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Richard E. Triemer - One of the best experts on this subject based on the ideXlab platform.
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Multigene analyses of photosynthetic euglenoids and new family, phacaceae (euglenales)
Journal of Phycology, 2010Co-Authors: Jong Im Kim, Woongghi Shin, Richard E. TriemerAbstract:Bayesian and maximum-likelihood (ML) analyses of the combined multigene data (nuclear SSU rDNA, and plastid SSU and LSU rDNA) were conducted to evaluate the phylogeny of photosynthetic euglenoids. The combined data set consisted of 108 strains of photosynthetic euglenoids including a colorless sister taxon. Bayesian and ML analyses recovered trees of almost identical topology. The results indicated that photosynthetic euglenoids were divided into two major clades, the Euglenaceae clade (Euglena, Euglenaria, Trachelomonas, Strombomonas, Monomorphina, Cryptoglena, Colacium) and the Phacaceae clade (Phacus, Lepocinclis, Discoplastis). The Euglenaceae clade was monophyletic with high support and subdivided into four main clades: the Colacium, the Strombomonas and Trachelomonas, the Cryptoglena and Monomorphina, and the Euglena and Euglenaria clades. The genus Colacium was positioned at the base of the Euglenaceae and was well supported as a monophyletic lineage. The loricate genera (Strombomonas and Trachelomonas) were located at the middle of the Euglenaceae clade and formed a robust monophyletic lineage. The genera Cryptoglena and Monomorphina also formed a well-supported monophyletic clade. Euglena and the recently erected genus Euglenaria emerged as sister groups. However, Euglena proxima branched off at the base of the Euglenaceae. The Phacaceae clade was also a monophyletic group with high support values and subdivided into three clades, the Discoplastis, Phacus, and Lepocinclis clades. The genus Discoplastis branched first, and then Phacus and Lepocinclis emerged as sister groups. These genera shared a common characteristic, numerous small discoid chloroplasts without pyrenoids. These results clearly separated the Phacaceae clade from the Euglenaceae clade. Therefore, we propose to limit the family Euglenaceae to the members of the Euglena clade and erect a new family, the Phacaceae, to house the genera Phacus, Lepocinclis, and Discoplastis.
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PHYLOGENY OF THE EUGLENOID LORICATE GENERA Trachelomonas AND STROMBOMONAS (EUGLENOPHYTA) INFERRED FROM NUCLEAR SSU AND LSU rDNA(1).
Journal of phycology, 2008Co-Authors: Ionel Ciugulea, Stacy Brosnan, María A. Nudelman, Richard E. TriemerAbstract:Previous studies using the nuclear SSU rDNA and partial LSU rDNA have demonstrated that the euglenoid loricate taxa form a monophyletic clade within the photosynthetic euglenoid lineage. It was unclear, however, whether the loricate genera Trachelomonas and Strombomonas were monophyletic. In order to determine the relationships among the loricate taxa, SSU and LSU nuclear rDNA sequences were obtained for eight Strombomonas and 25 Trachelomonas strains and combined in a multigene phylogenetic analysis. Conserved regions of the aligned data set were used to generate maximum-likelihood (ML) and Bayesian phylogenies. Both methods recovered a strongly supported monophyletic loricate clade with Strombomonas and Trachelomonas species separated into two sister clades. Taxa in the genus Strombomonas sorted into three subclades. Within the genus Trachelomonas, five strongly supported subclades were recovered in all analyses. Key morphological features could be attributed to each of the subclades, with the major separation being that all of the spine-bearing taxa were located in two sister subclades, while the more rounded, spineless taxa formed the remaining three subclades. The separation of genera and subclades was supported by 42 distinct molecular signatures (33 in Trachelomonas and nine in Strombomonas). The morphological and molecular data supported the retention of Trachelomonas and Strombomonas as separate loricate genera.
