Observations on new and rare species of freshwater diatoms from Cape Cod, Massachusetts, USA

2005 ◽  
Vol 83 (4) ◽  
pp. 362-378 ◽  
Author(s):  
Peter A Siver ◽  
Paul B Hamilton

The freshwater diatom flora of Cape Cod, Massachusetts, USA, was recently described using surface sediments from 56 largely glacial kettle lakes scattered over the narrow peninsula. During our examination we had the opportunity to study seven rare and interesting taxa with light (LM) and scanning electron microscopy (SEM). Two of these organisms, Neidium statuarium Hamilton & Siver sp.nov. and Stenopterobia pseudodelicatissima Siver & Hamilton sp.nov., are described as new species. Two new combinations, along with emended descriptions based on SEM, are provided for Nupela vitiosa (Schimanski) Siver & Hamilton comb.nov. and Tryblionella scalaris (Ehrenberg) Siver & Hamilton comb.nov. Morphological details of three additional and rare species, Neidium fasiatum Østrup, Neidium sp., and Tryblionella plana var. fennica (Hustedt) Simola are also provided. The relationships of each taxon to other similar species are discussed.Key words: Cape Cod, Neidium, new species, Nupela, Stenopterobia, Tryblionella.

Phytotaxa ◽  
2016 ◽  
Vol 272 (2) ◽  
pp. 134 ◽  
Author(s):  
WEI ZHANG ◽  
XIN QI ◽  
J. PATRICK KOCIOLEK ◽  
LI-QING WANG ◽  
RUI-LEI ZHANG

During a survey of freshwater diatoms from streams in the Xianju National Park, Zhejiang Province, China, a new cymbelloid species, Oricymba xianjuensis sp. nov. has been recorded. This species is assigned to the genus Oricymba by virtue of having a ridge separating the valve face and mantle, the presence of apical pore fields, and areolar openings with dentate occlusions. A detailed morphological description of the new species O. xianjuensis is presented, based on light and scanning electron microscopy. Oricymba xianjuensis sp. nov. is characterized by having a ridge along the valve face, as well as a linear-lanceolate outline with a moderately gibbous central portion gradually tapering towards the round, slightly protracted poles, a slightly lateral raphe with widened proximal endings and strongly deflected distal endings, and radiate striae. The taxon is morphologically compared with similar species of the genus Oricymba. The new species looks most similar to O. latirotundata, but is separated from this species by having more narrow, linear valves and a more tumid ventral margin. These findings add to our understanding the morphology and distribution of the genus Oricymba in China.


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 ◽  
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.


Phytotaxa ◽  
2014 ◽  
Vol 184 (4) ◽  
pp. 208 ◽  
Author(s):  
Priscila Izabel Tremarin ◽  
Thelma Ludwig ◽  
Lezilda Torgan

Examination of samples from different aquatic environments from Brazil revealed the presence of a new Aulacoseira species. Aulacoseira veraluciae Tremarin, Torgan & T. Ludwig is described and illustrated with light and scanning electron microscopy, and its morphology compared with that of similar species, such as A. muzzanensis (Meister) Krammer, A. granulata (Ehrenberg) Simonsen and A. agassizii (Ostenfeld) Simonsen. The new species is characterized mainly by the straight pervalvar rows of areolae, morphology of the linking spines, shape and position of the rimoportulae on the valve mantle, deepness and thickness of the ringleiste.


Phytotaxa ◽  
2016 ◽  
Vol 247 (1) ◽  
pp. 62 ◽  
Author(s):  
Gisele Carolina Marquardt ◽  
Angélica Cristina Righetii Da Rocha ◽  
Carlos Eduardo Wetzel ◽  
Luc Ector ◽  
Carlos Eduardo de Mattos Bicudo

Recent research of the plankton and the surface sediments from Ribeirão do Campo reservoir (São Paulo, southeast Brazil) led to identification of two new cymbelloid diatom species: Encyonema acquasedis sp. nov. and Kurtkrammeria salesopolensis sp. nov. Their morphology was studied under both light and scanning electron microscopes aiming at describing the two species in detail. The morphology of each species is compared and discussed with morphologically similar taxa. The new species are different from all others in the Cymbellales due to a combination of characteristics including valve outline, striae, areolae structure, and raphe system. Both species were collected from an oligotrophic environment with both low pH and conductivity.


