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DNA sequences were analyzed for three groups of species from the Lepocinclis genus (L. acus‐like, L. oxyuris‐like, and L. tripteris‐like) along with cellular morphology. Phylogenetic analyses were based on nuclear SSU rDNA, LSU rDNA, and plastid‐encoded LSU rDNA. DNA sequences were obtained from species available in culture collections (L. acus SAG 1224‐1a and UTEX 1316) and those isolated directly from the environment in Poland (48 isolates), resulting in 79 new sequences. The obtained phylogenetic tree of Lepocinclis included 27 taxa, five of which are presented for the first time (L. convoluta, L. gracillimoides, L. longissima, L. pseudospiroides, and L. torta) and nine taxonomically verified and described. Based on morphology, literature data, and phylogenetic analyses, the following species were distinguished: in the L. acus‐like group, L. longissima and L. acus; in the L. tripteris‐like group, L. pseudospiroides, L. torta, and L. tripteris; in the L. oxyuris‐like group, L. gracillimoides, L. oxyuris var. oxyuris, and L. oxyuris var. helicoidea. For all verified species, diagnostic descriptions were emended, nomenclatural adjustments were made, and epitypes were designated. [ABSTRACT FROM AUTHOR]

Although Lepocinclis ovum is recognized as a cosmopolitan and common species, and Lepocinclis globulus is the type species of the genus Lepocinclis, their correct identification is nearly impossible. The reason is that over 30 morphologically similar taxa appear in the literature, but no good diagnostic features exist to distinguish amongst them. Using environmental sampling and nuclear SSU rDNA sequencing, we delimited species within the group of Lepocinclis ovum‐like taxa. Morphological and molecular features were analyzed for taxa isolated from Poland and six cultured strains from algal collections. In the case of environmental sampling, DNA was obtained from a small number of cells (20–400) isolated with a micropipette without setting up laboratory cultures (52 isolates), and phylogenetic analyses were based on the variation in nSSU rDNA. Apart from L. ovum and L. globulus, 13 other species were distinguished and four taxa (Lepocinclis conica comb. nov., L. fominii comb. nov., L. gracilicauda comb. nov., and L. pseudofominii nom. nov.) had their taxonomic ranks changed. For all verified species, diagnostic descriptions were emended and epitypes designated. The only exception was L. ovum, for which the epitype was questioned and thus, a new candidate for the epitype was suggested for future adoption. [ABSTRACT FROM AUTHOR]

Photosynthetic euglenids acquired chloroplasts by secondary endosymbiosis, which resulted in changes to their mode of nutrition and affected the evolution of their morphological characters. Mapping morphological characters onto a reliable molecular tree could elucidate major trends of those changes. We analyzed nucleotide sequence data from regions of three nuclear-encoded genes (nSSU, nLSU, hsp90), one chloroplast-encoded gene (cpSSU) and one nuclear-encoded chloroplast gene ( psbO) to estimate phylogenetic relationships among 59 photosynthetic euglenid species. Our results were consistent with previous works; most genera were monophyletic, except for the polyphyletic genus Euglena, and the paraphyletic genus Phacus. We also analyzed character evolution in photosynthetic euglenids using our phylogenetic tree and eight morphological traits commonly used for generic and species diagnoses, including: characters corresponding to well-defined clades, apomorphies like presence of lorica and mucilaginous stalks, and homoplastic characters like rigid cells and presence of large paramylon grains. This research indicated that pyrenoids were lost twice during the evolution of phototrophic euglenids, and that mucocysts, which only occur in the genus Euglena, evolved independently at least twice. In contrast, the evolution of cell shape and chloroplast morphology was difficult to elucidate, and could not be unambiguously reconstructed in our analyses. [ABSTRACT FROM AUTHOR]

Euglena sanguinea (Ehrenberg 1831) was one of the first green euglenoid species described in the literature. At first, the species aroused the interest of researchers mainly due to the blood-red color of its cells, which, as it later turned out, is not a constant feature. Complicated chloroplast morphology, labeled by Pringsheim as the 'peculiar chromatophore system', made the correct identification of the species difficult, which is the reason why, throughout the 20th century, new species resembling E. sanguinea were continually being named due to a lack of suitable diagnostic features to distinguish E. sanguinea. Interest in E. sanguinea has returned in recent years, following findings that the species can produce ichthyotoxins. This was followed by the need to classify E. sanguinea correctly, which was achieved through the verification of morphological and molecular data for all species similar to E. sanguinea. As the result of the analysis, the number of species sharing some morphological similarities with E. sanguinea could be reduced from 12, as described in the literature, to four, with established epitypes and updated diagnostic descriptions. The most important diagnostic features included: the presence of mucocysts (i.e., whether they were visible before and/or after staining), the number of chloroplasts, the size of the double-sheathed pyrenoids, and the presence of the large paramylon grain in the vicinity of the stigma. Moreover, sequence analysis revealed the presence of unusually long SSU r DNA sequences in E. sanguinea. Previously, SSU r DNA sequences of such length were known to be present in primary osmotrophic euglenoids. [ABSTRACT FROM AUTHOR]