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PHYLOGENY OF THE EUGLENALES BASED UPON COMBINED SSU AND LSU RDNA SEQUENCE COMPARISONS AND DESCRIPTION OF DISCOPLASTIS GEN. NOV. (EUGLENOPHYTA)
Journal of Phycology, 2006Co-Authors: Richard E. Triemer, Woongghi Shin, Eric W. Linton, Alejandra Nudelman, Anna Monfils, Matthew S. Bennett, Stacy BrosnanAbstract:A Bayesian analysis, utilizing a combined data set developed from the small subunit (SSU) and large subunit (LSU) rDNA gene sequences, was used to resolve relationships and clarify generic boundaries among 84 strains of plastid-containing euglenophytes representing 11 genera. The analysis produced a tree with three major clades: a Phacus and Lepocinlis clade, a Discoplastis clade, and a Euglena, Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena clade. The majority of the species in the genus Euglena formed a well-supported clade, but two species formed a separate clade near the base of the tree. A new genus, Discoplastis, was erected to accommodate these taxa, thus making the genus Euglena monophyletic. The analysis also supported the monophyly of Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena, which formed two subclades sister to the Euglena clade. Colacium, Trachelomonas, and Strombomonas, all of which produce copious amounts of mucilage to form loricas or mucilaginous stalks, formed a well-supported lineage. Our analysis supported retaining Strombomonas and Trachelomonas as separate genera. Monomorphina and Cryptoglena formed two well-supported clades that were sister to the Colacium, Trachelomonas, and Strombomonas clade. Phacus and Lepocinclis, both of which have numerous small discoid chloroplasts without pyrenoids and lack peristaltic euglenoid movement (metaboly), formed a well-supported monophyletic lineage that was sister to the larger Euglena through Cryptoglena containing clade. This study demonstrated that increased taxon sampling, multiple genes, and combined data sets provided increased support for internal nodes on the euglenoid phylogenetic tree and resolved relationships among the major genera in the photosynthetic euglenoid lineage.
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MORPHOLOGICAL SEPARATION OF THE EUGLENOID GENERA Trachelomonas AND STROMBOMONAS (EUGLENOPHYTA) BASED ON LORICA DEVELOPMENT AND POSTERIOR STRIP REDUCTION1
Journal of Phycology, 2005Co-Authors: Stacy Brosnan, Patrick J. P. Brown, Mark A. Farmer, Richard E. TriemerAbstract:Since the separation of the Trachelomonas Ehrenberg subgroup "Saccatae" into a new genus, Strombomonas Deflandre (1930), there has been some question as to its validity. Deflandre's separation was based entirely on characteristics of the lorica, including the shape of the lorica, the lack of a distinctive collar, possession of a tailpiece, lack of ornamentation, and the ability of Strombomonas species to aggregate particles on the surface of the lorica. Recent molecular analyses indicated that the loricate taxa {Trachelomonas and Strombomonas) formed a single monophyletic clade; however, the phylogenetic relationship of Strombomonas to Trachelomonas remains unclear because only two Strombomonas taxa have been sequenced to date. In this study, we evaluated the monophyly of the loricate genera using two sets of morphological characters, lorica development and pellicle strip reduction. Lorica development in Strombomonas occurred from the anterior of the cell to the posterior, forming a shroud over the protoplast. In Trachelomonas, a layer of mucilage was excreted over the entire protoplast, followed by creation of the collar at the anterior end. Taxa from both genera underwent exponential strip reduction at the anterior and posterior poles. In Strombomonas only one reduction was visible in the anterior pole, whereas in most Trachelomonas species two reductions were visible. Likewise, Strombomonas species possessed two whorls of strip reduction in the posterior end compared with a single whorl of strip reduction in Trachelomonas species. These morphological characters support the separation of Trachelomonas and Strombomonas as distinct genera.
