scholarly journals On the identity of the rare Fragilaria subconstricta (Fragilariaceae), with Fragilaria species forming ribbon-like colonies shortly reconsidered

2019 ◽  
Vol 152 (2) ◽  
pp. 327-339 ◽  
Author(s):  
David Heudre ◽  
Carlos E. Wetzel ◽  
Laura Moreau ◽  
Bart Van de Vijver ◽  
Luc Ector
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Rare Species ◽  
Central Area ◽  
Similar Species ◽  
New Synonyms ◽  
Freshwater Pond ◽  
Large Numbers ◽  
Northeastern France ◽  
Scanning Electron

Background and aims – During phytoplankton surveys of a freshwater pond in Northeastern France, Fragilaria subconstricta (Bacillariophyceae) was observed. This rare diatom was present in large numbers in several plankton samples from Lachaussée Pond in the French Grand Est region. Methods – The morphology of Fragilaria subconstricta was examined in detail using light and scanning electron microscopy. Its identity is discussed and it is compared to the morphologically most similar species, especially Fragilaria capucina, F. mesolepta Rabenhorst, F. neointermedia and F. tenuistriata. Key results – Fragilaria subconstricta produces ribbon-like colonies and has narrow linear-lanceolate valves with slightly rostrate ends. The central area is rectangular, usually small or even absent. Spatulate linking spines are present all along the valve margins and a single rimoportula is located near one apex at the valve face-mantle junction. An amended diagnosis and new synonyms are proposed for this species. Additionally, the type material of Fragilaria mesolepta and a population of the very rare species Fragilaria capucina have been investigated and illustrated. Conclusions – Fragilaria subconstricta and F. tenuistriata are synonyms. Fragilaria capucina s. str. is a rare species in Europe, and the majority of records for this species should be considered part of the Fragilaria capucina “Sippenkomplex” sensu Krammer & Lange-Bertalot (1991).

Oricymba tianmuensis sp. nov., a new cymbelloid species (Bacillariophyceae) from Tianmu Mountain in Zhejiang Province, China

Phytotaxa ◽  
2015 ◽  
Vol 236 (3) ◽  
pp. 257 ◽  
Author(s):  
Wei Zhang ◽  
Yan Ling Li ◽  
J Patrick Kociolek ◽  
Rui Lei Zhang ◽  
Li Qing Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Central Area ◽  
Ventral Side ◽  
Zhejiang Province ◽  
Similar Species ◽  
The West ◽  
West Region ◽  
Freshwater Diatoms ◽  
Scanning Electron

During a survey of freshwater diatoms from streams in the west region of the Tianmu Mountains, Zhejiang Province, China, a new Oricymba species, Oricymba tianmuensis sp. nov. has been recorded. A detailed morphology description of O. tianmuensis is presented, based on light and scanning electron microscopy. Oricymba tianmuensis sp. nov. is characterized by a ridge along the valve face typical of the genus, as well as a linear-lanceolate, symmetrical or slightly dorsiventral outline with a gibbous central portion gradually tapering or nearly paralleling towards the bluntly cuneate poles, a distinct rhombic-lanceolate asymmetric central area with a distinct stigma on the ventral side of the central nodule, a slightly lateral raphe with widened proximal endings and strongly deflected distal endings, and weakly radiate striae. Morphological features of the taxon are compared with similar species, and the biogeography of the genus is summarized.

To morphology, ecology and distribution of rare species Sellaphora hustedtii (Krasske) Lange-Bertalot et Werum (Bacillariophyta) from waterbodies of the Gydan Peninsula

2014 ◽  
Vol 48 ◽  
pp. 57-65 ◽  
Author(s):  
S. I. Genkal ◽  
M. I. Jarushina
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
River Basin ◽  
Rare Species ◽  
Western Siberia ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Diagnostic Features ◽  
Scanning Electron Microscopy Study ◽  
Scanning Electron

A rare species Sellaphora hustedtii, which is also new for the flora of Russia, has been found in waterbodies of the Messoyakha River basin (south-western part of the Gydan Peninsula, Western Siberia). The scanning electron microscopy study revealed variability of the main quantitative and qualitative diagnostic features of the species (length and width of the valve, number of striae and areolae in 10 μm, shape of the valve and structure of the raphe). New data on the ecology and distribution of the species allowed us to specify its diagnosis.

