Aerial Sorocarp Development By the Aggregative Ciliate,Sorogena Stoianovitchae*

SYNOPSIS. Sorogena stoianovitchae Bradbury & Olive, an epiphytic ciliate found in various parts of the world, has a trophic stage that feeds on members of the ciliate genus Colpoda. When grown in the presence of the food ciliate, it multiplies rapidly. When the cells become abundant they aggregate at the water surface on inserted plant fragments or floating pollen grains, the sides of culture dishes, or on floating films such as those deposited by bacteria or pollen grains. an aggregate mounds up and becomes ensheathed above the water level, after which the mass of cells called a sorogen rises aerially at the apex of a stalk deposited at its base. the tapering, noncellular stalk consists of a conspicuously furrowed sheath that encloses a mucilaginous matrix. At completion of stalk development the cells of the sorogen become encysted. the sorocysts are commonly discharged by fracturing of the drying sorus. Alternating light and dark conditions are required for sorocarp development.     

Phylogenetic position of Sorogena stoianovitchae and relationships within the class Colpodea (Ciliophora) based on SSU rDNA sequences

The ciliate Sorogena stoianovitchae, which can form a multicellular fruiting body, has been classified based upon its ultrastructure and morphology: the oral and somatic infraciliature of S. stoianovitchae most closely resemble those of members of the order Cyrtolophosidida in the class Colpodea. We characterized the small subunit ribosomal DNA (SSU rDNA) gene sequence from S. stoianovitchae and compared this sequence with those from representatives of all ciliate classes. These analyses placed S. stoianovitchae as either sister to members of the class Nassophorea or Colpodea. In an in-group analysis, including all SSU rDNA sequences from members of the classes Nassophorea and Colpodea and representatives of appropriate outgroups, S. stoianovitchae was always sister to Platyophrya vorax (class Colpodea, order Cyrtolophosidida). However, our analyses failed to support the monophyly of the class Colpodea. Instead, our data suggest that there are essentially three unresolved clades: (1) the class Nassophorea; (2) Bresslaua vorax, Colpoda inflata, Pseudoplatyophrya nana, and Bursaria truncatella (class Colpodea); and (3) P. vorax and S. stoianovitchae (class Colpodea).     

Fine Structure of the Feeding Stage of A Sorogenic Ciliate, Sorogena Stoianovitchae Gen. N., Sp. N.

SYNOPSIS. A new species of kinetophragminophoran ciliate, collected from dried vegetation and capable of forming an aerial sorocarp, is described and named Sorogena stoianovitchae gen. n., sp. n. This ciliate is a voracious predator that feeds on species of Colpoda , and, when the latter is depleted in numbers, aggregates to forms sorogens. Each sorogen rises into the air from the surface of the water, forming a secreted stalk with a sorus of cysts at its apex. the feeding stage of the ciliate resembles an Enchelys in that it has an apical, slit-like mouth surrounded by a lip, a somewhat dorso-ventrally flattened body, and meridional kineties. Its length ranges from 40–75 μm and width from 23–55 μm. It has a typical rhabdos type of cytopharynx, but no specialized oral ciliature. the somatic kineties are formed of rows of paired kinetosomes with associated microfibrils, the arrangement of which differs a little from that of other ciliates of this subclass. Sorogena has tentatively been placed in the order Haptorida although it lacks toxicysts, recognizable mucocysts, and clavate cilia. Its unique life cycle and some of the details of its fine structure indicate differences between Sorogena and other haptorids so profound that a new family, SOROGENIDAE, is created for it. the type species (PNG76-73) was collected on dry figs at the Wau Ecology Institute, Papua New Guinea.     

Morphology, morphometrics, and molecular characterization of Bryophrya gemmea n. sp. (Ciliophora, Colpodea): implications for the phylogeny and evolutionary scenario for the formation of oral ciliature in the order Colpodida

We studied the morphology, morphometry, resting, and reproductive cysts, as well as the molecular phylogeny of Bryophrya gemmea n. sp., a colpodid ciliate that was discovered in ephemeral puddles in Idaho, northwest United States. This new species is distinguished from congeners by the irregularly pentagonal adoral organelles, four to five vestibular kineties, the single micronucleus, and one to three rows of brightly refractive protuberant interkinetal cortical granules to the right of the preoral suture. Resting cysts have two distinct membranes and an outer mucous coat. As typical for most colpodids, reproduction occurs in division cysts but details of ontogenesis are unknown. The 18S rRNA gene sequence shows only weak support for the phylogenetic relationship between Bryophrya and the bryophryid genus Notoxoma previously inferred from morphologic characters. Further, our molecular phylogenies classify bryophryids rather basal within the order Colpodida, not supporting ordinal status suggested by morphologists. Based on molecular data and morphologic characters, the colpodid genus Ilsiella is removed from the family Marynidae and placed in a new family, Ilsiellidae. Considering the molecular data, an evolutionary scenario for the formation of colpodid oral structures from a cyrtolophosidid ancestor through a bryophryid intermediate is proposed.     

