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The article discusses the achievements and transitions which the periodical has underwent after 15 years of its launch. It highlights that under the leadership of editor-in-chief Denis H. Lynn and Portia Holt the periodical has incorporated electronic submission of research papers and manuscripts from authors. The periodical will continue with recognition of eminent authors for their contributions towards the journal with the William Trager Award for Outstanding Paper every year.

Based on both morphological and molecular information, two new euplotid genera Apodiophrys n. g. and Heterodiophrys n. g. are described in the present paper. Apodiophrys n. g. is defined as sculptured Diophryinae with bipartite adoral zone; frontoventral cirri arranged in Diophrys-pattern; marginal cirri located in two clearly separated groups. Heterodiophrys n. g. is recognizable by the combination of Diophrys-like frontoventral cirri and the unique structure of several marginal cirri that are arranged in a long row. The type species for both new genera, Apodiophrys ovalis n. sp. and Heterodiophrys zhui n. sp., collected from southern China sea, are described. The small subunit rRNA (SSU rRNA) gene sequences for both new taxa are determined. Phylogenetic analyses based on these data indicate that Apodiophrys is most closely related to Paradiophrys, which then clusters with Uronychia species. Thus, Apodiophrys–Paradiophrys is separated from other typical Diophrys-like genera in the SSU rRNA gene trees. The new genus Heterodiophrys is basal to the sister group of Diophrys–Diophryopsis, hence belongs to the “core” Diophrys-complex. [ABSTRACT FROM AUTHOR]

The table of contents for the November 2007 issue of "The Journal of Eukaryotic Microbiology" is presented.

Presents an overview on the taxonomy and phylogeny of protists. Kinds of biotic interactions; Role of protists in support of all life on the planet Earth; Influence of protists in restricting bacterial and fungal growth in such habitats; Role of anoxic protists in altering Earth's environment chemically.

Highlights the important trends in the field of protistology. Controversy over the origin of the eukaryotic cells; Emergence of complete genome sequencing in the field of parasitology; Role of protists in global carbon and sulfur cycles.

Presents the study redescribing the sarcocysts of Sarcocystis rileyi (Apicomplexa: Sarcocystidae). Identification of the intermediate hosts for Sarcocystis rileyi; Assessment of the types of specimens for the study; Investigation of the sections of pectoral muscles.

The table of contents for the November 2006 issue of "The Journal of Eukaryotic Microbiology" is presented.

Presents the table of contents to the November 2005 issue of "The Journal of Eukaryotic Microbiology."

This revision of the classification of eukaryotes follows that of Adl et al., 2012 [J. Euk. Microbiol. 59(5)] and retains an emphasis on protists. Changes since have improved the resolution of many nodes in phylogenetic analyses. For some clades even families are being clearly resolved. As we had predicted, environmental sampling in the intervening years has massively increased the genetic information at hand. Consequently, we have discovered novel clades, exciting new genera and uncovered a massive species level diversity beyond the morphological species descriptions. Several clades known from environmental samples only have now found their home. Sampling soils, deeper marine waters and the deep sea will continue to fill us with surprises. The main changes in this revision are the confirmation that eukaryotes form at least two domains, the loss of monophyly in the Excavata, robust support for the Haptista and Cryptista. We provide suggested primer sets for DNA sequences from environmental samples that are effective for each clade. We have provided a guide to trophic functional guilds in an appendix, to facilitate the interpretation of environmental samples, and a standardized taxonomic guide for East Asian users. [ABSTRACT FROM AUTHOR]

ABSTRACT S pathidiopsis and P lacus are the only two genera within the family Placidae. The family has been placed in the class Prostomatea and order Prorodontida because its members have somatic monokinetids with a radial transverse ribbon, a straight non-overlapping postciliary ribbon, and anteriorly directed non-overlapping kinetodesmal fibril, an apical cytostome lacking specialized oral cilia, a brosse, and toxicysts. To confirm the stability of this placement, ultrastructural morphology and small subunit rRNA gene sequences of S pathidiopsis socialis, S pathidiopsis buddenbrocki, and P lacus striatus were determined. These data were combined with information from other ciliates, and phylogenetic trees were generated using maximum-likelihood and maximum-parsimony methods. The analyses confirmed the family Placidae to be a monophyletic group in the Prostomatea with the Placidae a sister group to a C ryptocaryon + C oleps + P rorodon clade. [ABSTRACT FROM AUTHOR]

