Diversity Of Desmids Research Articles

Freshwater desmid diversity along Naga thrust: A hydrocarbon province of South-East Asia

Explorations were made to enumerate and document desmid diversity of the Naga thrust abounding crude oil contaminated waterbodies of Southeast Asia. A total of 111 desmid species were recorded belonging to 11 genera under 2 families. Among these, 25 desmid taxa were reported new to Indian flora whose detailed taxonomic account was given. Also, 69 desmid taxa were reported for the first time from the Naga thrust province. Cosmarium was the dominant genus amongst them with 32 species whereas Micrasterias (2 species) and Hyalotheca (2 species) showed least number of species representation.

The Spatio-temporal Variations of Phytoplankton Diversity of a Subtropical Sacred Lake of Meghalaya State, Northeast India

The spatio-temporal variations of phytoplankton diversity of the ‘de-mineralized’ sacred Thadlaskein Lake of Meghalaya state of northeast India are monitored based on analyses of the littoral and limnetic assemblages. Our study reveals a total of 51 species, depicts notable desmid diversity, and records the speciose constellation of 49 species per sample. Phytoplankton indicates importance vis-a-vis net plankton abundance and exhibits quantitative dominance of Charophyta; Chlorophyta > Bacillariophyta > Dinozoa > Chrysophyta are sub-dominant groups, and Cyanobacteria and Euglenozoa record poor densities. Closterium spp., Cosmarium spp., Scenedesmus spp. and Staurastrum spp. are noteworthy taxa, and eleven species contribute notably to phytoplankton abundance. Our results depict high species diversity, lower dominance and high evenness. Individual abiotic factors exert the differential spatial influence on phytoplankton, and register the relative importance of the rainfall, transparency and total hardness, while the CCA registers the moderate cumulative influence of 10 abiotic factors on the littoral and limnetic assemblages. The spatial variations of various aspects of phytoplankton diversity and the influence of abiotic factors are hypothesized to the habitat heterogeneity amongst the two regions. The present study is a useful contribution to the phytoplankton diversity of India and that of the subtropical lacustrine environs of the country.

Taxonomy and distribution of desmids in Karapuzha Dam, Western Ghats, Kerala

AbstractDuring the studies of algae in the Wayanad district, a notable diversity of desmids observed in the Karapuzha dam, Kerala, India. Karapuzha Dam is 700 to 2061 metres above sea level and is a part of Western Ghats. Thirty‐nine taxa of desmids were identified from Karapuzha Dam of Wayanad district from June 2019 to May 2020. The collection comprises ten genera of 39 desmids, including 24 species of Cosmarium, 5 Staurastrum, 2 Closterium, 2 Euastrum, 1 Gonatozygon, 1 Triplastrum, 1 Penium, 1 Spondylosium, 1 Micrasterias and 1 Arthrodesmus. Among these, Cosmarium regnesi var. montanum is new to India, 8 taxa are new to Kerala and 2 taxa are new to South India. Some rare and high altitude distributed species are found in the study. This desmid diversity relates to the oligotrophic nature of the dam. This paper is a pioneer attempt to document the desmid flora of Karapuzha Dam, Kerala.

How hidden is the diversity of the genus Cosmarium (Desmidiaceae) in the Brazilian Caatinga?

The Caatinga domain is the largest and most diverse tropical semiarid ecoregion of South America; however, little is known about the diversity of desmids it harbors, especially the genus Cosmarium (Desmidiaceae, Zygnematophyceae). Our study contributes to the knowledge of Cosmarium in the Caatinga through the report of 42 interesting taxa, including a new species (Cosmarium imperiale), 22 new records for South America, and 19 additions to the desmid flora from Brazil. The samples were gathered from periphytic material from the “Pantanal dos Marimbus” in the Chapada Diamantina region of Northeast Brazil. We provide taxonomic notes, ecological information, including habitat conditions with limnological data, and updated global distributions for all taxa of Cosmarium. A complementary quantitative study was performed during the last year of sampling (2018), which revealed that most taxa have their highest densities in the months with low precipitation and when the water's conductivity and transparency are greater. Our results also have implications for the conservation of the biota from Marimbus do Baiano and understand South America's desmids' biogeography since some rare taxa identified here were previously only known from other continents such as Europe and Africa.