Analysis of fruiting body development in the aggregative ciliate Sorogena stoianovitchae (Ciliophora, Colpodea)

The fruiting body-forming ciliate Sorogena stoianovitchae is a protist that is multicellular in one stage of its life cycle. When nutrient levels are depleted, a number of Sorogena cells aggregate beneath the water surface to form an aerial fruiting body. Based on morphologies and the inhibition of protein synthesis, fruiting body development is divided into five distinct stages: (1) aggregation before sunrise, (2) compact aggregation after sunrise, (3) secretion of mucous matrix, (4) stalk-elongation, and (5) completion of the fruiting-body. In the aggregation stage, the cells were trapped in a matrix material that stained orange with 4',6-diamino-2-phenylindole (DAPI), but differed from the mucous matrix in the later stage. A short interruption of the dark period, at 6-8 h after the onset of dark, inhibited fruiting body development. Irrespective of the length of the dark period (10-16 h), the cells remained in the aggregation stage until the beginning of the light period. Therefore, an uninterrupted dark period of more than 8 h is critical for the initial aggregation of cells, but subsequent development is triggered by light.     

Morphology and morphometry of Bresslauides pratensis n. sp., a new soil ciliate (Ciliophora, Colpodea) from Turkey

A new colpodid ciliate, Bresslauides pratensis n. sp., was discovered in soil from a meadow field in Turkey. Its morphology was investigated using live observation, protargol impregnation, silver nitrate impregnation, and scanning electron microscopy. The new species differs from the congeners by the following combination of features: the cell size in vivo is about 135-180 μm × 130-160 μm; the body has an almost circular outline with a conspicuous bulge on the ventral side; the somatic cilia are arranged in about 105 densely spaced, sigmoidal kineties; a diagonal groove extends to the left cell side, terminating in a pronounced postoral sack; one almost globular macronucleus and usually two globular micronuclei; the oral structures occupy almost the anterior half of the cell and comprise a distally elongated right polykinetid and a crescentic left oral polykinetid, both restricted to the vestibulum; on average 12 vestibular, 31 postoral, and 55 left oral kineties. Based on the morphological data, it was concluded that B. pratensis is a well-outlined and distinctive member of the genus Bresslauides. Additionally, the most recent molecular data on the order Colpodida and genera Colpoda, Bresslaua, and Bresslauides are briefly discussed.     

Morphological and Molecular Characterization of a New Protist Family, Sandmanniellidae n. fam. (Ciliophora, Colpodea), with Description of Sandmanniella terricola n. g., n. sp. from the Chobe Floodplain in Botswana

ABSTRACT. Sandmanniella terricola n. g., n. sp. was discovered in soil from the Chobe floodplain, Botswana, southern Africa. Its morphology and 18S rDNA gene sequence were studied with standard methods. Sandmanniella terricola is very likely an adversity strategist because it reaches peak abundances 6–12 h after rewetting the soil and maintains trophic food vacuoles with undigested bacteria in the resting cyst, a highly specific feature suggested as an indicator for an adversity life strategy. Possibly, the energy of the stored food vacuoles is used for reproduction and support of the cyst wall. Morphologically, Sandmanniella terricola is inconspicuous, having a size of only 50 × 40 μm and a simple, ellipsoidal shape. The main characteristics of the genus are a colpodid silverline pattern; a perioral cilia condensation; a flat, dish-shaped oral cavity, in the centre of which originates a long, conical oral basket resembling that of certain nassulid ciliates; and a vertically oriented left oral polykinetid composed of brick-shaped adoral organelles. This unique mixture of features and the gene sequence trees, where Sandmanniella shows an isolated position, suggest establishing a new family, the Sandmanniellidae n. fam., possibly related to the families Colpodidae or Bryophryidae. The curious oral basket provides some support for the hypothesis of a common ancestor of colpodid and nassulid ciliates.     