ABSTRACT. Using nine new taxa and statistical inferences based on morphological and molecular data, we analyze the evolution within the class Colpodea. The molecular and cladistic analyses show four well-supported clades: platyophryids, bursariomorphids, cyrtolophosidids, and colpodids. There is a widespread occurrence of homoplasies, affecting even conspicuous morphological characteristics, e.g. the inclusion of the micronucleus in the perinuclear space of the macronucleus. The most distinct changes in the morphological classification are the lack of a basal divergence into two subclasses and the split of the cyrtolophosidids into two main clades, differing mainly by the presence vs. absence of an oral cavity. The most complex clade is that of the colpodids. We partially reconcile the morphological and molecular data using evolutionary systematics, providing a scenario in which the colpodids evolved from a Bardeliella-like ancestor and the genus Colpoda performed an intense adaptive radiation, giving rise to three main clades: Colpodina n. subord., Grossglockneriina, and Bryophryina. Three new taxa are established: Colpodina n. subord., Tillinidae n. fam., and Ottowphryidae n. fam. Colpodean evolution and classification are far from being understood because sequences are lacking for most species and half of their diversity is possibly undescribed. [ABSTRACT FROM AUTHOR]

A membranous closing apparatus shuts the lorica opening in disturbed tintinnids of six genera belonging to four families. The homology of the apparatuses is investigated, using data from the literature and Mediterranean tintinnids studied in vivo and by scanning electron microscopy. Morphological and functional similarities indicate that the foldable closing apparatus is not only a synapomorphy of the genera Codonella (Codonellidae) and Dictyocysta (Dictyocystidae), as suggested 80 years ago, but also of Codonaria (Codonellidae) and Codonellopsis (Codonellopsidae). In Codonaria, Codonella, and Dictyocysta, the apparatuses merge posteriorly into membranous lorica sacs, which probably represent homologous structures. The diagnoses of these genera are improved according to the new findings. The close relationship of Codonella, Codonellopsis, and Dictyocysta is also inferred from small subunit rRNA phylogenies and the ultrastructure of the capsules. It contradicts the current lorica-based classification of the tintinnids. The assumption that the diaphragm-like apparatus in the genera Salpingacantha and Salpingella is not homologous to the foldable ones in the genera mentioned above is supported by molecular and cytological features. [ABSTRACT FROM AUTHOR]

This study provides, for the first time, sequence data for the protozoan flagellates Crithidia bombi and Crithidia mellificae (Kinetoplastea: Trypanosomatidae). We amplified the partial sequences of the small subunit ribosomal RNA ( SSU rRNA), glycosomal glyceraldehyde phosphate dehydrogenase ( gGAPDH), cytochrome b ( Cyt b), and the complete internal transcribed spacer region 1 ( ITS1) of the ribosomal RNA gene region for 66 clones of C. bombi from Switzerland and Alaska. Furthermore, we sequenced the same stretch of SSU rRNA and gGAPDH for one isolate of C. mellificae from Switzerland. All four molecular markers classified the C. bombi samples into two distinct lineages A and B. Both lineages were found in the two sampling locations. Variation within lineages was small or non-existing. Sequence differences between lineages were 1.64% for SSU rRNA, 4.36% for gGAPDH, and 12.02% for Cyt b. The ITS1-sequences of lineages A and B have diverged so much that no alignment was possible. With regard to ITS1, we additionally found fragment length polymorphism (variation in microsatellite repeat numbers) as well as nucleotide diversity within each lineage. Furthermore, the sequences of SSU rRNA and gGAPDH of C. mellificae were different from both lineages of C. bombi. The separation of lineages A and B, based on sequence differences and phylogenetic reconstruction, is so pronounced as to characterize two species of “ C. bombi.” We propose to retain C. bombi for the more common lineage A and suggest the name Crithidia expoeki n. sp. for lineage B. [ABSTRACT FROM AUTHOR]