Conjugates (Charophyta, Conjugatophyceae) of the Kader bog (Leningrad region, Kurgalsky reserve)

The Kurgalsky Nature Complex Reserve is located in the Kingisepp District of the Leningrad Region, 45 km northwest of Kingisepp. The territory of the reserve includes the Kurgalsky peninsula, as well as the adjacent waters of the Gulf of Finland. The Kader swamp massif is located in the south of the Kurgalsky Peninsula. The state of the autochthonous vegetation cover of the Kader swamp was considered in connection with the laying of the main gas pipeline under «the Nord Stream–2» project. The revealed high diversity of desmids (48 species), as well as their abundance, the frequency of occurrence and the presence of species rare in other habitats of the Leningrad region, indicates the inviolability of the freshwater algae flora, favorable environmental conditions in water bodies and the absence of anthropogenic transformation of the studied territory.

Algal Diversity of Ansupa Lake, Odisha, India

In the present investigation, algal samples were collected from six selected sites of Ansupa lake and altogether 72 algal species belonging to Cyanobacteria (11 species), Euglenophyceae (4 species), Bacillariophyceae (07 species), Chlorophyceae (17 species), Ulvophyceae (1 Species), Trebouxiophyceae (2 species), Zygnematophyceae (29 species) and Charophyceae (1 species) were recorded. Furthermore, our study was revealed that desmid diversity was dominant followed by green algae in the lake, which was indicating the oligotrophic condition of water in the lake.

MONITORING OF DRINKING WATER RESERVOIRS OF KOPARGAON CITY WITH SPECIAL REFERENCE TO ALGAL FLORA AT YESGAON, DIST. AHMEDHNAGAR MAHARASHTRA (M.S.), INDIA

Algal collection from 5 drinking water storage reservoirs of Kopargaon city was carried out for one year. A total 39 genera and 62 species belonging to four classes were encountered during investigation period. Present studies revealed that, algal population was not found homogenous throughout the year, but it showed seasonal variation. During monsoon the algal population recorded was less, which increases in winter and found more in summer season. Chlorophyceae was found to be the dominant group throughout the investigation period in all storage tanks consisting of large number of genera and species. Many planktonic, some benthic and epiphytic algae were encountered during investigation period at all five water storage reservoirs. The commonly occurred genera were Ankistrodesmus, Closterium, Cosmarium, Spirogyra, Ulothrix from class Chlorophyceae, while from Cyanophyceae, Merismopedia, Microcystis, Oscillatoria, and Lyngbya are dominating forms. Desmids wear found in dominant condition in all storage tanks indicating unpolluted condition of water. Maximum population of Cosmarium was recorded during summer season, while Closterium species were recorded throughout the year. Other genera recorded were Staurastrum, Xanthidium, Euastrum, Micrasterias, Arthrodesmus, Desmidium, etc. Diatoms were recorded more in number during winter, while Euglenophycean members were sparsely reported only in summer. During present studies tremendous variations in Desmid diversity was noticed during summer and winter as compared to monsoon season.

Diversity of desmids from freshwater bodies of Kohima district, Nagaland, India

Diversity of desmids from freshwater bodies of Kohima district, Nagaland, India

Taxonomic notes on the species of the genus Micrasterias (Desmidiaceae, Conjugatophyceae) from the Metropolitan Region of Salvador, Bahia, Brazil

We present the results of a taxonomic survey of the genus Micrasterias in the Metropolitan Region of Salvador (MRS), Bahia, northeastern Brazil during 2007–2010 and 2014–2015. A total of 275 phytoplanktonic and periphytic samples from 11 municipalities were analyzed. The samples were collected using a plankton net with 20 µm mesh or squeezed from macrophytes. Twenty-nine taxa were identified, which 20 have their geographic distributions expanded. Only M. pinnatifida was considered frequent, occurring in 9 municipalities, while we classified 21 species as rare in the study area. Our results emphasize the importance of the conservation of aquatic bodies in the MRS for the maintenance of biological diversity of desmids and other aquatic organisms.