Morphology and infraciliature of a new marine ciliate Euplotidium smalli n. sp. with description of a new genus,Paraeuplotidium n. g. (Ciliophora,Euplotida)

The morphology and infraciliature of a new hypotrichous ciliate, Euplotidium smalli n. sp., isolated from eutrophic coastal water in Korea, were observed in living cells and investigated using the protargol impregnation technique. This new ciliate bears 13-14 frontoventral cirri, 7 transverse cirri, and 5-6 dorsal kineties. Neither left marginal cirrus nor caudal cirrus is present. The new species differs from the related species, Euplotidium agitatum Noland, 1937 in the different number of frontoventral and transverse cirri and different body shape. With the exception of Euplotidium agitatum, the known species of the genus Euplotidium Noland, 1937 with the presence of left marginal cirrus are assigned to a new genus, Paraeuplotidium n. g. Diagnosis of Paraeuplotidium is: Gastrocirrhidae with funnel-shaped buccal cavity; with frontoventral and transverse cirri; left marginal cirrus present. Paraeuplotidium itoi (Ito, 1958) n. comb. is designated here the type species. Four additional species are included: Paraeuplotidium psammophilus (Vacelet, 1961) n. comb., Paraeuplotidium arenarium (Magagnini & Nobili, 1964) n. comb., Paraeuplotidium helgae (Hartwig, 1980) n. comb., and Paraeuplotidium prosaltans (Tuffrau, 1985) n. comb. An improved generic diagnosis of Euplotidium is suggested based on morphology and infraciliature characters: marine hypotrichs with a funnel-shaped buccal cavity; with frontoventral and transverse cirri; neither left marginal cirrus nor caudal cirri present.     

Lekking in fallow deer

Bradbury & Gibson (1983) define leks as 'assemblies of adult males which females visit solely for the purpose of copulation'. Although a relatively rare breeding system, lekking has been reported in a wide variety of taxa, including fireflies, butterflies, fish, frogs, manakins and grouse (see Loiselle & Barlow, 1978; Wittenberger, 1978; Bradbury, 1981; Lederhouse, 1982; Oring, 1982). Lek-breeding mammals include one bat (Bradbury, 1977), several antelope (see below) and possibly walrus (Fay, Ray & Kibal'chich, 1984). Nevertheless, the adaptive significance of lek-breeding is still poorly understood (Bradbury & Gibson, 1983).     

Morphogenesis of the marine spirotrichous ciliate, Trachelostyla pediculiformis (Cohn, 1866) (Ciliophora, Stichotrichia), with consideration of its phylogenetic position

The cortical development during binary fission of the relatively poorly known stichotrich ciliate, Trachelostyla pediculiformis (Cohn, 1866) Borror, 1972, found in coastal waters near Qingdao, China, was investigated using the protargol impregnation method. The morphogenetic process reveals some pretty unusual characteristics, which do not follow the Oxytricha-pattern: (1) the parental oral apparatus is entirely renewed from an oral primordium formed de novo in the proter; (2) in the proter, the parental undulating membranes are not involved in the formation of the newly formed oral primordium; both undulating membrane-anlagen (UM-anlage) and frontoventral-transverse cirral anlagen (FVT-anlagen) develop from the oral primordium in the proter; (3) the dorsal kineties (DK) are generated in a unique way, that is, in both dividers, two separate groups of DK-anlagen develop in the right- and left-most DK, generate all the DK and evolve to replace the old structures; (4) three caudal cirri are formed at the posterior ends of three right-most dorsal kinety anlagen; (5) eight frontal, five ventral and five transverse cirri are derived from six streaks, namely, the UM-anlage and 5 FVT-anlagen; the cirri are segregated from these anlagen in the pattern 1:3:3:3:4:4 (from left to right) in the Oxytricha mode. Based on both SSrRNA gene sequencing and morphogenetic data, the systematic positions of the genus Trachelostyla Borror, 1972 as well as the family Trachelostylidae Small and Lynn, 1985 are briefly analyzed. The results indicate that this genus/family could be a highly isolated lineage and might be ancestral to other well-known oxytrichids.     

