Description of Gomphothidium gen. nov., with light and scanning electron microscopy: A New Freshwater Monoraphid Diatom Genus from Asia

A new species of genus Campylodiscus is described, Campylodiscus sinensis sp. nov., from Dongtan, Chongming Island, Shanghai, China. It is a small species compared with other species in genus Campylodiscus, with two characteristic kidney-shaped bumps externally and pyramidal verrucae. Light and scanning electron microscopy characteristics of this taxon support its systematic placement in the genus Campylodiscus. This new species is compared with other small species in genus Campylodiscus from around the world.

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The diatom genus Gomphoneis Cleve (Bacillariophyceae) from Lake Baikal, Russia

Phytotaxa ◽

10.11646/phytotaxa.154.1.1 ◽

2013 ◽

Vol 154 (1) ◽

pp. 1 ◽

Cited By ~ 16

Author(s):

JOHN P. KOCIOLEK ◽

MAXIM S. KULIKOVSKIY ◽

CÜNEYT N. SOLAK

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Lake Baikal ◽

Western North America ◽

The West ◽

Nw China ◽

The World ◽

Diatom Genus ◽

Scanning Electron ◽

Species Flocks

We describe 22 new species of Gomphoneis, and report several previously described taxa, from historical and recently made collections from Lake Baikal, Russia. We use light microscopy to document all taxa, and scanning electron microscopy to illustrate several of the species from the lake. All of the species present in Lake Baikal are part of the Elegans subgroup of the genus. Despite previous reports, we could find no representatives of the Herculeana subgroup in Baikal. We provide comparisons between the taxa, and document variability in the features found in the species. Two groups within the Elegans subgroup are present; most have 4 (or more) stigmoids, while a minority of the species lack stigmoids. We suggest that the species in Lake Baikal have two origins; one from the West, where an arc of related species spans Mongolia, NW China to Macedonia, and the second from western North America. Radiation of the two groups has resulted in species flocks. The number of Gomphoneis species in Lake Baikal is the largest number of species of the genus anywhere in the world.

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The diatom genus Hantzschia (Bacillariophyta) in Xinjiang Province, China

Phytotaxa ◽

10.11646/phytotaxa.197.1.1 ◽

2015 ◽

Vol 197 (1) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

QINGMIN YOU ◽

JOHN PATRICK KOCIOLEK ◽

QUANXI WANG

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Small Populations ◽

Cosmopolitan Species ◽

Additional Information ◽

Diatom Genus ◽

Interesting Species ◽

Scanning Electron

Hantzschia species are uncommon in Xinjiang Province, usually found in small populations and found only in a few samples. However, the diversity in the region is relatively high, with 13 species and 1 variety being identified. Except for the cosmopolitan species H. amphioxys, H. abundans, H. virgata and H. distinctepunctata, most of the taxa in Hantzschia observed in this region have limited distributions, including H. vivacior, H. nitzschioides, H. compacta, H. barckhausenii, H. longa and H. vivax, as well as the species described herein as new. Four new species of Hantzschia are described: H. pseudobardii, H. sinensis, H. yili and H. subrobusta, a further two interesting species, H. vivacior and H. nitzschioides are documented with light and scanning electron microscopy. All species described are compared with other similar Hantzschia taxa from other localities or compared to holotype specimens. These data show a higher diversity of diatoms in Xinjiang Province than previously understood and provide additional information for understanding their biogeography.

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Two multi-stigmate Gomphonema species of Africa: Gomphonema kalahariense (nom. nov., stat. nov.) and Gomphonema chemeron (sp. nov.)

Phytotaxa ◽

10.11646/phytotaxa.436.3.5 ◽

2020 ◽

Vol 436 (3) ◽

pp. 270-282

Author(s):

JEFFERY R. STONE ◽

J. PATRICK KOCIOLEK ◽

KARLYN S. WESTOVER

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Quantitative Analysis ◽

Fossil Species ◽

New Name ◽

Diatom Genus ◽

Scanning Electron

The taxonomy and morphology of two taxa of the diatom genus Gomphonema with multiple stigmata from fossil localities in Africa are considered. Light and scanning electron microscopy as well as quantitative analysis of valve shape suggest two taxa are present in these collections. One of them, previously described as Gomphonema ventricosum var. africana, has 2–4 stigmata and conforms well with the original illustration of this taxon by Reichelt. However, this taxon does not appear to be closely related to G. ventricosum, and is a species in its own right, so a new name, G. kalahariense nom. nov., stat. nov. Jeff.R.Stone & Kociolek is proposed. This species is known from modern and fossil locations in Africa. A second species, Gomphonema chemeron Jeff.R.Stone, Westover & Kociolek sp. nov. is described from diatomite deposits of the Baringo Basin, Kenya, that are approximately 2.6 million years of age. This species, with 3–7 stigmata, has a distinctive shape and is easily distinguished from G. kalahariense. We compare these species with other multi-stigmate members of Gomphonema, including G. krammeri Reichardt, a fossil species described from Mexico and Cuba.

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New species of the genus Navicula Bory (Bacillariophyceae, Naviculaceae) from Lake Teletskoye

Phytotaxa ◽

10.11646/phytotaxa.404.4.5 ◽

2019 ◽

Vol 404 (4) ◽

pp. 163 ◽

Cited By ~ 2

Author(s):

DMITRY A. CHUDAEV

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

West Siberia ◽

Oligotrophic Lake ◽

Similar Species ◽

Lake Teletskoye ◽

Diatom Genus ◽

A New Species ◽

Scanning Electron

A new species from the diatom genus Navicula—N. teletskoyensis sp. nov. is described from mountain oligotrophic Lake Teletskoye (West Siberia). Morphology of the taxon was studied under light and scanning electron microscopy. New species is compared with morphologically similar species, it resembles N. pseudolanceolata, N. bourrellyivera, N. trivialis, N. oligotraphenta, N. hanseatica, N. melovskii, N. subconcentrica, N. johncarteri and N. vaneei.