Diversity and conservation of desmids in Bornholm, Denmark – revisiting after 130 years

Desmids are unicellular green algae dominating habitats that are vulnerable and highly threatened, like raised bogs, mires and fens. Here, we studied the desmid diversity in four different localities on the Danish island Bornholm. A total of 186 species, 58 of which not previously recorded from Denmark, were observed. The species composition of the locality ‘Kohullet’ was compared to more than 130 year‐old records. In the 1880s this locality contained 65 species vs 70 in in the present study. The species composition has changed towards more oligo‐mesotrophic and more acidophilic species. The reasons for these changes may be the 1960‒1970s’ increase in atmospheric deposition of nitrous‐ and sulphurous oxides leading to a pH‐decrease, and the possible use of Kohullet in the 1880s for cattle drinking leading to more mesotrophic conditions than present days conditions. We used an empirical system developed by Coesel for classifying the trophic state or ‘conservation value’ of freshwater habitats using desmids as indicator organisms. All localities studied had maximum scores, i.e. represented highly structured and well‐balanced ecosystems. Thirty of the recorded species were potential Red List species, using the Dutch Red List criteria for desmids. We suggest that Kohullet should be considered an Important Plant Area (IPA), as it has a high diversity of desmids, a long history of algal records including desmids and may be considered a threatened habitat of major significance to desmids. Furthermore, it is suggested that several desmids are considered Red List species.

Diversity of green algae in Kamanos raised bog (NW Lithuania) with the aspect of long-term changes in desmids

AbstractIn Kamanos raised bog, the green algae community was represented by 160 taxa distributed into eight Chlorophyceae orders. The diversity of desmids (93 taxa) that are an essential algal component of raised bogs was most relevant. Chlorococcales comprised 30 taxa and Ulotrichales – 15 taxa. Representatives from the rest green algae groups were scarce. Higher variety of habitats in Lake Kamanos and the pools supported more diverse flora of green algae (151 taxa) compared to black hollows (61 taxa). Actinotaenium cucurbita was the single species found in all studied water bodies of Kamanos raised bog. Characium ornitocephalum, Asterococcus superbus, Cosmarium amoenum, Micrasterias truncata, Spondylosium pulchellum, Netrium digitus were found in the lake and all pools, whereas Cosmoastrum scabrum, Tetmemorus laevis – in all hollows. In the current study, the composition of desmid taxa recorded in Kamanos raised bog in two research periods was compared. The first reports on desmids were published by Vilkaitis (1937, 1940). He found 129 Desmidiales (18 genera) and 10 Zygnematales species (4 genera). Fifty five species identified by V. Vilkaitis were found repeatedly during the current investigation. In 2005, 42 species were newly recoded in Kamanos raised bog, and of these, 17 taxa were new to desmid flora of Lithuania. A numerous rare species recorded by Vilkaitis (1937) were not observed repeatedly probably due to long-term changes that had occurred in the peat bog and not enough comprehensive study that represented only part of Kamanos wetland. Some new rare desmid species (e.g. Micrasterias jenneri, Cosmarium cymatonotophorum, Desmidium cylindricum, Actinotaenium cucurbitinum, Xanthidium bifidum) have recently been found at Kamanos sites.

Seasonal variations of physico-chemical factors and diversity of desmids (Algae) in Shahpura lake of Bhopal, India

The study aimed at determining the seasonal variations of physico-chemical aspects and their effects on diversity of desmids in Shahpura Lake of Bhopal, India. The physico-chemical parameters of the Lake, like, water temperature, transparency, pH, DO, total hardness, calcium hardness, chloride, phosphate, and nitrate were studied and data analyzed. The Desmidaceae taxa of winter, summer, monsoon and post monsoon seasons from December 2006 to November 2007 have been identified, resulting 36 species in 5 genera, and their monthly variations are presented.

