Fottea, 2012 (vol. 12), issue 2
Revision of type materials of antarctic diatom species (Bacillariophyta) described by West & West (1911), with the description of two new species.
Bart Van de Vijver, Ines Tavernier, Thomas B. Kellogg, John Gibson, Elie Verleyen, Wim Vyverman, Koen Sabbe
Fottea 12(2): 149-169, 2012 | 10.5507/fot.2012.012
In 1911, W. & G.S. West published a detailed account of freshwater algae collected by James Murray in the vicinity of Cape Royds on Ross Island (Antarctic Continent). Out of of 84 algal taxa reported, 30 were diatoms. Although the majority of the diatoms were considered (at that time) to be cosmopolitan, eight diatom species and two varieties were described as new. While most of these new taxa are still commonly reported from Antarctic and Subantarctic localities, the exact identity of some remains uncertain. Here we document the morphology of these species from the original type material using light and scanning electron microscopy; the taxonomic...
Ultrastructure of Aulacoseira brasiliensis sp. nov. (Coscinodiscophyceae) and comparison with related species.
Priscila Izabel Tremarin, Thelma Alvim Veiga Ludwig, Lezilda Carvalho Torgan
Fottea 12(2): 171-188, 2012 | 10.5507/fot.2012.013
This paper describes and illustrates Aulacoseira brasiliensis Tremarin, Torgan et T. Ludwig sp. nov. under light and electron microscopy and compares their ultrastructure with similar species obtained from Hustedt's collection samples. The new species is characterized by forming short chains linked by ovate-attenuate spines, rounded areolae occluded by vola, undeveloped ringleist and sessile rimoportulae arranged in two circumferential alternate rows. The spines shape, rimoportulae disposition, valve surface and mantle areolation pattern are very particular. The ultrastructural features of the frustules of A. brasiliensis are compared with those...
Achnanthidium delmontii sp. nov., a new species from French rivers.
Florence Pérès, A. Barthès, Etienne Ponton, Michel Coste, Loïc Ten-Hage, René Le-Cohu
Fottea 12(2): 189-198, 2012 | 10.5507/fot.2012.014
A new freshwater diatom species belonging to the genus Achnanthidium Kütz. has been found in several French rivers namely those of the Languedoc-Roussillon and Rhin-Meuse regions. Achnanthidium delmontii sp. nov. is described based on light and scanning electron microscopy observations. This species belongs to the group of Achnanthidium taxa with terminal raphe fissures curved to the same side of the valve and it is compared to the most related species: Achnanthidium pfisteri Lange-Bertalot, Achnanthidium pyrenaicum (Husdedt) Kobayasi, Achnanthidium temniskovae Ivanov et Ector and Achnanthidium zhakovschikovii...
New species in the marine diatom genus Olifantiella (Bacillariophyta, Biraphidineae) from Rodrigues Island (Western Indian Ocean).
Catherine Riaux-Gobin*, Adil Yousif Al-Handal
Fottea 12(2): 199-217, 2012 | 10.5507/fot.2012.015
Olifantiella Riaux-Gobin et Compère (Bacillariophyta, Biraphidineae), a monospecific diatom genus from coral reef environments in Réunion Island (Western Indian Ocean), was collected from Rodrigues Island (easterly island of the Mascarene archipelago) in 2007. Several taxa with the external characteristics of Olifantiella were observed in shallow lagoon sediments. The external opening connected to the internal process is easily identified in each taxon. The processes are on the same or opposite side of the frustule, depending on the taxon. Several taxa are present: 1) Olifantiella cf. mascarenica Riaux-Gobin et Compère,...
Sexual reproduction in the newly-described blue diatom, Haslea karadagensis.
Nickolai A. Davidovich, Romain Gastineau, Pierre Gaudin, Olga I. Davidovich
Fottea 12(2): 219-229, 2012 | 10.5507/fot.2012.016
For decades, the diatom genus Haslea has been known to comprise both "colorless" species and one species containing a blue pigment, the latter being known as H. ostrearia. Recently, a new blue diatom named H. karadagensis has been isolated from the Black Sea. The mating compatibility of the two species has been tested, and their reproductive isolation confirmed. We provide a detailed description of the heterothallic sexual reproduction process in this new species. Cells from clones which are sexually compatible arrange gametangial pairs. Each gametangium in the pair produces two gametes, which to a large extent are morphologically and...
Genotypic diversity of Dictyosphaerium-morphospecies (Chlorellaceae, Trebouxiophyceae) in African inland waters, including the description of four new genera.
Lothar Krienitz, Christina Bock, Kiplagat Kotut, Thomas Pröschold
Fottea 12(2): 231-253, 2012 | 10.5507/fot.2012.017
Trebouxiophytes of the Dictyosphaerium-morphotype from inland waters of Africa were studied using a polyphasic approach of SSU and ITS rDNA phylogeny, secondary structure of the ITS and observations made with a light microscope. Although the morphological criteria for differentiating species and genera are scarce, the genetic diversity of these algae was very high. Based on our genetic analysis findings, we described four new genera containing five new species: Compactochlorella dohrmannii, Compactochlorella kochii, Kalenjinia gelatinosa, Marasphaerium gattermannii and Masaia oloidia. Diversity and distribution...
Slow evolution of 1506 group I intron in Spirogyra Link 1820 (Zygnematophyceae, Streptophyta), a fast evolving lineage in the Zygnemataceae.