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The diatom genus Gomphonema Ehrenberg in Lake Baikal. II. Revision of taxa from Gomphonema acuminatum and Gomphonema truncatum-capitatum complexes

Phytotaxa ◽

10.11646/phytotaxa.233.3.3 ◽

2015 ◽

Vol 233 (3) ◽

pp. 251 ◽

Cited By ~ 12

Author(s):

Maxim Sergeevich Kulikovskiy ◽

John Patrick Kociolek ◽

Cuneyt Nadir Solak ◽

Irina Kuznetsova

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Central Asia ◽

Lake Baikal ◽

Wide Distribution ◽

Species Complexes ◽

Diatom Genus ◽

Scanning Electron

We document the diversity of diatom taxa from the G. acuminatum and truncatum-capitatum species complexes in Lake Baikal using light and scanning electron microscopy. This investigation revealed four species new to Science, namely G. pseudacuminatum sp. nov., G. microlaticollum sp. nov., G. paracapitatum sp. nov., and G. microcapitatum sp. nov. In addition, we consider seven previously described species that are part of these ‘typical Gomphonema’ complexes. Some of the taxa treated here were previously observed from other regions, especially from Mongolia. These data show a wide distribution of species from these complexes in waterbodies of Central Asia, and confirm the presence of some cosmopolitan taxa within Lake Baikal.

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New Gomphoneis Cleve (Bacillariophyceae: Gomphonemataceae) species from Xinjiang Province, China

Phytotaxa ◽

10.11646/phytotaxa.103.1.1 ◽

2013 ◽

Vol 103 (1) ◽

pp. 1 ◽

Cited By ~ 9

Author(s):

QINGMIN YOU ◽

JOHN PATRICK KOCIOLEK ◽

QUANXI WANG

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Morphological Diversity ◽

Northwest China ◽

Western North America ◽

The Balkans ◽

Apical Pore ◽

Diatom Genus ◽

Scanning Electron

Eight new species of the diatom genus Gomphoneis Cleve from Xinjiang Province of northwest China are described. Observations were made using light and scanning electron microscopy, documenting the morphological diversity of the taxa, all of which are part of the G. elegans lineage, and lack isolated stigmoids. Five of the new species (Gomphoneis pseudosubtiloides, G. xinjiangiana, G. basiorobusta, G. stoermeri and G. distorta) have porelli in the apical pore fields organized into two rows, similar to the organization of the striae areolae. Three species (G. subtiloides, G. qii and G. rostratoides) have porelli of similar size, shape and organization to the areolae, supporting the interpretation that the apical pore fields in this group are condensed striae. The species from Xinjiang Province appear morphologically similar to taxa from the Balkans of Europe, and may be part of a wide continuum of distribution between that region and western North America. This is only the second report on Gomphoneis from Xinjiang Province. A number of taxa similar to the new species described herein, and related to Gomphoneis olivacea, are also considered. As a consequence, the total number of Gomphoneis taxa from China is greater than previously recognized.

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Prvi nalaz proizvodnje domoične kiseline u kulturama vrste Pseudo-nitzschia calliantha iz srednjeg Jadrana

Acta Adriatica ◽

10.32582/aa.61.2.2 ◽

2020 ◽

Vol 61 (2) ◽

pp. 135-144

Author(s):

Jasna Arapov ◽

Ivana Ujević ◽

Živana Ninčević Gladan ◽

Ana Bakrač ◽

Mia Bužančić ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Domoic Acid ◽

Adriatic Sea ◽

Cell Abundance ◽

Diatom Genus ◽

Seawater Samples ◽

Scanning Electron

In this study, three isolates of the potentially toxic diatom genus Pseudo-nitzschia were analysed for morphological and toxicological features. Cultures of Pseudo-nitzschia were established from seawater samples collected from the southern part of the Velebit Channel (central Adriatic Sea) during February 2019. All culture isolates were identified by scanning electron microscopy (SEM) as Pseudo-nitzschia calliantha. Domoic acid (DA) production was confirmed in all isolates analysed. The highest concentrations of cellular DA were found in early culture stages, with the lowest cell abundance, for all P. calliantha isolates. This study is the first to report DA production by P.calliantha isolated from the Adriatic Sea.

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The genus Luticola (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean) with the description of two new species

European Journal of Taxonomy ◽

10.5852/ejt.2017.387 ◽

2017 ◽

Cited By ~ 1

Author(s):

Barbora Chattová ◽

Marc Lebouvier ◽

Myriam De Haan ◽

Bart Van de Vijver

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Indian Ocean ◽

Saint Paul ◽

Southern Indian Ocean ◽

Two New Species ◽

Diatom Genus ◽

Volcanic Islands ◽

Scanning Electron

Five species of the terrestrial diatom genus Luticola D.G.Mann were found during a taxonomic survey of two small volcanic islands, Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean). Apart from the two already known Luticola species L. beyensii Van de Vijver et al. and L. subcrozetensis Van de Vijver et al., two new species are described: L. ivetana Chattová & Van de Vijver sp. nov. and L. vancampiana Chattová & Van de Vijver sp. nov. Finally, one, up to now unknown, Luticola species is briefly discussed and illustrated. Detailed morphological descriptions of these taxa are provided based on both light and scanning electron microscopy observations. Morphological features of the new species are compared to morphologically similar taxa, and notes on their ecology and biogeography are added.

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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