Species Of Nitella Research Articles

Tolypella mongolica (Charophyceae, Characeae): A new dioecious charophyte species from the center of Eurasia and implications for charophyte taxonomy, including the validation of T. porteri and the new combination for T. jwalae

A new dioecious species of Tolypella, T. mongolica sp. nov. from the section Tolypella, was described using an integrative taxonomy. It was found in three distant localities – shallows of a brackish small lake and a channel in the midland steppe in Mongolia and the Altai Mountains, and a small brackish water body in the dry steppe in Southeast Europe. It differs from other species in rbcL and ITS sequences and in distinct complex ornamentation of the oospore surface, varying from sparsely coarsely tuberculate to having the appearance of an aerial view of mountain landscape with acute to mostly sharp edges of elements at probably the ripest stage. Wide intrapopulation variability of expression of this trait, only partly explainable by oospore ripening stage, was found and illustrated for two populations, indicating previous underestimation of this phenomenon in taxonomic research. T. mongolica is richly fertile and appears to be ephemeral as most species of this genus. Only female plants were found in all localities. The absence of male plants could be referred to either their earlier development during the growing season or, less likely, parthenogenesis in this species. The description of the new species suggests taxonomic changes for two dioecious species of charophytes. Tolypella porteri stat. et comb. nov. was validated here. T. jwalae was recognized as a species of Nitella, N. jwalae comb. nov.

Actual diversity and distribution of charal algae of the genus <i>Nitella</i> C.Agardh (Charophyta) in Ukraine)

The results of the analysis of literature and original data on the species diversity and distribution patterns of algae of the genus Nitella C.Agardh (Charophyta, Charales) in Ukraine are presented. Now, the diversity of the genus Nitella in Ukraine is represented by 9 species out of 13, known in the Europe flora of Charales, namely: Nitella capillaris (Krock.) J.Groves et Bull.-Webst., N. confervacea (Bréb.) A.Braun ex Leonh., N. gracilis (Sm.) C.Agardh, N. flexilis (L.) C.Agardh, N. mucronata (A.Braun) Miq., N. opaca (C.Agardh ex Bruz.) C.Agardh, N. syncarpa (Thuill.) Chev., N. tenuissima (Desv.) Kütz. and N. translucens (Persoon) C.Agardh. An annotated list of Ukrainian species in Ukraine. A total of 78 locations have been registered, including historical, lost, and modern ones. Most of them were found within the Pripyat-Desnianska (PpDSAP) (50) and Serednyodniprovska (SDpAP) (21), much less  within the Dnieper-Black Sea (DpAp) (3) and Carpathian-Danube (CpDnAP) (4) algofloristic subprovinces. It is suggested that main limiting factors influencing on diversity and distribution patterns of the Nitella species in Ukraine are the type of waterbodies, temperature, a degree of minimalization as well as chemical main ionic composition of water and active reaction (pH) of water.

Charophytes of Australia’s Northern Territory – II. Tribe Nitelleae

This study of Northern Territory charophytes deals with the tribe Nitelleae in family Characeae. We recognise 16 species of Nitella for the Territory. The list includes seven previously described species (Nitella belangeri, N. biformis, N. congesta, N. heterophylla, N. micklei, N. myriotricha and N. tumulosa, of which N. belangeri and N. tumulosa are newly recorded for the Australian flora), and nine newly described species (N. acanthospora, N. boreali-australis, N. crocodylus, N. limosa, N. martinii, N. nitida, N. oollooensis, N. silicea and N. townsendii). Of the five previously reported Nitella species in the Northern Territory (N. hyalina, N. myriotricha, N. penicillata, N. pseudoflabellata and N. subtilissima), only N. myriotricha is recorded in this study, because the other records were based on erroneous identifications or localities. All Nitella species described here can be distinguished on the basis of their morphology and reproductive arrangement. Keys, illustrations and descriptions of all the species are provided.