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12 Phylogeny of the euglenoid loricate genera Trachelomonas and strombomonas based on morphological and molecular data
Journal of Phycology, 2003Co-Authors: Stacy Brosnan, Richard E. TriemerAbstract:Since the separation of the Trachelomonas subgroup “Saccatae” into a new genus, Strombomonas Deflandre (1930), there has been some question as to its validity. Deflandre's separation was based on morphological characteristics such as the shape of the lorica, lack of a distinctive collar, possession of a tailpiece, lack of ornamentation, and ability to aggregate particles on the lorica. Recent molecular analyses indicated that the loricate taxa were monophyletic, but few species have been sampled. The LSU rDNA from eleven Strombomonas and thirty-eight Trachelomonas species was sequenced to evaluate the monophyly of the two genera. Bayesian and maximum-likelihood analyses found one monophyletic clade for each genus. The Trachelomonas clade was weakly supported, but had five strongly supported subclades. Morphological characters, such as lorica development and pellicle strip reduction, also supported separation of the genera. Lorica development in Strombomonas occurred from the anterior of the cell to the posterior, forming a shroud over the protoplast whereas in Trachelomonas, a layer of mucilage was excreted over the entire protoplast, followed by creation of the collar at the anterior end. Taxa from both genera underwent exponential strip reduction at the anterior and posterior poles. In Strombomonas, only one reduction was visible in the anterior pole, while in most Trachelomonas species, two reductions were visible. Likewise, Strombomonas species possessed two whorls of strip reduction in their posterior end compared to a single whorl of strip reduction in Trachelomonas species. The combined morphological and molecular data support the retention of Trachelomonas and Strombomonas as separate genera.
Konrad Wołowski - One of the best experts on this subject based on the ideXlab platform.
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Trachelomonas volzii vs T . dubia (Euglenophyceae)—one or two separate species? Study on similarities and differences of the species
Phytotaxa, 2018Co-Authors: Małgorzata Poniewozik, Konrad Wołowski, Jolanta PiątekAbstract:This study concerns the two species Trachelomonas volzii and T . dubia which were examined for similarities and dissimilarities of their loricae and monads organization. We specifically focused on the key features of both species that were originally used to separate one from the other: annular thickening at the base of collar and dimensions and ornamentation of loricae. Loricae of specimens were examined by light and scanning electron microscopy and the results were compared with the literature data describing these taxa and reported occurrences in the world. The species together with their varieties and forms do not appear to have strong characteristics distinguishing them, rather the variability observed fits natural phenotypic changes. Based on evidence from this study, we recommend combining these two taxa and propose T . volzii as the single taxon. We also examined a set of varieties of original T . volzii since the species contained several varieties that were almost identical in relation to lorica structure and occurrence. As a result of these observations, we propose the following varieties: Trachelomonas volzii var. volzii as a nominative variety, T . volzii var. australis , T . volzii var. sulcata , T . volzii var. inflata , T . volzii var. acidophila . Furthermore, we propose reclassifying some taxa and the new combinations such as: T . dubia var. ornata to T . volzii var. ornata and T . dubia var. colliundulata to T . volzii var. colliundulata . In our opinion, T . dubia fo. acuminata should be included with the species T . hexangulata due to its unique, hexagonal shaped lorica.
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Morphological Variability of Loricae in Trachelomonas caudata Complex (Euglenophyta)
Cryptogamie Algologie, 2016Co-Authors: Konrad Wołowski, Małgorzata Poniewozik, Josef JuráňAbstract:Abstract This study documented lorica ultrastructure variation in Corresponding author: and related taxa from natural populations. On that basis, inaccuracies in the taxonomic system of euglenoid Trachelomonas are pointed out. Loricae of T. caudata and taxa very similar to it were examined by light and scanning electron microscopy and by energy-dispersive X-ray spectroscopy (EDS). The latter observations showed similarity of chemical composition between loricae of different putative taxa, with silicon and iron as the main components, and the absence of a chemical element considered to be a very important component of trachelomonad envelopes - manganese. All observed morphotypes were classified in one complex based upon envelope configuration, and the “caudatae complex” was established. Our morphological analyses led us to conclude that f. pseudocaudata of T. caudata should be subsumed in the typical form or treated as a synonym of T. caudata, as the morphological differences between them are within the ty...
