Nitzschia anatoliensis sp. nov., a cryptic diatom species from the highly alkaline Van Lake (Turkey)

In this article we describe Nitzschia anatoliensis Górecka, Gastineau & Solak sp. nov., an example of a diatom species inhabiting extreme habitats. The new species has been isolated and successfully grown from the highly alkaline Van Lake in East Turkey. The description is based on morphology (light and scanning electron microscopy), the sequencing of its organellar genomes and several molecular phylogenies. This species could easily be overlooked because of its extreme similarity to Nitzschia aurariae but molecular phylogenies indicate that they are only distantly related. Furthermore, molecular data suggest that N. anatoliensis may occur in several alkaline lakes of Asia Minor and Siberia, but was previously misidentified as Nitzschia communis. It also revealed the very close genetic proximity between N. anatoliensis and the endosymbiont of the dinotom Kryptoperidinium foliaceum, providing additional clues on what might have been the original species of diatoms to enter symbiosis.

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Analysis of the type material of Achnanthes minutissima var. macrocephala (Bacillariophyta) and description of two new small capitate Achnanthidium species from Europe and the Himalaya

Plant Ecology and Evolution ◽

10.5091/plecevo.2019.1628 ◽

2019 ◽

Vol 152 (2) ◽

pp. 340-350

Author(s):

Carlos E. Wetzel ◽

Ingrid Jüttner ◽

Smriti Gurung ◽

Luc Ector

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Benthic Diatom ◽

Original Material ◽

Diatom Species ◽

The World ◽

Freshwater Habitats ◽

The Himalaya ◽

Scanning Electron ◽

Achnanthes Minutissima

Background and aims – Two unknown benthic diatom species belonging to the genus Achnanthidium Kütz., and found in French and Nepalese freshwater habitats, were investigated. Both species are here described as new and compared with the original material of Achnanthes minutissima var. macrocephala Hust. [≡ Achnanthidium macrocephalum (Hust.) Round & Bukht.] from Indonesia. Methods – The morphology of three small and capitate Achnanthidium species was investigated using light microscopy (LM) and scanning electron microscopy (SEM). Key results – Achnanthidium coxianum sp. nov. (from the Himalaya) belongs to the group of species with hooked terminal raphe endings, while Achnanthidium peetersianum sp. nov. (from France) has variable terminal raphe endings which are usually slightly bent. Achnanthidium macrocephalum is a much rarer species and illustrations concerning its identity in the literature do not conform to the type studied here. Conclusions – The three species are similar in LM but clearly distinct in SEM. The shape of the areolae and terminal raphe endings separate the species. Achnanthidium macrocephalum has often been misidentified in studies from many areas of the world. It is similar to the new species in valve outline and in its small dimensions.

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

Phytotaxa ◽

10.11646/phytotaxa.423.2.6 ◽

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.

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Cocconeis kurakakea, a new diatom species from Nukutavake (Tuamotu Archipelago, South Pacific): description and comparison with C. diruptoides and C. pseudodiruptoides

Phytotaxa ◽

10.11646/phytotaxa.349.2.2 ◽

2018 ◽

Vol 349 (2) ◽

pp. 115 ◽

Cited By ~ 1

Author(s):

CATHERINE RIAUX-GOBIN ◽

ANDRZEJ WITKOWSKI ◽

RICHARD W. JORDAN ◽

VALERIANO PARRAVICINI ◽

SERGE PLANES

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

South Pacific ◽

Benthic Diatom ◽

New Taxon ◽

Diatom Species ◽

The South ◽

Standard Methods ◽

Tuamotu Archipelago ◽

Scanning Electron

During the ‘Tara Pacific 2016–2018 Expedition’, marine benthic diatom samples were collected from several Tuamotu atolls in the South Pacific. Preparation and examination of these samples were conducted following standard methods including light and scanning electron microscopy. A small-celled taxon from the genus Cocconeis Ehrenb. (Bacillariophyceae) is described from the Nukutavake reef, and compared to several other taxa for which the definition is not always clear (e.g., Cocconeis diruptoides Hust. and Cocconeis pseudodiruptoides Foged). The new taxon is present only on one of the investigated Tuamotu atolls, possibly indicating local endemism.