A contribution to the desmid flora of Southeastern Maine1

Abstract Eight peat bogs and wetlands near Steuben, ME were sampled in July 2005 to assess local diversity of freshwater algae. A surprising number of conjugating green algae, especially from the order Desmidiales, was seen even in this small local sample, summing up to 130 species and subspecific taxa. We present an overview of past floristic literature pertaining to desmid species distribution in New England and enrich the current checklist by 65 new records for the state of Maine. Additionally, eight taxa could not be confidently matched to known species, suggesting they may represent heretofore undescribed taxonomic entities. This, coupled with the fact that desmids can serve as water quality indicators, suggests that the desmid diversity in northern New England merits further attention and research.

Ecological status of shallow Lake Gorbacz (NE Poland) in its final stage before drying up

Abstract The article assesses the ecological status of shallow Gorbacz Lake (NE Poland) in the last stage before complete drying up. For last few years hydrological regime of the lake catchment has been changed dramatically which was caused by functioning nearby peat mine and longer autumn drought periods for following years. Progressing macrophytes succession leaded complete emergent macrophytes overgrowth of the lake beginning from 2000. The analyses include records of previous samples and data for morphology, water quality, phytoplankton, zooplankton and macrophytes. The trophic status of Gorbacz Lake was verified compare to the previous studies. The results indicate that even with minimum amount of water Gorbacz Lake itself still keeps its dystrophic character with increasing of water color and of DOC, biogenic substances, chlorophyll a concentrations. Humic State Index (HSI) and hydrochemical dystrophy index (HDI) confirm the dystrophic status of the lake with values 71.3 and 76.2 respectively. Both typical phytoplankton representatives of eutrophic and dystrophic waters were recorded. Very high diversity of desmids in the telmatoplankton, indicates the observed process of shallowing in the reservoir. Planktonic crustacean fauna was represented by small filtrators. Rotifera community was strongly dominated by Trichocerca simonei. The article concludes with the main causes of the observed changes and some future remarks for the lake state.

Diversity of desmids in three Thai peat swamps

Three peat swamps situated in the southern part of Thailand were investigated for their desmid flora in relation to a number of physical and chemical habitat parameters. Altogether, 99 species were encountered belonging to 22 genera. 30 species are new records for the Thai desmid flora. Laempagarung peat swamp showed the highest diversity (45 species), followed by Maikhao peat swamp (32 species) and Jud peat swamp (25 species). Despite its relatively low species richness, Jud swamp appeared to house a number of rare taxa, e.g., Micrasterias subdenticulata var. ornata, M. suboblonga var. tecta and M. tetraptera var. siamensis which can be considered Indo-Malaysian endemics. Differences in composition of the desmid flora between the three peat swamps are discussed in relation to environmental conditions.

Diversity and geographic distribution of desmids and other coccoid green algae

Taxonomic diversity of desmids and other coccoid green algae is discussed in relation to different species concepts. For want of unambiguous criteria about species delimitation, no reliable estimations of global species richness can be given. Application of the biological species concept is seriously hampered by lack of sexual reproduction in many species. Molecular analyses demonstrated cases of close affiliation between morphologically highly different taxa and, contrary, examples of little relationship between morphologically similar taxa. Despite the fact that desmids and chlorococcal algae, because of their microbial nature, can be readily distributed, cosmopolitan species are relatively scarce. The geographic distribution of some well-recognizable morphospecies is discussed in detail. Of some species a recent extension of their area could be established, e.g., in the desmids Micrasterias americana and Euastrum germanicum, and in the chlorococcaleans Desmodesmus perforatus and Pediastrum simplex.