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Colacium Minimum (Euglenophyta), A New Epiphytic Species For Asia
Polish Botanical Journal, 2015Co-Authors: Konrad Wołowski, Kritsana Duangjan, Yuwadee PeerapornpisalAbstract:AbstractColacium minimum Fott & Komárek, known so far from a few localities in Central Europe (Czech Republic), is reported here for the first time from Asia (Thailand). This epiphytic species was found growing on eight taxa of loricated euglenoids. The process of surface colonization of Trachelomonas Ehrenb. and Strombomonas Deflandre taxa by C. minimum in natural populations is briefly discussed and originally documented using LM and SEM.
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Development of Trachelomonas species (Euglenophyta) during blooming of Planktothrix agardhii (Cyanoprokaryota)
Annales de Limnologie - International Journal of Limnology, 2014Co-Authors: Magdalena Grabowska, Konrad WołowskiAbstract:This paper reports data on a community of Trachelomonas species (Euglenophyta) occurring during Planktothrix agardhii bloom formation in a shallow, highly eutrophic dam reservoir. The results come from a long-term study of Siemianowka Dam Reservoir, located on the upper Narew River (NE Poland). From April to October 2007, 132 alga taxa were identified, including 32 Trachelomonas taxa, 23 of which are new for the reservoir; of those, three are first records for Poland: T. armata (Ehrenberg) Stein var. heterospina Swirenko, T. atomaria Skvortzov var. minor Hortobagi and T. minima Drez uepolski. One variety, T. curta var. pappilata Wooowski, is described as new for science. The ultrastructural details of Trachelomonas species are illustrated. The highest number of Trachelomonas taxa was recorded in August in the shore zone of the re- servoir. At the end of summer 2007, the conspicuous development of P. agardhii (Gomont) Anagnostidis et Komarek, caused a rapid decrease of Trachelomonas biomass due to lower water transparency and the oxygen concentration. In addition, a decline in the Trachelomonas taxa and biomass was associated with a decrease of water temperature. The negative impact of extracellular microcystin on the Trachelomonas development requires further study.
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New taxa of loricate euglenoids Strombomonas and Trachelomonas from Thailand
Polish Botanical Journal, 2013Co-Authors: Kritsana Duangjan, Konrad WołowskiAbstract:Five new species and one new variety of loricate euglenoid taxa were discovered in Thailand: Strombomonas starmachii Duangjan & Wolowski, S. chiangmaiensis Duangjan, Trachelomonas peerapornpisalii Duangjan & Wolowski, T. thailandicus Duangjan & Wolowski, T. reticulato-spinifera Duangjan and T. hystrix var. paucispinosa Prowse. We propose to raise the variety to species level (T. paucispinosa (Prowse) Duangjan & Wolowski, stat. et comb. nov.). The morphology and fine lorica ultra- structure of the species are described. All taxa are documented by SEM images and some by LM micrographs.
Stacy Brosnan - One of the best experts on this subject based on the ideXlab platform.
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PHYLOGENY OF THE EUGLENOID LORICATE GENERA Trachelomonas AND STROMBOMONAS (EUGLENOPHYTA) INFERRED FROM NUCLEAR SSU AND LSU rDNA(1).
Journal of phycology, 2008Co-Authors: Ionel Ciugulea, Stacy Brosnan, María A. Nudelman, Richard E. TriemerAbstract:Previous studies using the nuclear SSU rDNA and partial LSU rDNA have demonstrated that the euglenoid loricate taxa form a monophyletic clade within the photosynthetic euglenoid lineage. It was unclear, however, whether the loricate genera Trachelomonas and Strombomonas were monophyletic. In order to determine the relationships among the loricate taxa, SSU and LSU nuclear rDNA sequences were obtained for eight Strombomonas and 25 Trachelomonas strains and combined in a multigene phylogenetic analysis. Conserved regions of the aligned data set were used to generate maximum-likelihood (ML) and Bayesian phylogenies. Both methods recovered a strongly supported monophyletic loricate clade with Strombomonas and Trachelomonas species separated into two sister clades. Taxa in the genus Strombomonas sorted into three subclades. Within the genus Trachelomonas, five strongly supported subclades were recovered in all analyses. Key morphological features could be attributed to each of the subclades, with the major separation being that all of the spine-bearing taxa were located in two sister subclades, while the more rounded, spineless taxa formed the remaining three subclades. The separation of genera and subclades was supported by 42 distinct molecular signatures (33 in Trachelomonas and nine in Strombomonas). The morphological and molecular data supported the retention of Trachelomonas and Strombomonas as separate loricate genera.