In the course of a large-scale global survey of mycetozoans, amoeboid organisms that form fruiting bodies, a new species of Acrasis was discovered from several subtropical locales in Hawaii, Australia, Bermuda, and South Africa. We isolated four strains from dead, still attached, plant material, and one strain from attached bark of a tree. Each isolate forms simple uniseriate multicellular fruiting bodies typically consisting of two bottle-shaped, basal stalk cells and a chain of <20 spores. The isolate from Bermuda often forms dichotomous simple branches, each consisting of <10 spores. Amoebae from these new isolates are limax with eruptive pseudopodial formation and display rapid locomotion—characters indicative of amoebae in the excavate taxon Heterolobosea. These isolates form simpler fruiting bodies than is typical of the well-known Acrasis rosea. Although in the original description, A. rosea is known to form uniseriate fruiting bodies similar to our isolates, A. rosea isolates typically form more complex fruiting structures along side simple ones, but never strictly simple ones. Nuclear-encoded 18S rRNA gene phylogenies demonstrate that our five isolates form a highly supported clade that is sister to A. rosea. Given the differences both in gene sequences and fruiting body morphology between our isolates and A. rosea, we propose the new species, Acrasis helenhemmesae n. sp. [ABSTRACT FROM AUTHOR]

We sequenced the small subunit (SSU) rRNA and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) genes of two trypanosomes isolated from the Brazilian snakes Pseudoboa nigra and Crotalus durissus terrificus. Trypanosomes were cultured and their morphometrical and ultrastructural features were characterized by light microscopy and scanning and transmission electron microscopy. Phylogenetic trees inferred using independent or combined SSU rRNA and gGAPDH data sets always clustered the snake trypanosomes together in a clade closest to lizard trypanosomes, forming a strongly supported monophyletic assemblage (i.e. lizard–snake clade). The positioning in the phylogenetic trees and the barcoding based on the variable V7–V8 region of the SSU rRNA, which showed high sequence divergences, allowed us to classify the isolates from distinct snake species as separate species. The isolate from P. nigra is described as a new species, Trypanosoma serpentis n. sp., whereas the isolate from C. d. terrificus is redescribed here as Trypanosoma cascavelli. [ABSTRACT FROM AUTHOR]

Presents a correction to the article "Highly Divergent Actins from Karyorelictean, Heterotrich, and Litostome Ciliates," by Oanh T. P. Kim, Kei Yura, Nobuhiro Go and Terue Harumoto, previously published in the "Journal of Eukaryotic Microbiology."

Presents a corrected reprint of an article previously published in a 2004 issue of the periodical "The Journal of Eukaryotic Microbiology".