Morphological,Ultrastructural, and Molecular Characterization of Euplotidium rosati n. sp. (Ciliophora,Euplotida) from Guam

We combined morphological (i.e. live, stained, scanning, and transmission electron microscopy) with morphometric and molecular analysis to describe a ciliate species collected from shallow reefs in Guam, grown, and maintained in our laboratory. The species was recognized as a member of Euplotidium, and compared with established species of the genus: Euplotidium itoi Ito 1958; Euplotidium psammophilus (Vacelet 1961) Borror 1972; Euplotidium arenarium Magagnini and Nobili 1964; Euplotidium helgae Hartwig 1980; Euplotidium prosaltans Tuffrau 1985, and Euplotidium smalli Lei, Choi and Xu, 2002. To obtain more elements to compare the species, new morphometric data and additional SSU rRNA gene sequences of E. itoi and of E. arenarium are reported. On the basis of this comparison, we established the new species Euplotidium rosati that has a cirral pattern composed of 12 frontoventral and six transverse cirri, and lacks the left marginal cirrus. Euplotidium rosati harbors on its dorsal surface epixenosomes, the peculiar extrusive symbionts described in other Euplotidium species. The whole body of our observations together with the analysis of the data available in the literature leads us to propose a redefinition of the genus. The results may also be useful to clarify the tangled relationship between Euplotidium and Gastrocirrhus.     

A parasitic scuticociliate infection in the Norway lobster (Nephrops norvegicus)

A histophagous ciliate infection was discovered in a number of Norway lobsters (Nephrops norvegicus) from the Clyde Sea Area, Scotland. Silver-carbonate staining of cultured ciliates revealed an oral apparatus and additional structural features that are morphologically similar to scuticociliates in the genus Mesanophrys, which are known to parasitize crustaceans. However, ribosomal DNA sequences (ITS1/5.8S/ITS2) of the ciliate were identical to Orchitophyra stellarum, a parasitic scuticociliate of sea stars with a different morphology from Mesanophrys spp. and to the ciliate from N. norvegicus. Associated pathology included degeneration and necrosis of the myocardial heart muscle, and large numbers of ciliates in the gill filaments.     

Species richness and ecological characterization of myxomycetes and myxomycete-like organisms in the canopy of a temperate deciduous forest

The ecological community of myxomycetes and myxomycete-like organisms (MMLO) in the canopy of living deciduous trees was studied in a riparian deciduous forest at Leipzig, Germany. A systematic survey carried out with a total of 146 moist chamber cultures resulted in 386 records of 37 taxa, with 32 myxomycetes, two myxobacteria, two protostelids and the fruit body forming ciliate Sorogena stoianovitchae, the latter recorded for the first time for Europe. With 94% of all cultures positive for MMLO, these organisms are present consistently in the investigated sections of white-rotten twigs attached to living trees at 10-30 m above the ground. Our sampling recovered a majority of the likely species, with 37 out of the 42-45 predicted according to a species-accumulation curve and two other estimators of species richness. Nonmetric multidimensional scaling revealed pH, water-holding capacity and stage of decay to explain most of the variation in species distribution. Arcyria cinerea and Perichaena depressa as the most common species occurred in 32% and 29% of all samples, respectively. Viewing the sampled twigs as habitat islands and a single spore as sufficient to establish a population, a simulation program assuming a random spore rain estimated an average of 0.4 and 0.35 spore hits per twig as necessary to explain the observed frequencies. This is matched by the potential productivity of the substrate. All fruit bodies from the cultured twigs would be able to create a spore rain of 86 (A. cinerea) or 40 (P. depressa) spore hits per twig when dispersed evenly over the plot. The terminal fall velocity of spores was measured, revealing that it took about 5 h for a spore to land (30 m) in still air and indicating high dispersal ability for canopy-inhabiting MMLO.     

Bromeliothrix metopoides,a boom and bust ciliate (Ciliophora,Colpodea) from tank bromeliads

We investigated the recently described colpodid ciliate Bromeliothrix metopoides in a series of laboratory experiments to reveal the environmental factors that constrain this species to its peculiar habitat, i.e. the tanks of bromeliads. Our results demonstrated that the various life stages of this ciliate (bacterivorous theronts and microstome trophonts, flagellate-feeding macrostomes) have specific demands in terms of food quality and quantity. Bromeliothrix required a high food threshold (>1.4 mg C L^?1) in order to thrive. Food quality also affected resting cyst formation of B. metopoides when the experimental containers dried out. Its maximum growth rates (μ_max = 4.71 d^?1, i.e. 6.8 doublings d^?1) belong to the highest ones recorded thus far for free-living ciliates. The pH niche of B. metopoides was relatively wide (pH ～4 to >9) under optimal food conditions. However, its high sensitivity to unfavourable environmental conditions let the population collapse within several hours. We conclude that B. metopoides is a boom and bust ciliate that is specifically adapted to its peculiar habitat but virtually unviable in other environments.     