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PHYLOGENY OF THE EUGLENALES BASED UPON COMBINED SSU AND LSU RDNA SEQUENCE COMPARISONS AND DESCRIPTION OF DISCOPLASTIS GEN. NOV. (EUGLENOPHYTA)
Journal of Phycology, 2006Co-Authors: Richard E. Triemer, Woongghi Shin, Eric W. Linton, Alejandra Nudelman, Anna Monfils, Matthew S. Bennett, Stacy BrosnanAbstract:A Bayesian analysis, utilizing a combined data set developed from the small subunit (SSU) and large subunit (LSU) rDNA gene sequences, was used to resolve relationships and clarify generic boundaries among 84 strains of plastid-containing euglenophytes representing 11 genera. The analysis produced a tree with three major clades: a Phacus and Lepocinlis clade, a Discoplastis clade, and a Euglena, Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena clade. The majority of the species in the genus Euglena formed a well-supported clade, but two species formed a separate clade near the base of the tree. A new genus, Discoplastis, was erected to accommodate these taxa, thus making the genus Euglena monophyletic. The analysis also supported the monophyly of Colacium, Trachelomonas, Strombomonas, Monomorphina, and Cryptoglena, which formed two subclades sister to the Euglena clade. Colacium, Trachelomonas, and Strombomonas, all of which produce copious amounts of mucilage to form loricas or mucilaginous stalks, formed a well-supported lineage. Our analysis supported retaining Strombomonas and Trachelomonas as separate genera. Monomorphina and Cryptoglena formed two well-supported clades that were sister to the Colacium, Trachelomonas, and Strombomonas clade. Phacus and Lepocinclis, both of which have numerous small discoid chloroplasts without pyrenoids and lack peristaltic euglenoid movement (metaboly), formed a well-supported monophyletic lineage that was sister to the larger Euglena through Cryptoglena containing clade. This study demonstrated that increased taxon sampling, multiple genes, and combined data sets provided increased support for internal nodes on the euglenoid phylogenetic tree and resolved relationships among the major genera in the photosynthetic euglenoid lineage.
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MORPHOLOGICAL SEPARATION OF THE EUGLENOID GENERA Trachelomonas AND STROMBOMONAS (EUGLENOPHYTA) BASED ON LORICA DEVELOPMENT AND POSTERIOR STRIP REDUCTION1
Journal of Phycology, 2005Co-Authors: Stacy Brosnan, Patrick J. P. Brown, Mark A. Farmer, Richard E. TriemerAbstract:Since the separation of the Trachelomonas Ehrenberg subgroup "Saccatae" into a new genus, Strombomonas Deflandre (1930), there has been some question as to its validity. Deflandre's separation was based entirely on characteristics of the lorica, including the shape of the lorica, the lack of a distinctive collar, possession of a tailpiece, lack of ornamentation, and the ability of Strombomonas species to aggregate particles on the surface of the lorica. Recent molecular analyses indicated that the loricate taxa {Trachelomonas and Strombomonas) formed a single monophyletic clade; however, the phylogenetic relationship of Strombomonas to Trachelomonas remains unclear because only two Strombomonas taxa have been sequenced to date. In this study, we evaluated the monophyly of the loricate genera using two sets of morphological characters, lorica development and pellicle strip reduction. Lorica development in Strombomonas occurred from the anterior of the cell to the posterior, forming a shroud over the protoplast. In Trachelomonas, a layer of mucilage was excreted over the entire protoplast, followed by creation of the collar at the anterior end. Taxa from both genera underwent exponential strip reduction at the anterior and posterior poles. In Strombomonas only one reduction was visible in the anterior pole, whereas in most Trachelomonas species two reductions were visible. Likewise, Strombomonas species possessed two whorls of strip reduction in the posterior end compared with a single whorl of strip reduction in Trachelomonas species. These morphological characters support the separation of Trachelomonas and Strombomonas as distinct genera.