The planktonic ciliate Balanion masanensis n. sp. is described from living cells, from cells prepared by quantitative protargol staining (QPS), scanning electron microscopy (SEM), and transmitted electron microscopy (TEM) preparations, and the sequence of its nuclear small subunit rDNA (SSU rDNA) is reported. This species is almost ovoid with a flattened anterior oral region when the cells are alive and stained. The flattened anterior region of a living cell often forms a dome with the perimeter receded in a groove, and this region is easily inflated or depressed. In SEM photos, a brosse of six to nine monokinetids (or possibly three to five dikinetids) was observed inside the circumoral dikinetids. In TEM photos, circumoral microtubular ribbons were observed below the oral cilia, which along with the oral flaps were 8–16 μm in length. The cytostome is a slight funnel-like central depression on the flattened anterior end. The morphological characteristics of this ciliate are identical to those of the genus Balanion (Order Prorodontida). The ranges (and mean±standard deviation) of cell length, cell width, and oral diameter of living cells (n=23–26) were 27–43 μm (35.2±4.6), 25–32 μm (28.6±2.3), and 25–30 μm (27.6±1.3), respectively, while those of the QPS-stained specimens (n=70) were 23–37 μm (30.6±3.5), 26–35 μm (30.7±2.2), and 26–33 μm (29.5±1.5), respectively. Forty-six to 55 somatic kineties (SKs) were equally spaced around the cell body and extended from the oral to near the posterior regions with 24–50 monokinetids per kinety. Each kinetid bore a cilium 2.8–7.2 μm long. A caudal cilium (ca 14 μm long) arose on the posterior end. The single ellipsoid macronucleus is 6.8–13.4 × 6.8–10.5 μm, accompanied by a single micronucleus (2.0–2.8 × 1.5–2.5 μm) visible only in QPS specimens. Because, the cell size, the number of SKs, and the number of kinetosomes per SK of this ciliate were much greater than those of Balanion comatum and Balanion planctonicum, the only two Balanion species so far reported, we have established B. masanensis n. sp. When properly aligned, the sequence of the SSU rDNA of B. masanensis n. sp. (GenBank Accession No. AM412525) was approximately 9% different from that of Coleps hirtus (Colepidae, Prorodontida) and 12% different from that of Prorodon teres (Prorodontidae, Prorodontida). [ABSTRACT FROM AUTHOR]

The genus Sappinia, a taxon of free-living amoebae with trophozoites that typically have two closely appressed nuclei, contains two named species, Sappinia pedata, the type species, and S. diploidea. The amoebae of both species are essentially identical according to the literature. The two species are distinguished by S. pedata having a standing amoeba stage, incorrectly interpreted as a cyst, and S. diploidea having sessile, bicellular cysts. Using four isolates of S. pedata collected from around the world, we present detailed light micrographic illustrations of all stages of its life cycle. We confirm that the standing amoeba lacks a cell wall. In two isolates of S. pedata, there are bicellular cysts indistinguishable from those of S. diploidea. Using sequence data from the nuclear small subunit ribosomal RNA gene, we conclude that S. pedata and the published neotype of S. diploidea are congeneric but not conspecific. The genus branches within Thecamoebidae. Sequencing of the actin gene confirms the inclusion of Sappinia in Thecamoebidae. Resolving the taxonomy of Sappinia is gaining importance because it has recently been attributed as an opportunistic human pathogen. [ABSTRACT FROM AUTHOR]

The article provides a brief summary of the research presented at the 9th International Workshops on Opportunistic Protists which was held as a joint meeting with the 57th annual meetings of the International Society of Protistologists in Lisbon, Portugal from June 20 to 24, 2006. The author mentions the different topics in the research including the keynote speakers and themes of the workshops.

Examination of mucus discharged from the blowhole of Atlantic bottlenose dolphin ( Tursiops truncatus) at Marine Life Oceanarium, Gulfport, Mississippi, and false killer whale ( Pseudorca crassidens) and Atlantic bottlenose dolphin at SeaWorld Orlando, Orlando, Florida, using live observations and protargol impregnation revealed mixed infections of Kyaroikeus cetarius and two new species. Planilamina n. gen. is characterized by a C-shaped argentophilic band located along the laterally flattened margin of cell and extending from the cell apex to subposterior cone-shaped podite; a deep oral cavity containing one short preoral kinety, two circumoral kineties, seven to 13 infundibular kineties, and a cytostome; a broadly funnel-shaped cytopharynx reinforced by argentophilic fibers but without nematodesmata; closely packed postoral kinetofragments set in a pocket located anterior left of the podite; and somatic kineties as a right field closely situated at the right surface and a left field bordering the anterior left margin of the oral cavity. The type species for the genus, Planilamina ovata n. sp., is distinguished from its sister species Planilamina magna n. sp. by the following characteristics: body size (28–65 × 20–43 μm vs. 57–90 × 40–63 μm), number of right field kineties (38–55 vs. 79–99), and position of the anterior end of the leftmost kinety in the right somatic field (anterior one-third vs. mid-body). The morphogenesis of Planilamina ovata is similar to that of K. cetarius. The diagnosis of Kyaroikeidae is emended to accommodate the new genus. [ABSTRACT FROM AUTHOR]