Sellaphora labernardierei (Sellaphoraceae, Bacillariophyta), a new epilithic species from French spring and four new combinations within the genus Sellaphora

Phytotaxa ◽  
2016 ◽  
Vol 260 (3) ◽  
pp. 235 ◽  
Author(s):  
AUDE BEAUGER ◽  
CARLOS E. WETZEL ◽  
OLIVIER VOLDOIRE ◽  
ALEXANDRE GARREAU ◽  
LUC ECTOR
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Central Area ◽  
Mineral Waters ◽  
New Combinations ◽  
French Massif Central ◽  
Small Species ◽  
Massif Central ◽  
Floristic Survey ◽  
Scanning Electron

During a floristic survey of freshwater springs in the French Massif Central region, a new Sellaphora species (Bacillariophyceae) was found and is hereby described: Sellaphora labernardierei sp. nov. This new small species, with linear to linear-elliptical valves, slightly inflated in the middle, is formally described using light and scanning electron microscopy. The species has a single H-shaped chloroplast and striae usually biseriate tending to be uniseriate near the centre of the valve. The valve dimensions, the valve, pole and central area shapes, and the striae density and pattern allow their separation from similar taxa belonging to the genera Eolimna, Naviculadicta and Sellaphora. The ecological preferences of Sellaphora labernardierei are mineral waters with high nitrate concentrations. The examination of similar taxa belonging to the genera Eolimna and Naviculadicta and their characteristics lead to propose four new combinations of Sellaphora species.

Two new Stauroneis species (Bacillariophyta, Stauroneidaceae) from midwestern karstic Brazilian formations

Phytotaxa ◽  
2018 ◽  
Vol 358 (3) ◽  
pp. 265 ◽  
Author(s):  
EDUARDO A. TUSSET ◽  
PRISCILA I. TREMARIN ◽  
THELMA A.V. LUDWIG
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Similar Species ◽  
Scanning Electron ◽  
Bow Tie

The morphology of three Stauroneis species from midwestern karstic Brazilian formations was illustrated under light and electron microscopy. Two new Stauroneis are described and compared with similar species in the genus. Stauroneis cavalcantei Tremarin, Tusset & T. Ludwig is characterized by lanceolate valves with subtly protracted apices, and S. karstica Tusset, Tremarin & T. Ludwig by rhombic-lanceolate valves with attenuate to acutely-rounded apices, reduced pseudosepta, bow-tie-shaped stauros, and areolae depressed along prominent longitudinal-oriented apical ribs. Stauroneis alabamae is a scarcely known species and unprecedented scanning electron microscopy illustrations are provided.

Four new species of monoraphid diatoms from Western Sichuan Plateau in China

Phytotaxa ◽  
2021 ◽  
Vol 479 (3) ◽  
pp. 257-274
Author(s):  
Q.M. YOU ◽  
K. ZHAO ◽  
Y.L. WANG ◽  
P. YU ◽  
J.P. KOCIOLEK ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
New Species ◽  
Central Area ◽  
Morphological Characteristics ◽  
Similar Species ◽  
Small Species ◽  
Western Sichuan ◽  
The Relationship ◽  
Scanning Electron ◽  
Apical Axis

Four new monoraphid diatoms are examined and described from a high-altitude (> 3000 m) region of western Sichuan, China.  The descriptions are based on light and scanning electron microscopy observations, and the four new species are compared with similar taxa worldwide.  Achnanthidium sichuanense sp. nov. has small, lanceolate-elliptical valves, with rounded apices. The outline and central area differentiate it from similar species.  The unique characteristic of Eucocconeis undulatum sp. nov. is that it has valves that are undulate along the apical axis, forming an “H”-shaped area on both raphe and rapheless valves as seen in light microscope (LM).  Platessa mugecuonesis sp. nov. and Platessa lanceolata sp. nov. are two small species, whose valve outlines and central areas make them different from other species in this genus.  A. sichuanense sp. nov. and E. undulatum sp. nov. are discussed in terms of the relationship between “Achnanthidium & Psammothidium” and “Eucocconeis & Psammothidium”, as these genera are difficult to separate according to morphological characteristics.

The genus Navicula (Bacillariophyceae, Naviculaceae) from the valley of the Adegoy River (Krasnodar Territory, Russia) and description of two new species

Phytotaxa ◽  
2021 ◽  
Vol 494 (2) ◽  
pp. 208-218
Author(s):  
DMITRY CHUDAEV ◽  
INGRID JÜTTNER ◽  
ZLATKO LEVKOV
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
River Valley ◽  
Similar Species ◽  
Taxonomic Study ◽  
The Caucasus ◽  
Caucasus Region ◽  
Two New Species ◽  
Scanning Electron

This is the first detailed taxonomic study of the genus Navicula in the Krasnodar Territory of the Caucasus region, Russia. During the study of the genus in waterbodies of the Adegoy River valley 15 taxa were recorded. Two species, N. adegoyensis sp. nov. and N. pseudocryptofallax sp. nov., are described as new to science. Their morphology is studied by light and scanning electron microscopy, and comparisons with morphologically similar species are provided. The use of the name N. avenacea for N. lanceolata sensu auct. is discussed. Navicula diversity was higher in the Adegoy River than in pools elsewhere in the river valley.