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12 Phylogeny of the euglenoid loricate genera Trachelomonas and strombomonas based on morphological and molecular data
Journal of Phycology, 2003Co-Authors: Stacy Brosnan, Richard E. TriemerAbstract:Since the separation of the Trachelomonas subgroup “Saccatae” into a new genus, Strombomonas Deflandre (1930), there has been some question as to its validity. Deflandre's separation was based on morphological characteristics such as the shape of the lorica, lack of a distinctive collar, possession of a tailpiece, lack of ornamentation, and ability to aggregate particles on the lorica. Recent molecular analyses indicated that the loricate taxa were monophyletic, but few species have been sampled. The LSU rDNA from eleven Strombomonas and thirty-eight Trachelomonas species was sequenced to evaluate the monophyly of the two genera. Bayesian and maximum-likelihood analyses found one monophyletic clade for each genus. The Trachelomonas clade was weakly supported, but had five strongly supported subclades. Morphological characters, such as lorica development and pellicle strip reduction, also supported separation of the genera. Lorica development in Strombomonas occurred from the anterior of the cell to the posterior, forming a shroud over the protoplast whereas in Trachelomonas, a layer of mucilage was excreted over the entire protoplast, followed by creation of the collar at the anterior end. Taxa from both genera underwent exponential strip reduction at the anterior and posterior poles. In Strombomonas, only one reduction was visible in the anterior pole, while in most Trachelomonas species, two reductions were visible. Likewise, Strombomonas species possessed two whorls of strip reduction in their posterior end compared to a single whorl of strip reduction in Trachelomonas species. The combined morphological and molecular data support the retention of Trachelomonas and Strombomonas as separate genera.
Amadeu M.v.m. Soares - One of the best experts on this subject based on the ideXlab platform.
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Inorganic composition of the envelopes of Trachelomonas Ehr. (Euglenophyta)
Acta Oecologica, 2003Co-Authors: Mário Jorge Pereira, Ulisses Miranda Azeiteiro, Fernando Gonçalves, Amadeu M.v.m. SoaresAbstract:The Trachelomonas genus comprehends unicellular organisms and contains a highly metabolic euglenoid cell surrounded by a particular structure, the lorica, with shape, morphology and dimensions characteristic of each taxon (species, variety). This organic matrix may present a significant mineralization. The elementary lorica composition was microanalysed by energy dispersive spectrometry in scanning electron microscopy. The inorganic component found in materials obtained from natural environments may represent more than 50% of the total weight of the lorica, which is normally above 25%. In the inorganic fraction, iron is the major element (1-49%) of the total weight of the lorica. Sulphur, P, Cl, Na, K, Ca, Mg, Si, Al, Cu, Ni and Zn constitute the remaining inorganic components.
Patricia L. Walne - One of the best experts on this subject based on the ideXlab platform.
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Strombomonas and Trachelomonas species (Euglenophyta) from south-eastern USA
European Journal of Phycology, 2007Co-Authors: Konrad Wołowski, Patricia L. WalneAbstract:A biogeographical and taxonomic study on Strombomonas and Trachelomonas, which are often abundant in polluted environments, was undertaken in south-eastern USA. Light and scanning electron microscope analysis allowed the identification of 68 taxa, among them five Strombomonas and 63 Trachelomonas. All are documented with original SEM and LM micrographs. Twenty-seven Trachelomonas taxa are reported as new from this region. Variability in lorica microstructure is demonstrated for T. curta var. curta, T. pusilla var. punctata, T. rotunda, T. hispida var. coronata and T. scabra var. scabra from natural habitats. Physicochemical parameters for water quality at the collection sites are reported.