<p><strong>Molecular taxonomic report of <em>Nitella megacephala sp. nov.</em> (Characeae, Charophyceae) from Korea</strong></p>

We report a new taxonomic entity of Nitella megacephala sp. nov. (Charales, Charophyceae) from Korea. The characean algae collected from two sites (Haenam-gun and Kangjin-gun) had distinctive morphological characteristics representing a new Nitella species. Those samples showed a light-green color in gross morphology and a plant body length up to 13 cm. Moreover, the two-celled dactyls and head formation differed clearly from closely related Nitella species (N. moriokae, N. spiciformis, and N. translucens). From a molecular phylogenetic analysis of rbcL DNA sequences, Nitella megacephala sp. nov formed a single clade with N. translucens, N. moriokae and N. spiciformis, and was distantly related to those three species as a sister taxon. In the terms of interspecific sequence variation, Nitella megacephala showed 3.2–5.5% pairwise distance values with sister groups in phylogenetic tree (N. translucens, N. moriokae and N. spiciformis) and 3.2–9.1% with other of Nitella species. In contrast, its sister group species differed 0.3–1.7% at the interspecific level. These unique morphological and molecular taxonomic characteristics clearly support the establishment of this taxonomic entity as a new species in the genus Nitella (Nitella megacephala sp. nov.)

Taxonomy and phylogeny of Nitella (Charophyceae, Characeae) from Brazil with emphasis on the midwest and southeast regions

The genus Nitella is the most species-rich within the Charales. Brazilian studies on the genus are relatively scarce and consist of floristic surveys, lacking modern and more precise information. This investigation applied scanning electron microscopy to analyze the oospore wall and molecular data associated with traditional morphological characters to analyze forty-two populations of Nitella from the midwest and southeast regions of Brazil. Forty-two new sequences of rbcL, twelve of ITS1 and twenty-three of ITS2 were generated for the five species recognized in this study: Nitella acuminata A. Braun ex Wallman, Nitella axillaris A. Braun, Nitella elegans B. P. Pal, Nitella flagellifera J. Groves & G. O. Allen and Nitella microcarpa A. Braun.. Phylogenetic analyses of sequences of these three markers were congruent in that they grouped our species with others from different countries to form five clades. Our results on ultrastrucure of the oospore wall were consistent with previous studies for the same species from other regions of the world. The data reinforced the conclusion that the use of ornamentation of oospore wall may be extremely useful for the construction of a natural system for Characeae at section level. Molecular evidence, reinforced by morphological data, for the Brazilian material analyzed suggests that Nitella subglomerata A. Braun and Nitella gollmeriana A. Braun could be synonymys of Nitella acuminata; and Nitella axilliformis K. Imahori appears to be the same as Nitella axillaris. However, no formal proposition was made considering that type specimens were not analyzed and these observations were based on a relatively small number of samples strictly from Brazil. We showed that even among geographically distant populations, such as from other continents, of some Nitella species, the degree of identity among DNA sequences was high.

Identification of a new characteristic species of Nitella (Charophyceae) from southwestern China based on morphology and molecular phylogeny

Nitella fuiana Lan & Qing sp. nov., a special kind of charophyte from Mingshan, Sichuan, China, was described in this study. The systematic position of the new species was assessed based on morphological and molecular analysis. The results of morphology comparison showed that the charophyte possessed stipulodes and 10-cell coronula. Nuclear 18S rDNA and plastid rbcL sequences analysis revealed that N. fuiana was a single clade as clustered with other species of Nitella. Combined with the morphological and molecular analysis data, our study strongly supported that N. fuiana was a new species of Nitella. This is the first report of Nitelleae species with stipulodes, which increased the morphological diversity of charophytes. This study also reminds us to pay close attention to the characteristics of stipulodes for further research on charophytes.

Species of Nitella (Charophyceae, Charales) from Israel: low species richness and rare occurrence

Species of Nitella (Charophyceae, Charales) from Israel: low species richness and rare occurrence

Виды рода Nitella (Streptophyta: Charales) в Мурманской области

Seven new records of Nitella are published from Murmansk Oblast (Russia) following recent revision of specimens deposited in KPABG and IBIW. The new records relate to N. flexilis (L.) C. Agardh, N. opaca (Bruz.) C. Agardh, or Nitella sp. ster. (flexilis vel opaca), and they are the first records for the south and south-east part of the region. A list of all records of Nitella species has been compiled together with a map. These species of Nitella do not seem to be rare in Murmansk Region, and the sparsity of their recorded distribution probably reflects insufficient local study of this group. New records of Nitella and other Charales are expected in the future, and these may provide significant insights into the ecology of charophytes in higher latitudes.