The establishment of epitypes (together with the emended diagnoses) for three species of Euglenaria Karnkowska, E. W. Linton et Kwiatowski [ Eu. anabaena (Mainx) Karnkowska et E. W. Linton; Eu. caudata (Hübner) Karnkowska et E. W. Linton; and Eu. clavata (Skuja) Karnkowska et E. W. Linton] and two species of Euglena Ehrenberg [ E. granulata (Klebs) Schmitz and E. velata Klebs] was achieved due to literature studies, verification of morphological diagnostic features (cell size, cell shape, number of chloroplasts, the presence of mucocysts), as well as molecular characters (SSU rDNA). Now all these species are easy to identify and distinguish, despite their high morphological similarity, that is, spindle-shaped (or cylindrically spindle-shaped) cells and parietal, lobed chloroplasts with a single pyrenoid, accompanied by bilateral paramylon caps located on both sides of the chloroplast. E. granulata is the only species in this group that has spherical mucocysts. E. velata is distinguished by the largest cells (90-150 μm) and has the highest number of chloroplasts (>30). Eu. anabaena has the fewest chloroplasts (usually 3-6), and its cells are always (whether the organism is swimming or not) spindle-shaped or cylindrically spindle-shaped, in contrast to the cells of Eu. clavata, which are club-shaped (clavate) while swimming and only after stopping change to resemble the shape of a spindle or a cylindrical spindle; Eu. clavata has numerous chloroplasts (15-20). Eu. caudata is characterized by asymmetrical spindle-shaped (fusiform) cells, that is, with an elongated rear section and a shorter front section; the number of chloroplasts normally ranges from 7 to 15. [ABSTRACT FROM AUTHOR]

Morphological and molecular studies, as well as original literature reexamination, necessitate establishment of five Euglena species with a single axial, stellate chloroplast [ Euglena viridis (O. F. Müller) Ehrenberg 1830 , Euglena pseudoviridis  Chadefaud 1937 , Euglena stellata  Mainx 1926 , Euglena pseudostellata sp. nov., and Euglena cantabrica  Pringsheim 1956 ], three species with two chloroplasts ( Euglena geniculata Dujardin ex Schmitz 1884 , Euglena chadefaudii  Bourrelly 1951 , and Euglena pseudochadefaudii sp. nov.), and one species with three chloroplasts ( Euglena tristella  Chu 1946 ). The primary morphological features, allowing distinction of the considered species are the presence and the shape of mucocysts, as well as the number of chloroplasts. Spherical mucocysts occur in E. cantabrica and E. geniculata, while spindle-shaped mucocysts are present in E. stellata, E. pseudostellata, E. chadefaudii, E. pseudochadefaudii, and E. tristella. No mucocysts are observed in E. viridis and E. pseudoviridis. Two new species ( E. pseudochadefaudii sp. nov. and E. pseudostellata sp. nov.) differ from the respective species, E. chadefaudii and E. stellata, only at the molecular level. Molecular signatures and characteristic sequences are designated for nine distinguished species. Emended diagnoses for all and delimitation of epitypes for seven species (except E. viridis and E. tristella) are proposed. [ABSTRACT FROM AUTHOR]

Eighteen new 16S rDNA and 16 new 18S rDNA sequences from 24 strains, representing 23 species of photoautotrophic euglenoids, were obtained in nearly their entire length. Maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses were performed on separate data (39 sequences of 16S rDNA and 58 sequences of 18S rDNA), as well as on combined data sets (37 sequences). All methods of sequence analysis gave similar results in those cases in which the clades received substantial support. However, the combined data set produced several additional well-supported clades, not encountered before in the analyses of green euglenoids. There are three main well-defined clades (A, B/C/D, and G) on trees from the combined data set. Clade G diverges first, while clades A and B/C/D form sister groups. Clade A consists of Euglena species sensu stricto and is divided into three sub-clades (A1, A2, and A3). Clade A3 (composed of E. deses and E. mutabilis) branches off first; then, two sister clades emerge: A1 (composed of E. viridis-like species) and A2 (consisting of E. agilis and E. gracilis species). Clade B/C/D consists of the Strombomonas, Trachelomonas, Cryptoglena, Monomorphina, and Colacium genera. Clade G comprises Phacus and Lepocinclis, as well as the Discoglena species of Euglena, with Discoglena branching off first, and then Phacus and Lepocinclis emerging as sister groups. [ABSTRACT FROM AUTHOR]