A new heterotrophic flagellate ( Andalucia godoyi n. gen. n. sp.) is described from soil. Earlier preliminary 18S rRNA analyses had indicated a relationship with the phylogenetically difficult-to-place jakobid Jakoba incarcerata. Andalucia godoyi is a small (3–5 μm) biflagellated cell with a ventral feeding groove. It has tubular mitochondrial cristae. There are two major microtubular roots (R1, R2) and a singlet root associated with basal body 1 (posterior). The microtubular root R1 is associated with non-microtubular fibres “I,”“B,” and “A,” and divides in two parts, while R2 is associated with a “C” fibre. These structures support the anterior portion of the groove. Several features of A. godoyi are characteristic of jakobids: (i) there is a single dorsal vane on flagellum 2; (ii) the C fibre has the jakobid multilaminate substructure; (iii) the dorsal fan of microtubules originates in very close association with basal body 2; and (iv) there is no “R4” microtubular root associated with basal body 2. Morphological analyses incorporating the A. godoyi data strongly support the monophyly of all jakobids. Our 18S rRNA phylogenies place A. godoyi and J. incarcerata as a strong clade, which falls separately from other jakobids. Statistical tests do not reject jakobid monophyly, but a specific relationship between Jakoba libera and J. incarcerata and/or A. godoyi is rejected. Therefore, we have established a new genus Andalucia n. gen. with the type species Andalucia godoyi n. sp., and transfer Jakoba incarcerata to Andalucia as Andalucia incarcerata n. comb. [ABSTRACT FROM AUTHOR]

To investigate the relationship between the Japanese Paramecium bursaria host and its symbiont, we studied the effect of a host cell-free extract on carbon fixation and photosynthate release of the symbiont. The host extract enhanced symbiotic algal carbon fixation about 3-fold at an increased concentration; however, release of photosynthate hardly changed. Since the enhancing effect was not affected by elimination of carbon dioxide from the host extract, the existence of a host factor that stimulates algal carbon fixation was made clear. The host factor is a heat-stable, low molecular weight substance. In relation to the pH dependence, the extract improved carbon fixation at acidic and neutral pH and showed almost no effect at pH 9.0. Therefore, the stimulation of carbon fixation by the host factor is unlikely to be caused by intracellular pH change. The extract also improved carbon fixation of several Chlorella species, symbiotic and free-living, and apparently exhibited no species specificity. Therefore, the host seems to regulate the photosynthesis of the symbiont via a specific compound. [ABSTRACT FROM AUTHOR]

An understanding of large-scale eukaryotic evolution is beginning to crystallise, as molecular and morphological data demonstrate that eukaryotes fall into six major groups. However, there are several taxa of which the affinities are yet to be resolved, and for which there are only either molecular or morphological data. One of these is the amoeboid flagellate Mastigamoeba invertens. This organism was originally misidentified and studied as a pelobiont using molecular data. We present its first light microscopical and ultrastructural characterisation. We demonstrate that it does not show affinities to the amoebozoan pelobionts, because unlike the pelobionts, it has a double basal body and two flagellar roots, a classical Golgi stack, and a large branching double membrane-bound organelle. Phylogenetic analyses of small subunit ribosomal RNA suggest an affinity with the apusomonads, when a covariotide correction for rate heterogeneity is used. We suggest that previous molecular results have been subject to artefacts from an insufficient correction for rate heterogeneity. We propose a new name for the taxon, Breviata anathema; and the unranked, apomorphy-based name “Breviates” for Breviata and its close relatives. [ABSTRACT FROM AUTHOR]

This revision of the classification of unicellular eukaryotes updates that of Levine et al. (1980) for the protozoa and expands it to include other protists. Whereas the previous revision was primarily to incorporate the results of ultrastructural studies, this revision incorporates results from both ultrastructural research since 1980 and molecular phylogenetic studies. We propose a scheme that is based on nameless ranked systematics. The vocabulary of the taxonomy is updated, particularly to clarify the naming of groups that have been repositioned. We recognize six clusters of eukaryotes that may represent the basic groupings similar to traditional “kingdoms.” The multicellular lineages emerged from within monophyletic protist lineages: animals and fungi from Opisthokonta, plants from Archaeplastida, and brown algae from Stramenopiles. [ABSTRACT FROM AUTHOR]

Focuses on dinoflagellate Stoeckeria algicida from the Coastal Waters off Southern Korea. Morphology and small subunit ribosomal DNA gene sequence; Remarks on culturing behavior; Morphological characteristics.

