmetric, isopolar; small, medium or large size; 3-colporate or 4-colporate; colpus with costa colpi; semitectate (reticulate, striate reticulate or striate). Sculpture, shape and size are the main characters that allow differentiating the studied taxa. Morphological characters among the species are discussed and a species key is presented.

The Alteration of the Pore Spaces in Sandstones

1973 ◽  
Vol 31 ◽  
pp. 210-211
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
The Other ◽  
Coarse Grained ◽  
Depositional Fabric ◽  
Soluble Components ◽  
Scanning Electron ◽  
Shape And Size

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.

scholarly journals A Kleptoparasitic Cecidomyiid and Other Flies Associated With Spiders

1980 ◽  
Vol 87 (3-4) ◽  
pp. 337-348 ◽  
Author(s):  
John Sivinski ◽  
Mark Stowe
Keyword(s):  
North America ◽  
Mature Male ◽  
North Central ◽  
Central Florida ◽  
Single Exception ◽  
Dominant Member

Spiders and their webs are predictable sources of insect cadavers. A small number of animals regularly exploit this resource, either as kleptoparasites or commensals, depending on whether symbionts compete for the same prey (see Robinson and Robinson, 1977, for more detailed terminology). Among the thieves are specialized spiders (citations in Vollrath 1979a, 1979b), mature male and juvenile spiders (Stowe 1978, citations in Nyffeler and Benz 1980), Hemiptera (Davis and Russell 1969), a hummingbird (takes webbing in addition to small insects, Young 1971), panorpid scorpion-flies (Thornhill 1975), Lepidoptera larvae (Robinson 1978), wasps (Jeanne 1972), damselflies (Vollrath 1977), and a handful of flies (reviews in Knab 1915; Bristowe 1931, 1941; Lindner 1937; Richards 1953; Robinson and Robinson 1977). Only a few of the reports on Diptera kleptoparasites originate from North America (McCook 1889, Frost 1913, Downes and Smith 1969). With a single exception (Downes and Smith 1969), all of the previously described kleptoparasitic flies belong to the Brachycera and Cyclorrhapha. We report here on a surprisingly diverse kleptoparasitic Diptera fauna in north central Florida with a cecidomyiid (Nematocera) as its dominant member.

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.

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