Euglena sanguinea (Ehrenberg 1831) was one of the first green euglenoid species described in the literature. At first, the species aroused the interest of researchers mainly due to the blood-red color of its cells, which, as it later turned out, is not a constant feature. Complicated chloroplast morphology, labeled by Pringsheim as the 'peculiar chromatophore system', made the correct identification of the species difficult, which is the reason why, throughout the 20th century, new species resembling E. sanguinea were continually being named due to a lack of suitable diagnostic features to distinguish E. sanguinea. Interest in E. sanguinea has returned in recent years, following findings that the species can produce ichthyotoxins. This was followed by the need to classify E. sanguinea correctly, which was achieved through the verification of morphological and molecular data for all species similar to E. sanguinea. As the result of the analysis, the number of species sharing some morphological similarities with E. sanguinea could be reduced from 12, as described in the literature, to four, with established epitypes and updated diagnostic descriptions. The most important diagnostic features included: the presence of mucocysts (i.e., whether they were visible before and/or after staining), the number of chloroplasts, the size of the double-sheathed pyrenoids, and the presence of the large paramylon grain in the vicinity of the stigma. Moreover, sequence analysis revealed the presence of unusually long SSU r DNA sequences in E. sanguinea. Previously, SSU r DNA sequences of such length were known to be present in primary osmotrophic euglenoids. [ABSTRACT FROM AUTHOR]

The establishment of epitypes (together with the emended diagnoses) for three species of Euglenaria Karnkowska, E. W. Linton et Kwiatowski [ Eu. anabaena (Mainx) Karnkowska et E. W. Linton; Eu. caudata (Hübner) Karnkowska et E. W. Linton; and Eu. clavata (Skuja) Karnkowska et E. W. Linton] and two species of Euglena Ehrenberg [ E. granulata (Klebs) Schmitz and E. velata Klebs] was achieved due to literature studies, verification of morphological diagnostic features (cell size, cell shape, number of chloroplasts, the presence of mucocysts), as well as molecular characters (SSU rDNA). Now all these species are easy to identify and distinguish, despite their high morphological similarity, that is, spindle-shaped (or cylindrically spindle-shaped) cells and parietal, lobed chloroplasts with a single pyrenoid, accompanied by bilateral paramylon caps located on both sides of the chloroplast. E. granulata is the only species in this group that has spherical mucocysts. E. velata is distinguished by the largest cells (90-150 μm) and has the highest number of chloroplasts (>30). Eu. anabaena has the fewest chloroplasts (usually 3-6), and its cells are always (whether the organism is swimming or not) spindle-shaped or cylindrically spindle-shaped, in contrast to the cells of Eu. clavata, which are club-shaped (clavate) while swimming and only after stopping change to resemble the shape of a spindle or a cylindrical spindle; Eu. clavata has numerous chloroplasts (15-20). Eu. caudata is characterized by asymmetrical spindle-shaped (fusiform) cells, that is, with an elongated rear section and a shorter front section; the number of chloroplasts normally ranges from 7 to 15. [ABSTRACT FROM AUTHOR]

Euglena sanguinea (Ehrenberg 1831) was one of the first green euglenoid species described in the literature. At first, the species aroused the interest of researchers mainly due to the blood-red color of its cells, which, as it later turned out, is not a constant feature. Complicated chloroplast morphology, labeled by Pringsheim as the "peculiar chromatophore system", made the correct identification of the species difficult, which is the reason why, throughout the 20th century, new species resembling E. sanguinea were continually being named due to a lack of suitable diagnostic features to distinguish E. sanguinea. Interest in E. sanguinea has returned in recent years, following findings that the species can produce ichthyotoxins. This was followed by the need to classify E. sanguinea correctly, which was achieved through the verification of morphological and molecular data for all species similar to E. sanguinea. As the result of the analysis, the number of species sharing some morphological similarities with E. sanguinea could be reduced from 12, as described in the literature, to four, with established epitypes and updated diagnostic descriptions. The most important diagnostic features included: the presence of mucocysts (i.e., whether they were visible before and/or after staining), the number of chloroplasts, the size of the double-sheathed pyrenoids, and the presence of the large paramylon grain in the vicinity of the stigma. Moreover, sequence analysis revealed the presence of unusually long SSU rDNA sequences in E. sanguinea. Previously, SSU rDNA sequences of such length were known to be present in primary osmotrophic euglenoids., (© 2013 Phycological Society of America.)