Studies Holosticha hamulata and Holosticha heterofoissneri, two urostylid ciliates from intertidal sediments of the Yellow Sea. Morphometric data; Occurrence and ecology; Comparison between populations of Holostica heterofoissneri; Location of the contractile vacuole as a taxonomic feature.

Describes Protospathidium serpens and Protospathidium fraterculum, two species based on different resting cyst morphology. Biogeographic pattern of the dorsal brush and cyst wall morphology; Total number of brush dikinetids; Discussion of resting cyst morphology with respect to alpha-taxonomy and ciliate diversity.

Focuses on the identification and localization of a protein immunologically related to caltractin in the myonemes and membranelles of the heterotrich ciliate Stentor coeruleus. Contractile properties of the myonemes; Localization of myonemes in intact cells.

Reports that abrupt increase in ultraviolet sensitivity at late log-phase of growth in Paramecium tetraurelia. Clonal life cycle of Paramecium; Developmental process of differentiation and aging that advances as the cell cycle rotates.

Focuses on potentially algal-lytic marine bacteria strongly associated with the toxic dinoflagellate Alexandrium catenella. Purification of phenotypically different cultivable bacterial colonies; Recovery of symbiotic characteristics.

Presents a study of cell size and shape, nuclear changes and the ciliary pattern during conjugation of Protospathidium serpens using protargol impregnation and morphometry. Percentage of transparent non-feeding specimens; Observation of a definite season in wild ciliate populations; Changes occurring in post-dividers, exconjugants, and excysting cells with endomixis.

Describes the bacterial endosymbionts or pathogens of free-living amebaef. Habitats of free-living amebae; Interaction of amebae with other microorganisms in their environment; Relationship of bacteria and amebae; Association of amebae with intracellular bacterial pathogens.

Reports on the description of Strombidinopsis jeokjo n. sp. by researchers from Seoul, South Korea. Examination on the morphology and small subunit ribosomal DNA gene sequence; Population of the species in the genus Strombidinopsis in coastal and oceanic waters; Success of the researchers on the collection and culturing of Strombidinopsis sp.

Studies Phyllopharyngean ciliates and their group I introns by researchers from Amherst, Massachusetts. Examination on the molecular phylogeny of Phyllopharyngea; Analysis on the small subunit ribosomal DNA sequences of the ciliate; Evaluation on the monophyly of the ciliate class and the relationships among subclasses.

Studies phylogenetic position of species in the genera Anoplophrya, Plagiotoma, and Nyctotheroides (Phylum Ciliophora), endosymbiotic ciliates of annelids and anurans. Astomes derived from hymenostome-like ancestors; Relationship of clevelandellids and metopid and caenomorphid ciliates.

Studies symbiotic innovation in the oxymonad Streblomastix strix. Order of epibiotic bacteria; Adherence of bacteria to oxymonad host.

Studies diversity of insect trypanosomatids assessed from the spliced leader RNA and 5S rRNA genes and intergenic regions. Isolates assigned by morphology to different genera; Molecular phylogenetic data.

Studies morphologic and genetic variability in the marine planktonic ciliate Laboea strobila. Ontogenesis of the ciliate; Morphological investigations; Data from ecological literature.

Describes the sequence analysis of the six new members of the never in mitosis A (NIMA)-related kinase (CNK) family in Chlamydomonas. Identification of CNK 1-6; Relationship of the six new genes to known NIMA-related proteins;Role of NIMA family kinase in cell cycle progression.