New Record of Chara Hispida (L.) Hartm. (Streptophyta: Charophyceae, Charales) from the Işıklı Lake (Turkey) and Critical Checklist of Turkish Charophytes

Chara hispida (L.) Hartm. has been found in the Isikli Lake (Western Anatolia). The specimens are described; distribution and ecology of C. hispida are discussed. The bio-indication shows that the Isikli Lake is mainly an oligotrophic state with a trend to a mesotrophic state, and fresh low-alkaline water with low to middle organic pollution. A check-list of charophytes was compiled. There are sixteen species of charophytes known from Turkey, including 13 species of Chara and 3 species of Nitella.

The charophytes (Charales, Charophyceae) of Mongolia: a checklist and synopsis of localities, including new records

A species list of charophytes is compiled for Mongolia (Outer Mongolia) based on previously reported and original data. To date, 16 species of charophytes are known from the territory, including 2 species of Nitella and 14 species of Chara. One of the latter, Chara virgata Kutz., is found in Mongolia for the first time. A specimen description is provided and the locality environment described. The known charophyte flora of Mongolia consists mainly of cosmopolitan and widespread species. A newly compiled synopsis of charophyte localities contains 38 water bodies including 25 from which species names are known. A map of previously reported and 9 new localities is given. The localities of 19th century collections are clarified; almost all fall outside recent Mongolian territory. The species found most frequently are Chara tomentosa, C. altaica, C. aspera and C. contraria. Probable regional hotspots for charophyte finds are revealed. These are important for charophyte conservation in Mongolia.

Two new species of Nitella (Characeae, Charophyceae) from arid-zone claypan wetlands in Australia

Two new species of Nitella Ag. are described. The species are dioecioud and grow in temporary arid-zone wetlands called claypans. Both have somewhat inflated, bicelluate fertile dactyls and neither sp

Strigolactones affect development in primitive plants. The missing link between plants and arbuscular mycorrhizal fungi?

Strigolactones affect development in primitive plants. The missing link between plants and arbuscular mycorrhizal fungi?

The impact of phosphorus enrichment on a Nitella sp. from sand-mine void wetlands, Capel, Western Australia

The disappearance of submerged macrophytes in shallow lakes is one of the most critical problems caused by eutrophication. The impact of increased phosphorus concentration on the establishment of a Nitella species as a suitable macrophyte for the rehabilitation of sandmine void wetlands at Capel in Western Australia, in the context of an imminent proposal to discharge effluent water from a waste processing plant into the wetlands was studied in the laboratory. The Nitella species was cultured in aquarium tanks in eutrophic and mesotrophic concentrations of phosphorus with a control (oligotrophic) treatment and its growth and lifecycle were monitored. It was observed that eutrophication had a significant impact on growth, morphology and lifecycle of Nitella. In addition to showing profuse vegetative growth, Nitella species produced no reproductive organs in the eutrophic medium. An approximate ratio of 1:1 male to female reproductive organs was recorded in the mesotrophic and control treatments but with reduced vegetative growth. Higher biomass of Nitella and filamentous algae including blue green algae was also recorded in the eutrophic treatment. In the eutrophic medium, the height, number of nodes, internode distance and the biomass were also found to be significantly higher than those in the other treatments. It was concluded that with the projected discharge of waste water into the Capel Wetlands, the Nitella meadows would display an initial accelerated growth followed by excessive growth of filamentous algae including cyanobacteria leading to increase in turbidity and eventual disappearance of Nitella species.

Self-organizing maps of Kohonen as means of Chara and Nitella species distribution diagnostic

Boszke P. and Astel A.M. 2010. Self-organizing maps of Kohonen as means of Chara and Nitella species distribution diagnostic. Phycologia 49: 592–603. DOI: 10.2216/09-72.1This study deals with the exploration of oospores morphometric variability according to various types of water reservoirs of Poland by the self-organizing maps (SOM). The SOM integrates morphometrical features in order to distinguish genera and species and to explore their natural environmental habitats. The data set covered 575 oospores collected in Poland and contained measurements of largest polar axis (LPA), largest equatorial diameter (LED), isopolarity index, number of ridges and width of fossa (WF) of 15 Chara and Nitella species. Biometric analysis of oospores revealed that Chara and Nitella genera could be easily distinguished by the SOM. LPA and LED of C. contraria oospores collected from lakes were higher than in case of those found in peat bogs. LPA, LED and WF of C. globularis that were found in lakes were higher than the ones of charophytes from ponds and ditches. The most taxonomically useful morphometrical features for oospores identification are LPA, LED and WF. The advantages of SOM algorithm in the form of exceptional visualization, dimension reduction and exploration abilities are stressed.