Phytotaxa ◽  
2020 ◽  
Vol 439 (2) ◽  
pp. 150-158
Author(s):  
TING WANG ◽  
JIA-LIN WANG ◽  
QI-CHAO ZHOU ◽  
DMITRY A. CHUDAEV ◽  
J. P. KOCIOLEK ◽  
...  

In this study, we describe a new freshwater diatom, Navicula daochengensis sp. nov., which was found in a small mountain lake, Lake Congqiancuo, Haizishan Nature Reserve, Daocheng County, Sichuan Province, China. The detailed morphological description of the new species is provided from light and scanning electron micrographs. Navicula daochengensis has a narrowly lanceolate valve outline with broadly-rounded ends. The striate are radiate and convergent to the apices. This new species is compared with similar species, such as Navicula elongata, N. venerablis, N. moralesii and N. radiosa, which differ in size, valve shape, striae density and ultrastructure.


Phytotaxa ◽  
2020 ◽  
Vol 429 (1) ◽  
pp. 57-64
Author(s):  
BART VAN DE VIJVER ◽  
PETRA BALLINGS ◽  
CHARLOTTE GOEYERS

During a survey of the freshwater diatom flora of the sub-Antarctic Campbell Island, located in the southern Pacific Ocean, an unknown freshwater diatom was observed forming long colonies using linking spines. Detailed morphological analysis based on light and scanning electron microscopical observations and comparison with all known Frankophila taxa worldwide justified the description of this unknown taxon as a new species within the genus Frankophila: Frankophila dalevittii Van de Vijver & Goeyers sp. nov. The new taxon is characterized by the presence of well-developed linking spines, the absence of external raphe slits and the presence of internal raphe slits, biseriate striae composed of relatively large areolae and a large axial area. Despite the absence of the external raphe slits, the species is best placed within the genus Frankophila. The new species is described and illustrated and compared with all other Frankophila taxa.


Phytotaxa ◽  
2019 ◽  
Vol 404 (1) ◽  
pp. 12 ◽  
Author(s):  
WEI ZHANG ◽  
TING WANG ◽  
ZLATKO LEVKOV ◽  
INGRID JÜTTNER ◽  
LUC ECTOR ◽  
...  

During a survey of freshwater diatoms from a mountain lake, Lake Congqiancuo, Haizishan Nature Reserve, Yading, Daocheng County, Sichuan Province, China, a new Halamphora species, Halamphora daochengensis sp. nov. was found. A detailed morphological description of the new species is presented, based on light and scanning electron microscopy. The main features of H. daochengensis are dorsiventral, semi-lanceolate valves with a strongly triundulate dorsal margin and valve ends distinctly protracted and capitate. The new species is compared with other similar species including Halamphora dusenii and H. normanii var. undulata which differ in size, valve shape, stria density and ultrastructure.


Phytotaxa ◽  
2018 ◽  
Vol 373 (3) ◽  
pp. 231 ◽  
Author(s):  
QI LIU ◽  
LIN YANG ◽  
FANGRU NAN ◽  
JIA FENG ◽  
JUNPING LV ◽  
...  

A new species, Aneumastus yamdrokensis Liu & Xie, is described from Yamdrok Lake, collected during a survey of the freshwater diatom flora of Tibet, China. The valves of this new species are elliptical-lanceolate with rounded apices and have the features typical of the genus, including complex areolae. The morphology of A. yamdrokensis is documented with light and scanning electron microscopy, described in detail, and compared with the most similar taxa, including A. minor Lange-Bertalot and A. densistriatus.


Phytotaxa ◽  
2014 ◽  
Vol 161 (2) ◽  
pp. 139 ◽  
Author(s):  
Cheikh Abdoul Kader Fofana ◽  
El Hadji Sow ◽  
Jonathan Taylor ◽  
Luc Ector ◽  
Bart Van De Vijver

During a survey of the freshwater diatom flora of the Senegal River, an unknown Placoneis species was observed that was initially identified as Placoneis gastrum. Detailed morphological analysis using both light and scanning electron microscopy observations revealed sufficient morphological differences to separate this species as Placoneis cocquytiae sp. nov. The new species is characterized by a rather broadly lanceolate to elliptic-lanceolate valve outline with rostrate, protracted, broadly rounded apices. The central area has an irregular shape due to the shortening of several striae. An isolated pore is lacking. The new species is compared with similar Placoneis and Navicula s.l. taxa and a short biogeographical analysis based on confirmed African records is presented. So far, P. cocquytiae is also present in Zambia and Lake Tanganyika. 


Sign in / Sign up

Export Citation Format

Share Document