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Navicula gogorevii—a new, large-celled diatom species from Vietnam (Southeast Asia)

Phytotaxa ◽

10.11646/phytotaxa.428.1.6 ◽

2020 ◽

Vol 428 (1) ◽

pp. 60-66

Author(s):

MAXIM KULIKOVSKIY ◽

DMITRY CHUDAEV ◽

ANTON GLUSHCHENKO ◽

IRINA KUZNETSOVA ◽

ZINAIDA KRIVOVA ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Characteristic Feature ◽

Southeast Asia ◽

Sensu Stricto ◽

Diatom Species ◽

Scanning Electron

We describe a new member from the genus Navicula Bory sensu stricto using light and scanning electron microscopy. The new species was found in Vietnam, and is a large-celled species with longitudinal grooves present on the valve exterior. Taxa sharing this feature are known from the genus Navicula, as well as the genera Haslea Simonsen, Craticula Grunow, Gyrosigma Hassall and Proschkinia Karajeva. The new species from Vietnam is compared with other, similar taxa of Navicula, and comments are presented about the systematics and biogeography of the group of Navicula species with this characteristic feature.

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Brachysira aristidesii sp. nov. (Bacillariophyceae, Brachysiraceae): a new species from oligotrophic and mesotrophic tropical reservoirs in southeastern Brazil

Phytotaxa ◽

10.11646/phytotaxa.456.1.8 ◽

2020 ◽

Vol 456 (1) ◽

pp. 105-113

Author(s):

STÉFANO ZORZAL-ALMEIDA ◽

ELAINE C. RODRIGUES BARTOZEK ◽

EDUARDO A. MORALES ◽

DENISE C. BICUDO

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

High Water ◽

Southeastern Brazil ◽

Diatom Species ◽

Tropical Reservoirs ◽

A New Species ◽

Piracicaba River ◽

Scanning Electron

A new diatom species, Brachysira aristidesii sp. nov., is described from three oligotrophic and mesotrophic reservoirs in Piracicaba River basin, State of São Paulo, Brazil. Descriptions are based on light and scanning electron microscopy. The new species is mainly characterized by rhombic-lanceolate valves with strongly capitated ends, filiform and straight raphe, narrow and linear axial area, slightly radiate striae and transapically elongated areolae. It is compared to Brachysira microcephala, B. silvicola, B. vitrea, B. neoexilis and Nupela brachysiroides. Our findings suggest that Brachysira aristidesii is a species mainly associated to high water transparency, low to moderate conductivity, slightly acidic and low nutrient environments.

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Planothidium sheathii, a new monoraphid diatom species from rivers in California, USA

Phytotaxa ◽

10.11646/phytotaxa.393.2.4 ◽

2019 ◽

Vol 393 (2) ◽

pp. 131 ◽

Cited By ~ 3

Author(s):

ROSALINA STANCHEVA

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Morphological Features ◽

Diatom Species ◽

Unique Combination ◽

Valve Morphology ◽

Valve Margin ◽

A New Species ◽

Scanning Electron

Planothidium sheathii sp. nov., a new species from rivers in California, USA, is described based on light and scanning electron microscopy. P. sheathii has broadly lanceolate to elliptic valves with obtusely rounded apices and a unique combination of morphological features, as follows: 1) cavum with broad hood aperture that flares out at the valve margin with open borders fused with the neighboring virgae on SV, 2) multiseriate striae, composed of five to six rows of same sized areolae on both valves, interrupted at valve mantle junction, and 3) areolae groups on valve mantle, with rounded areolae on RV, and rounded and elongated areolae on SV. Valve morphology of P. sheathii is discussed in comparison with similar freshwater taxa, from which the new species is clearly distinct.

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Sichuaniella deqinensis sp. nov., a new diatom species (Bacillariophyceae) from a high altitude lake in the Hengduan Mountains, SW China

Phytotaxa ◽

10.11646/phytotaxa.449.1.8 ◽

2020 ◽

Vol 449 (1) ◽

pp. 83-89

Author(s):

HAN WU ◽

TENG-ZHONG ZHANG ◽

YAN-LING LI ◽

DITMAR METZELTIN ◽

HORST LANGE-BERTALOT ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

High Altitude ◽

Southwest China ◽

Hengduan Mountains ◽

Diatom Species ◽

Small Lake ◽

High Altitude Lake ◽

Scanning Electron

A second species of the genus Sichuaniella Yan L. Li, Lange-Bertalot & Metzeltin 2013 from China is described as new to science. The new species, S. dequinensis spec. nov., is documented with light and scanning electron microscopy. This new species is distinguished from the only other species of the genus, S. lacustris, by having a higher density of more strongly radiate alveoli between broader interstriae, and a broader axial area. The new species is known only from a small lake in the Hengduan Mountains region of southwest China.