Fragilaria irregularis sp. nov. a new araphid species (Fragilariaceae, Bacillariophyta) from the River Adegoy, Krasnodar Territory, Russia

Phytotaxa ◽  
2021 ◽  
Vol 508 (2) ◽  
Author(s):  
DMITRY CHUDAEV ◽  
INGRID JÜTTNER ◽  
BART VAN DE VIJVER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Similar Species ◽  
New Taxon ◽  
Weakly Convex ◽  
Diatom Flora ◽  
A New Species ◽  
Scanning Electron

During a survey of the diatom flora of the Adegoy River (Krasnodar Territory, Russia), an unknown Fragilaria species (Bacillariophyta) was found that could not be identified using the currently available literature and here we describe it as a new species. The morphology of Fragilaria irregularis sp. nov. was studied using light and scanning electron microscopy and compared to similar species including Fragilaria deformis, F. rinoi, F. septentrionalis and Fragilariforma bicapitata. It differed from these taxa in several characters. Most observed valves showed an irregular striation pattern, a feature not observed in other species. Other important differences include valve outline (linear with parallel margins) and stria density (7–14 in 10 µm, lower compared to all other species). The new taxon has a linear valve outline with parallel to weakly convex margins, subcapitate apices and a very irregular, coarse striation pattern.

A new species of Neidiomorpha (Bacillariophyceae) from Dianshan Lake in Shanghai, China

Phytotaxa ◽  
2019 ◽  
Vol 423 (2) ◽  
pp. 99-104
Author(s):  
FEN LUO ◽  
QI YANG ◽  
KAIJUAN GUO ◽  
TENGTENG LIU ◽  
QUANXI WANG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Central Area ◽  
Diatom Species ◽  
Dianshan Lake ◽  
A New Species ◽  
Scanning Electron

A new diatom species, Neidiomorpha dianshaniana sp. nov., found in Dianshan Lake in Shanghai, China, is described herein. The morphology of N. dianshaniana has been documented by light and scanning electron microscopy. Neidiomorpha dianshaniana valves are elliptical in outline with rostrate apices. Raphe is almost straight and filiform. The axial area is narrow and linear. The central area is small, round to transversely elliptical or irregular. Striae are slightly radiate and almost parallel near the apices. Puncta are arranged in undulating longitudinal rows. Neidiomorpha dianshaniana’s most visible feature is its lack of central constriction, in which respect it differs from the three other species in the genus Neidiomorpha.

Four new Luticola taxa (Bacillariophyta) from Maritime Antarctica 

Phytotaxa ◽  
2014 ◽  
Vol 170 (3) ◽  
pp. 155 ◽  
Author(s):  
RALITSA ZIDAROVA ◽  
ZLATKO LEVKOV ◽  
BART VAN DE VIJVER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Taxa ◽  
Similar Species ◽  
The South ◽  
Maritime Antarctica ◽  
World Data ◽  
The World ◽  
Scanning Electron

The paper describes four new Luticola taxa from the South Shetland Archipelago, Antarctica:  Luticola neglecta sp. nov., L. bogaertsiana sp. nov., L. contii sp. nov. and L. olegsakharovii sp. nov. All new taxa are studied using both light and scanning electron microscopy and compared to other morphologically similar species from (sub-)Antarctica and elsewhere in the world. Data on their ecology and biogeography are added. 

Two new centric diatoms (Bacillariophyta) from the sub-Antarctic region

Phytotaxa ◽  
2019 ◽  
Vol 394 (1) ◽  
pp. 50 ◽  
Author(s):  
BART VAN DE VIJVER ◽  
VÁCLAV HOUK
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Central Area ◽  
Soil Samples ◽  
Antarctic Region ◽  
Diatom Flora ◽  
Main Island ◽  
Centric Diatoms ◽  
Heard Island ◽  
Scanning Electron

During a survey of the limno-terrestrial diatom flora of the sub-Antarctic region, two unknown melosiroid diatom taxa were observed in several shaded, damp cave (moss and soil) samples from Heard Island and Ile de la Possession, the main island of the Crozet Archipelago. Comparison with already known species from the genus Melosira and the recently described genera Arcanodiscus, Angusticopula and Ferocia, resulted in the description of both new taxa based on detailed light and scanning electron microscopy. A first species was described as Ferocia subantarctica sp. nov. and can be distinguished based on its numerous, narrow girdle bands, relatively weakly domed valves, a limited number of well-developed spines and a rather large, hyaline central area. The second species, Arcanodiscus desmetianus Van de Vijver sp. nov., can be recognized based on its solitary frustules, a series of parallel ridges surrounding the mantle and a hyaline central area that is only less than 50% of the total valve diameter. Both taxa are morphologically and ecologically characterized and compared with all known melosiroid taxa worldwide.

Sign in / Sign up

Export Citation Format

Share Document