Intestinal ciliate composition found in the feces of the Cypriot wild donkey,Equus asinus Linnaeus, 1758

Species composition and distribution of large intestinal ciliates was investigated in the feces from 13 Cypriot wild donkeys, free-living in the Karpaz national park, Northern Cyprus. We identified 16 ciliate genera and 22 species. This is the first report on intestinal ciliates in Cypriot wild donkeys, and no endemic species were observed. The genus Cycloposthium occurred in all animals. The mean number of ciliates was 3.0±2.5×10⁴ cells ml^?1 of feces and the mean number of ciliate species per host was 6.5±4.8. Characteristics of the wild donkey ciliates was almost identical to those reported in other equids from various regions around the world. We thus conclude that there is no pronounced geographic variation in the intestinal ciliate fauna of equids.     

Porpostoma guamensis n. sp., a philasterine scuticociliate associated with brown-band disease of corals

Brown band disease of coral is caused by a ciliate that consumes the tissue of the corals in the genus Acropora. We describe the ciliate associated with this disease on Guam, based on: general morphology, division stages, and ciliature observed on live and protargol-stained specimens; modification of the oral structures between divisional stages, observed on protargol-stained specimens; and some aspects of behavior in field and laboratory studies. Porpostoma guamensis n. sp. is elongate and has ciliature typical for the genus; live cells are 70-500 × 20-75 μm; the macronucleus is sausage-like, elongate but often bent, positioned centrally along the main cell axis; the oral ciliature follows a basic pattern, being composed of three adoral polykinetidal regions, as described for other species in the genus, although there is variability in the organization, especially in large cells where the three regions are not easily distinguished. Ciliates fed on coral with their oral region adjacent to the tissue, which they engulfed, leaving the coral a bare skeleton. Both zooxanthellae and nematocysts from coral occurred in the ciliates. Zooxanthellae appeared to be ingested alive but deteriorated within 2-3 days. Ciliates formed thin-walled division cysts on the coral and divided up to 3 times. Cysts formed around daughter cells within cysts. We provide some observations on the complex division pattern of the ciliate (i.e. tomont-trophont-cyst) and propose a possible complete pattern that requires further validation.     

记山东曲阜中始新世晚期─雷兽新属种

描述了产自山东曲阜黄庄动物群-雷兽新材料：周氏曲阜雷兽（新属、新种）Qufutitanzhouigen．etspnov。该材料是山东省内首次确定的需兽属种报道,它与Metatelmatherium属相似但较之进步,是已知后沼雷兽亚科（Metatelmatheriinae）在沙拉木仑期的唯一代表,与中国沙拉木仑期特有的鼻雷兽属（Rhinotitan）差别较大。     

“Candidatus Euplotechlamydia quinta,” a novel chlamydia-like bacterium hosted by the ciliate Euplotes octocarinatus (Ciliophora,Spirotrichea)

Our knowledge of ciliate endosymbiont diversity greatly expanded over the past decades due to the development of characterization methods for uncultivable bacteria. Chlamydia-like bacteria have been described as symbionts of free-living amoebae and other phylogenetically diverse eukaryotic hosts. In the present work, a systematic survey of the bacterial diversity associated with the ciliate Euplotes octocarinatus strain Zam5b-1 was performed, using metagenomic screening as well as classical full-cycle rRNA approach, and a novel chlamydial symbiont was characterized. The metagenomic screening revealed 16S rRNA gene sequences from Polynucleobacter necessarius, three previously reported accessory symbionts, and a novel chlamydia-like bacterium. Following the full-cycle rRNA approach, we obtained the full-length 16S rRNA gene sequence of this chlamydia-like bacterium and developed probes for diagnostic fluorescence in situ hybridizations. The phylogenetic analysis of the 16S rRNA gene sequences unambiguously places the new bacterium in the family Rhabdochlamydiaceae. This is the first report of chlamydia-like bacterium being found in Euplotes. Based on the obtained data, the bacterium is proposed as a new candidate genus and species: “Candidatus Euplotechlamydia quinta.”