Charlotte Chen, Michael Schagerl
Fottea 12(2): 255-272, 2012 | 10.5507/fot.2012.018
Phylogenetic analyses of SSU rDNA sequences of 130 Spirogyra strains have revealed that these strains were subdivided into eight clades. Approximately 60% of the assessed strains (clades A-D) contain a 1506 group I intron, whereas strains without introns form individual clades (E-H). The Spirogyra intron shared the common insertion site of the Zygnematalean intron (position 1506 relative to the Escherichia coli small-subunit rRNA). Phylogenetic analyses of the Spirogyra group I intron showed the monophyletic origin within the Zygnematophyceae. Therefore, we assume the secondary loss of the intron in clades E-H is caused by the high evolutionary...
Ultrastructure of vegetative cells and autospores of an aerophytic strain of Vischeria stellata (Chodat ex Poulton) Pascher (Eustigmatophyceae) from Bulgaria.
Georg Gärtner, Maya P. Stoyneva, Blagoy A. Uzunov, Antonia D. Mancheva, Elisabeth Ingolić
Fottea 12(2): 273-280, 2012 | 10.5507/fot.2012.019
During investigation of the algal flora in the area of the Natural rock phenomenon and protected area Belogradchishki Skali (Bulgaria), an aerophytic strain of Vischeria stellata (Chodat ex Poulton) Pascher was taken in culture and analyzed by means of light (LM) and transmission electron microscopy (TEM). In the present paper some new data obtained on the architecture of vegetative cells and autospores (e.g. cell wall structure, pyrenoid development and organization) are provided as addition to the knowledge on the ultrastructure of this species.
Shape dynamics of silica scales (Chrysophyceae, Stramenopiles) associated with pH.
Yvonne Němcová, Martina Pichrtová
Fottea 12(2): 281-291, 2012 | 10.5507/fot.2012.020
We investigated the shape dynamics of silica scales in relation to environmental pH in two freshwater algal flagellates, Mallomonas striata and Synura echinulata, using landmark-based methods of geometric morphometrics. pH has been implicated as a primary factor controlling the occurrence and distribution of these protists. Moreover, scales are preserved in sediments and provide important proxy data of past and recent environmental changes. We concluded that the pH of the cultivation medium significantly affected scale biogenesis and influenced the final shape of produced silica scales. In addition, we asked how size of the scales was...
New and remarkable desmids (Zygnematophyceae, Streptophyta) from Europe: taxonomical notes based on LM and SEM observations.
Jan Šťastný, Frans A.C. Kouwets
Fottea 12(2): 293-313, 2012 | 10.5507/fot.2012.021
In the present paper, the morphology and taxonomy of seven desmid taxa collected in various European habitats is discussed, mainly on the basis of scanning electron microscopic observations of cell wall sculpturing. Four taxa (Actinotaenium riethii, Closterium pseudocostatum, Cosmarium discrepans and C. hostensiense) are newly described and the name of one taxon (Cosmarium lenzenwegeri) is recombined. In addition, the morphology of Cosmarium cataractarum and C. cinctutum is described in greater detail, confirming their status as independent species.
Identification and characterization of a new Halomicronema species (Cyanobacteria) isolated from the Mediterranean marine sponge Petrosia ficiformis (Porifera).
Carmela Caroppo, Patrizia Albertano, Laura Bruno, Mariarosa Montinari, Marco Rizzi, Giovanni Vigliotta, Patrizia Pagliara
Fottea 12(2): 315-326, 2012 | 10.5507/fot.2012.022
A filamentous cyanobacterium (strain ITAC101) isolated from a Mediterranean sponge (Petrosia ficiformis) was characterized by a combined phenotypic and genetic approach. Morphological and ultrastructural observations were performed along with growth measurements and pigment characterization. The molecular phylogenetic analyses were based on the sequencing of the 16S rRNA gene. In culture conditions, strain ITAC101 is moderately halophilic and grew in the range 0.3-7.6% (w/v) salinity with the optimum at 3.6%. Cell dimensions, thylakoid arrangement and pigment composition of this cyanobacterium fit the Halomicronema genus description,...
A new red colonial Pseudanabaena (Cyanoprokaryota, Oscillatoriales) from North American large lakes.
Hedy J. Kling, H. Dail Laughinghouse IV, Jan marda, Jiří Komárek, Judy Acreman, Karl Bruun, Sue B. Watson, Feng Chen
Fottea 12(2): 327-339, 2012 | 10.5507/fot.2012.023
A new morphotype of the genus Pseudanabaena (Cyanoprokaryota, Oscillatoriales) was identified from bloom samples of Aphanizomenon flos-aquae Ralfs ex Bornet et Flahault taken from large central North American water bodies, Lake Winnipeg (LWPG) and Lake of the Woods (LOW), which drains into Lake
Winnipeg (Fig. 1) and a strain of this morphotype was isolated from LOW in the fall of 2009. Here we describe the morphology and basic ecology, cytology and phylogenetic position of this new chromatic adaptive and colony forming planktonic species and propose a new species Pseudanabaena rutilus-viridis Kling et al. Preliminary research...
Morphological and molecular study of epipelic filamentous genera
Phormidium, Microcoleus and Geitlerinema (Oscillatoriales, Cyanophyta/Cyanobacteria).
Petr Hašler, Petr Dvořák, Jeffrey R. Johansen, Miloslav Kitner, Vladan Ondřej, Aloisie Poulíčková
Fottea 12(2): 341-356, 2012 | 10.5507/fot.2012.024
Filamentous epipelic cyanobacteria were isolated from ponds and lakes in the Czech Republic, Austria and Italy. Morphological and genetic variation of 20 isolated strains within the genera Geitlerinema, Microcoleus and Phormidium were studied. Partial sequences of the 16S rRNA gene were used for phylogenetic analyses, and secondary structure of the 16S-23S ITS region was used to additionally define clades. Morphological and molecular were congruent, and we were able to identify the majority of strains correctly to species on the basis of morphological features. Overall diversity and morphological/genetic variation of epipelic species...