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

Phytotaxa ◽  
2020 ◽  
Vol 456 (1) ◽  
pp. 105-113
Author(s):  
STÉFANO ZORZAL-ALMEIDA ◽  
ELAINE C. RODRIGUES BARTOZEK ◽  
EDUARDO A. MORALES ◽  
DENISE C. BICUDO

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.

Phytotaxa ◽  
2019 ◽  
Vol 423 (2) ◽  
pp. 99-104
Author(s):  
FEN LUO ◽  
QI YANG ◽  
KAIJUAN GUO ◽  
TENGTENG LIU ◽  
QUANXI WANG ◽  
...  

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.


Phytotaxa ◽  
2019 ◽  
Vol 393 (2) ◽  
pp. 131 ◽  
Author(s):  
ROSALINA STANCHEVA

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.


Phytotaxa ◽  
2020 ◽  
Vol 450 (2) ◽  
pp. 209-218
Author(s):  
WEIWEI WU ◽  
HUINA LIN ◽  
VISHAL PATIL ◽  
JOHN PATRICK KOCIOLEK ◽  
LIN SUN ◽  
...  

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.


Phytotaxa ◽  
2021 ◽  
Vol 482 (1) ◽  
pp. 55-64
Author(s):  
YUN ZHANG ◽  
MENGNA LIAO ◽  
YAN-LING LI ◽  
FENG-QIN CHANG ◽  
JOHN PATRICK KOCIOLEK

This paper describes a new species of Cymbella from an alpine lake in the Hengduan Mountains, southwestern China. The detailed morphological description of the new species, named Cymbella xiaojinensis sp. nov. is presented, based on light and scanning electron microscopy. The main features of C. xiaojinensis are characterized by strongly dorsiventral, triangular valves with a strongly reverse-lateral raphe system positioned near the proximal ends and an asymmetrical, larger central area, occupying approximately 1/2 of the width with the valve. Most morphological characteristics of the new species are similar to C. shudunensis, C. terrafuegiana, C. pamirensis, and C. gravida, but differ in details of size, valve shape, striae density, central area, and number of stigmata.


Phytotaxa ◽  
2021 ◽  
Vol 509 (2) ◽  
Author(s):  
STANEK-TARKOWSKA JADWIGA ◽  
CZYŻ EWA ANTONINA ◽  
RYBAK MATEUSZ

A new Microcostatus species was found during a study focusing on diatoms present on soils and among terrestrial mosses. Unlike most known European species of this genus, it has easily distinguishable striae under the light microscope and a distinct central area. Additionally, the newly described species shows lack of conopeum and pseudoconopeum. A detailed morphological characterisation using light and scanning electron microscopy of a new species from the genus Microcostatus and comparison to the most similar taxa are given.


2018 ◽  
Vol 52 (2) ◽  
pp. 379-385 ◽  
Author(s):  
S. L. Stephenson ◽  
Yu. K. Novozhilov ◽  
P. Wellman

A new species of Cribraria, described herein as C. bicolor, appeared in moist chamber cultures on samples of the bark of Eucalyptus sp. collected at two localities in Australia. The morphology of representative specimens was examined by light and scanning electron microscopy, and micrographs of relevant morphological details of sporocarps and spores are provided. The species has a number of distinct and unique morphological features, including a glossy bright-violet globose sporotheca and a two-colored long stalk which is bright-red over the lower one-third and light yellow or lemon-yellow over the upper two-thirds. The combination of these characteristics as well as a shallow calyculus which is dark-violet when viewed under a dissecting microscope and bright red in transmitted light when mounted in lactophenol makes C. bicolor a well-defined morphospecies when compared to all other species of Cribraria. The stability of the taxonomic characters of the species was confirmed by an examination of a number of specimens.


Phytotaxa ◽  
2021 ◽  
Vol 480 (3) ◽  
pp. 284-290
Author(s):  
QI LIU ◽  
JIAJIA LI ◽  
QUANXI WANG ◽  
JOHN PATRICK KOCIOLEK Patrick Kociolek ◽  
Shulian Xie

A new species, Encyonema oblonga Liu & Xie, is collected during a survey of the freshwater diatom flora of Manghe River, Shanxi, China. The valves of this new species are oblong with rounded apices and have the features typical of Encyonema, including complex areolae. We compare the new species with the most similar taxa, E. leei, E. leei var. sinensis and E. appalachianum and consider that  E. leei var. sinensis is the valid name.  The morphology of E. oblonga is documented with light and scanning electron microscopy.


Phytotaxa ◽  
2019 ◽  
Vol 388 (2) ◽  
pp. 155 ◽  
Author(s):  
BART VAN DE VIJVER ◽  
SANDRA WILFERT ◽  
VACLAV HOUK ◽  
DAVID M. JOHN

During a diatom survey of some samples from Ascension Island, a remote island located in the southern Atlantic Ocean, an unknown melosiroid diatom species was studied using both light and scanning electron microscopy. It proved to be a new species described as Angusticopula rowlingiana sp. nov. and characterized by a large number of narrow copulae in the girdle, a marginal ring of small granules, very small pores covering the entire valve face and occasionally having internal valves.                The new species is compared with all Angusticopula species known worldwide and with several Melosira species showing a similar combination of characters. Short notes on its ecology are included.


Phytotaxa ◽  
2021 ◽  
Vol 496 (2) ◽  
pp. 121-133
Author(s):  
HRISTINA KOCHOSKA ◽  
DUŠICA ZAOVA ◽  
ANASTASIJA VIDESKA ◽  
DANIJELA MITIC-KOPANJA ◽  
HRISTINA NAUMOVSKA ◽  
...  

Lowland intermittent ponds, although biologically important, are poorly studied water habitats. During the analyses of the material taken from lowland pond in Pelagonia Valley, and Vitachevo, Republic of North Macedonia, the diatom Sellaphora pelagonica sp. nov. was recorded and described based on light and scanning electron microscopy. The species is characterized by a strictly linear valve outline with parallel to slightly concave margins and broadly rounded ends, 15.0–40.0 µm long and 5.0–7.0 µm wide. These features, together with raphe structure and areolar shape are compared with several similar taxa currently ascribed to Sellaphora.


Phytotaxa ◽  
2021 ◽  
Vol 508 (2) ◽  
Author(s):  
DMITRY CHUDAEV ◽  
INGRID JÜTTNER ◽  
BART VAN DE VIJVER

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.


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