Ultrastructure of mature male gametes of Nitella hyalina (Charales, Charophyta)

Vouilloud A.A., Cáceres E.J. and Leonardi P.I. 2010. Ultrastructure of mature male gametes of Nitella hyalina (Charales, Charophyta). Phycologia 49: 508–511. DOI: 10.2216/09-111.1This article describes the ultrastructure of male gametes of Nitella hyalina. Microtubular roots did not surround mitochondria completely. The number of microtubules varied from 12 to19 at the level of mitochondria, from 24 to 31 at the level of the nucleus and from 10 to 21 at different levels of the plastids. The three-membered root is clearly discernible only up to the level of mitochondria. At the rearmost level of the gamete, microtubules were separated in bunches of two to six microtubules each. Mature gametes of N. hyalina were compared with those of other species of Chara and Nitella. This comparative analysis suggests that certain male gamete ultrastructure traits are regularly dissimilar at genus level.

Aproximación a las comunidades de carófitos que existieron en la Albufera de Valencia a partir del estudio de las oósporas del sedimento

Charophyte oospores and their features (size, shape, colour, outer wall ornamentation, etc.) are able to persist in seed banks of aquatic ecosystems. Thus, these characteristics can be used for taxonomic species identification, thereby providing knowledge about the specific composition of the charophyte community in a habitat that currently lacks, or has greatly altered, submerged vegetation. Several years ago, l’Albufera de Valencia lost the charophyte meadows that covered the lake bottom in the past, which had never been studied in detail. Several sediment cores were extracted from the lagoon at three sites and the oospores and gyrogonites were isolated and characterized. The oospore/gyrogonite densities in the sediment layers were estimated. Ten different taxa have been identified: six belonging to genus Chara [Ch. vulgaris, Ch. Hispida var. major , Ch. fragilis (Ch. globularis), Ch. Hispida var. baltica, Ch. aspera, Ch. tomentosa]; one Nitella species (N. hyalina), two Tolypella species ( T. glomerata and T. hispanica ) and one Lamprothamnium species ( L. papulosum ). The latter, which indicates the period when water salinity was high in the lagoon, was found in the deepest sediment layers. An increase in the oospore abundance and diversity was observed in line with sediment depth. This indicates, on the one hand, that the lagoon went through different ecological stages (with important changes in salinity, mainly) and, on the other hand, the eutrophication process that the lagoon has been undergoing for at least the last 45 years, has progressively affected the abundance and diversity of the charophyte community.

Oospore variation in Nitella gracilis and Nitella mucronata (Charales, Charophyceae) from Poland

The determination of the members of Charales (Charophyceae) is not easy. The main reason of this is a wide range of variation in vegetative characters within most of the species. Many features such as the extent of branchlet cortication, the degree of incrustation, length and number of bract cells, spine cells, stipulodes, diameter of the main axis and oospore size and color do not have universal taxonomic significance. In similar, many Nitella species characters such as: general habitus, branchlets and presence of the top segment (mucro), are helpful in determination, however they are often not developed. In this case, the features of oospore wall ornamentation revealed by light and scanning microscopy can be important taxonomic characters of the Charales. The present study shows interspecific variations of the oospore in two Nitella species from Poland which can be helpful in correct determination of both species. Some of the oospore features like number of striae and fossa width can not be used, as they appeared statistically unimportant, and cannot be used in distinguishing between both species. The presented results are the first detailed report of oospore wall ornamentation pattern from Poland for the species studied. Oospore features are presented in detail on the background of some additional tips and among them particularly: length and width of the oospore, ISI idex, width of fossa, width of striae and number of striae.