Application of desmid diversity in assessing the water quality of 12 freshwater resources in Thailand

Desmids from 12 freshwater resources in the northern part of Thailand were investigated during 2002 to 2003. A total of 91 taxa were found. They belonged to 17 genera: Actinotaenium, Spirotaenia, Netrium, Gonatozygon, Pleurotaenium, Closterium, Euastrum, Micrasterias, Cosmarium, Cosmocladium, Stuarastrum, Staurodesmus, Xanthidium, Teilingia, Spondylosium, Hyalotheca and Desmidium. The water qualities in all the water resources were classified as oligotrophic to meso-eutrophic by trophic status. The taxa that could possibly be used as bioindicators of trophic state were Staurastrum gutwinskii, Spondylosium pandurifoemae, Cosmarium capitulum, C. mediosrobiculatum var. egranutum, S. tortum, Closterium gracile var. elongatum, C. kuetzingii and Closterium dianae var. dianae. The most frequently found taxa were Staurastrum limneticum var. burmense, S. tetracerum var. tetraerum, Pleurotaenium trabecula, Closterium ehrenbergii var. ehrenbergii and C. kuetzingii. The rare taxa in this study were Actinotaenium sp. Spirotaenia condensata, Pleurotaenium burmense var. dacchense and Micrasterias apiculata. Forty-one taxa of desmids were identified as new records for Thailand.

A Checklist Of Desmids In Nigeria

The paper presents a checklist of diversity and distribution of desmid flora in Nigeria. Samples of desmids were collected by means of 55-micrometer mesh plankton net from different locations. There was a high diversity of desmids. A total of 478 taxa are listed in this report. These are categorized into 27 genera, 273 species, 176 varieties and 29 forma. Five of the genera belong to saccoderm desmids while 22 are placoderm desmids. Of all the genera, Cosmarium was dominant with 91 taxa, followed by Closterium with 84 taxa and Staurastrum with 83 taxa. The cosmopolitan taxa were Closterium lunula, Cl. setaceum, Cosmarium monodii, Desmidium swartzii and Pleurotaenium trabecula. Keywords: Taxonomy, desmids, phytogeography, tropics. (Global Journal of Pure and Applied Sciences: 2002 8(2): 223-238)

Structural Characteristics and Adaptations of Desmid Communities

SUMMARY (1) Nearly 400 samples containing desmids, previously referred to three groups by the application of a classification program, were ordinated on the basis of their desmid species composition. (2) In alkaline, open water habitats, as eutrophication increased, there was a decrease in desmid diversity, and an increase in the proportion of planktonic forms. (3) Submerged fen-hollows were dominated, in relatively eutrophic sites, by small desmids with short generation times, whereas in relatively oligotrophic sites, larger desmids with longer generation times prevailed. The greatest desmid diversity occurred in the middle part of the trophic range; this is explained by a greater niche differentiation resulting from frequent fluctuations in nutrient concentrations in the habitat. (4) In emergent fen habitats, the desmid diversity decreased with decreasing moisture content and rising acidity. The relative contribution of omniradiate forms with a small surface: volume ratio increased. (5) The ecological significance of these characteristics, and the relationship between genera: species ratio and habitat are discussed.

Wisconsin desmids. III. Desmid community composition and distribution in relation to lake type and water chemistry

This investigation summarizes quantitative data on the generic composition of the euplankton and aufwuchs desmid communities of 61 Wisconsin lakes, and analyzes the information with respect to 1) the role of the various genera in terms of frequency, density, and relative importance, 2) the suitability of various lake types for harboring desmid communities, and 3) the relationships between chemical parameters and desmid distribution. The generaStaurastrum, Cosmarium, andClosterium are of wide occurrence, appear to play major roles in the communities of all lake types, and are the most tolerant of varying chemical conditions. Most euplankton genera are of importance only in acid bogs, but aufwuchs genera generally are more widely distributed. Both the euplankton and the aufwuchs communities appear to be composed of 1–4 desmid assemblages, each with a differing range of importance values. Based on biological criteria, acid bogs appear to be the most suitable lake type for harboring desmid communities and calcareous spring ponds the least suitable type. High generic diversity of desmids appears to be correlated with low conductivity, calcium and alkalinity levels, pH values of 5.1–7.0, and the presence of free CO2. The evidence attending various hypotheses concerning water chemistry and desmid distribution appears contradictory, and further studies are needed to help clarify the situation.