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A new marine epiphytic diatom species, Halamphora yundangensis sp. nov. (Bacillariophyceae), from Yundang Lake, Southeast coast of China

Phytotaxa ◽

10.11646/phytotaxa.450.2.6 ◽

2020 ◽

Vol 450 (2) ◽

pp. 209-218

Author(s):

WEIWEI WU ◽

HUINA LIN ◽

VISHAL PATIL ◽

JOHN PATRICK KOCIOLEK ◽

LIN SUN ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Similar Species ◽

Dorsal Margin ◽

Ventral Margin ◽

Diatom Species ◽

Green Seaweed ◽

A New Species ◽

Scanning Electron

Halamphora yundangensis sp. nov. is described as a new species epiphytic on the green seaweed Ulva lactuca, from Yundang Lake, Fujian Province, China. Morphological details of the new species with respect to shape, size and valve ultrastructure are presented, with observations based on light microscopy (LM) and scanning electron microscopy (SEM). The main features of Halamphora yundangensis are dorsiventral, semi-lanceolate valves with convex dorsal margin and straight ventral margin, as well as valve ends distinctly protracted and capitate. Externally, a prominent marginal ridge forming the image of a broad hyaline area is present. Internally, dorsal striae are regularly biseriate, and a row of areolae lies along raphe. The new species is compared with similar species in both Amphora and Halamphora.

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A new Planothidium species (Achnanthidiaceae, Bacillariophyceae) from Xingu Ria, Amazon River basin, Brazil

Phytotaxa ◽

10.11646/phytotaxa.477.2.4 ◽

2020 ◽

Vol 477 (2) ◽

pp. 194-204

Author(s):

KRYSNA S. MORAIS ◽

LÍVIA F. COSTA ◽

CARLOS E. DE M. BICUDO ◽

LUC ECTOR ◽

CARLOS E. WETZEL

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

River Basin ◽

Brazilian Amazon ◽

Diatom Species ◽

Amazon River Basin ◽

Sediment Samples ◽

Xingu River ◽

Scanning Electron

A new Planothidium species was found in sediment samples (~4,000 yr BP) from the Xingu Ria (Xingu River), Brazilian Amazon. The new species morphology was analyzed using light and scanning electron microscopy. Planothidium xinguense sp. nov., is mainly characterized by its elliptical, slightly asymmetrical valves, with strongly marked short rostrate ends in the small specimens, while long and strongly rostrate apices are observable in the larger valves. The taxon belongs to the group of species bearing a cavum on the rapheless valves around the name “Planothidium rostratum sensu lato”. Morphology and ecology of the new species is compared with that of morphologically related taxa. Information of core chronology and the co-occurrence of other diatom species in the sample is also provided.

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Gomphonema bicepiformis sp. nov., a new diatom species (Bacillariophyta) from a stream in Zhejiang, China

Phytotaxa ◽

10.11646/phytotaxa.375.4.3 ◽

2018 ◽

Vol 375 (4) ◽

pp. 274 ◽

Cited By ~ 2

Author(s):

WEI ZHANG ◽

GUANGXIA SHANG ◽

JHONE PATRICK KOCIOLEK ◽

LIQING WANG ◽

HONGXIN TAN

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

New Species ◽

Central Region ◽

Zhejiang Province ◽

Clean Water ◽

Diatom Species ◽

Freshwater Diatoms ◽

Scanning Electron

During a survey of freshwater diatoms from Shibadukeng stream in the Xianju County, Zhejiang Province, China, a new gomphonemoid species, Gomphonema bicepiformis sp. nov. has been recorded. The new species is diagnosed from all others in the genus based on morphology as observed with both light and scanning electron microscopy. Valves of Gomphonema bicepiformis are lanceolate with a gibbous central region. The headpole is broadly rounded, clearly capitate and the footpole is also broadly rounded, capitate. The axial area is wide, lanceolate-rhombic, broad at mid-valve, reaching 3/4 of the total breadth. There are circular to irregularly-shaped depressions in the axial area on the exterior of the valve surface often appearing as light spots in LM. The new species was compared with G. biceps, G. obstipum, G. manubrium, G. pyrenaicum, G. guayabense and G. nipponica, all of which resemble Gomphonema bicepiformis in outline, but differ from the new species in specific details of size, striae density, and extent of the axial area. This species occurs in relatively low conductivity and clean water in Zhejiang, China.

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