An overview of Nitella (Characeae, Charophyceae) in Australia

The genus Nitella Ag. in algal family Characeae is characterised by furcate (forked) branchlets, compressed oospores (i.e. oval in cross-section), terminal antheridia and a 10-celled coronula on the oogonium. Species of Nitella are submerged plants that grow in a variety of wetland and riverine habitats. Approximately 89 taxa of Nitella (species, subspecies, varieties and forms) have been described on the basis of Australian collections, and published estimates of the number of species range from 18 to >35. The lower value is based on the assumption that infra-specific variation is great, species have a wide distribution, monoecy and dioecy are not indicative of speciation and the number of furcations and the ratio of branchlet segment lengths vary for a species owing to the environment in which they grow. The higher value is based on evidence that morphological characters are relatively constant for a species, that oospore variation is a good indication of speciation and that monoecious and dioecious entities are not inter-fertile. An overview of Australian members of the genus is presented here as a framework for further taxonomic work. Representatives of all three subgenera of Nitella occur in Australia, with subgenus Nitella poorly represented, and subgenera Tieffallenia and Hyella equally speciose. The subgenera are defined here in relation to the Australian taxa they contain. In the present treatment, section Migularia is transferred from subgenus Tieffallenia to subgenus Hyella, and several species are transferred to subgenus Tieffallenia. Within subgenus Tieffallenia, variation in vegetative and oospore morphology is useful for distinguishing among sections and species. However, although members of subgenus Hyella display a similar range of variation in vegetative morphology, most of the species have similar, reticulate, oospore ornamentation. Australia is home to a large number of endemic species of Nitella, many of which are dioecious. The total number of species and the degree of endemism have been underestimated in earlier studies, and it is likely that more than 50 species of Nitella will be recognised on the basis of Australian specimens. A key to the subgenera, and keys to sections in the subgenera are provided.

Review: Taxonomy of Nitella (Charales, Charophyceae) based on comparative morphology of oospores and multiple DNA marker phylogeny using cultured material

SUMMARYThe genus Nitella is the largest group in the Charales and has the highest diversity of vegetative and oospore morphologies. In his worldwide monograph on the Charales, R. D. Wood characterized the sections and species of Nitella mainly on the basis of vegetative morphology and treated oospore wall morphology as diagnostic at the infraspecific level. Therefore, many species of Nitella exhibiting distinct external morphology of the oospore wall (EMOW) were reduced to infraspecific rank and only 53 of 204 species previously described were recognized within Nitella. However, recent morphological and molecular phylogenetic studies have demonstrated the phylogenetic validity of using EMOW for diagnosing some species of Nitella. More recently, a scanning electron microscopy (SEM) study of internal morphology of the oospore wall (IMOW) and multiple DNA marker analyses using both nuclear and chloroplast gene sequences were conducted to improve our understanding of the taxonomy of Nitella at the species level, on the basis of cultured material of a large number of species. Multiple DNA marker analyses resolved detailed and robust phylogenetic relationships within the genus and demonstrated the taxonomic and phylogenetic significance of IMOW. In addition, they supported the taxonomic decisions based on differences in oospore morphology, suggesting that an integrated approach, involving both SEM studies of the EMOW and IMOW and multiple DNA marker analyses, is appropriate to address problems at lower taxonomic levels within the genus, as well as to construct a natural taxonomic system for the genus. In this paper, recent morphological and molecular phylogenetic studies are reviewed and recent improvements in taxonomy of Nitella are summarized. Moreover, the evolution of morphological features and phylogenetic relationships within Nitella are discussed, focusing especially on oospore morphology.

Monoecious Nitella species (Characeae, Charophyta) from south-eastern mainland Australia, including Nitella paludigena sp. nov.

Identification of Australian species of Nitella is problematic. Several species of monoecious Nitella have been described from south-eastern mainland Australia, but identification of these based on current treatments has been difficult. In response to the discovery of a new monoecious Nitella from the swamps of the Fleurieu Peninsula in South Australia, the monoecious species of Nitella from south-eastern mainland Australia were examined and compared. N. paludigena M.T.Casanova & K.G.Karol is distinguished from other monoecious species on the basis of its overall vegetative morphology and oospore morphology. N. paludigena is found in peaty tea-tree (Leptospermum sp) swamps on the Fleurieu Peninsula in South Australia, and in the south-west of Victoria. A description of the morphology and ecology of the five monoecious Nitella species from south-eastern mainland Australia is given, along with a key.