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Much has been written on annual variation of tintinnid assemblages although the mechanism causing the annual variation has been poorly studied either in form of species richness or Lorica Oral Diameter (LOD) size-classes. In the present study, a 10-year (May 2003 to December 2012) survey on species occurrence, abundance, and LOD variation of the tintinnid ciliates was conducted in Jiaozhou Bay, western Pacific. In contrast to previous studies, we found summer peaks in tintinnid species richness in Jiaozhou Bay validated by multi-year investigations. We studied phenology of every tintinnid species and explored the mechanism causing the annual variation. The hypothesis was that tintinnid species richness has a winter baseline, to which warm water species added with the progress of the season. We defined the occurrence types of each species, and found there was only one cold occurrence type species. There was no overlap of cold occurrence type and warm occurrence type in the transitional period between winter and summer. The second aim of this study was to explore annual variations in tintinnid assemblages in form of LOD and redundant species. The species frequency distribution patterns among LOD size-classes were similar all year round. The abundance frequency distribution pattern in LOD size-classes could be divided into two phases: cold phase and warm phase with exception of May and September. The portion of redundant species was about 50% in every month. Our result help understand and predict annual variation of tintinnid assemblages in terms of species richness and LOD in world oceans.

Objective. Growth and mortality parameters of Cachana Cynopotamus atratoensis Eigenmann, 1907 in the cienaga Grande de Lorica, Sinu river basin, Colombia, were estimated. Materials and methods. The length frequency analysis to the information collected between January 2001 to December 2002, was applied. Results. The estimated values for asymptotic length, growth rate and age at zero length were 43.4 (±0.52) cm of total length, 0.29 (±0.02) year-1 and -0.53 years, respectively. Total mortality was estimated at 0.97 year-1, natural mortality at 0.72 year-1, fishing mortality at 0.25, the average catch size was 24.8 cm total length, being fully recruited to the fishery with 16.6 cm total length, with low exploitation rate (E: 0.26). Conclusions. Cachana is a fish with medium longevity and growth rate with low exploitation rate, suggesting that there is still no overfishing on the species. However, as it is an very important fish in the food security of fishermen and their families, its necessary to increase the basic biology research pointing to the management and conservation of the species in the cienaga and the Sinu basin.

Metacystis truncata, a prostomatid loricate ciliate, was found attached to Thalassia testudinum, a dominant seagrass of the coral reef lagoons of Veracruz, Mexico. The morphology of the ciliate and its lorica were studied in living and stained specimens and in those prepared for scanning electron microscopy. The lorica is cylindrical (64.6-115 μm) with a well-developed anterior neck and a sac reinforced by 15-26 rings. Cell body size is variable (19-91 μm live), from ovoid to elongate: the terminal protruding vacuole is conspicuous in small and medium-sized individuals; the macronucleus is terminal in the elongate forms, or located near the mid-body in the ovoid ones. This marine prostomatid colonizes both natural and artificial substrates such as narrow polyethylene strips placed in an aquarium. The highest density was found in the summer. The present study represents the first description of the lorica of M. truncata and the first record on T. testudinum shoots.

In water samples collected from the middle of Admiralty Bay (King George Island 62°08'S 58°25'W) between February 1990 and January 1991, 17 Tintinnina species were noted. Total Tintinnina numbers in summer were very high (up to 5000 cells m~'), but species diversity was low, consisting mainly of Cymatocylis affmislconvallaria, forma convallaria. During austral winter, cell numbers were very low, but species composition was diverse. Cymatocylis affmislconvallaria, forma affinis, and C.affmislconvallaria, forma convallaria, the polymorphic forms of one species C.affinisl convallaria, appear to be interchangeable during the year. The transition from one form to the other occurs in the spring and autumn. The typical Tintinnina polymorphism can be attributed to the prevailing environmental conditions.

En capturas realizadas por los pescadores de la zona se registra por primera vez para el bocachico, la presencia del protozoo parasit Myxobolus sp. afectando los peces en áreas adyacentes al caño aguas prietas de la Ciénaga Grande de Lorica.

To estimate biomass and production, the cell volume of tintinnine ciliates has been assumed to be 50% of lorica volume. This assumption was tested using a high-precision digitizing system which measured individuals of 17 tintinnine species in samples taken in two annual studies of biomass and production in both tropical (Kingston, Jamaica in 1986) and temperate (Passamaquoddy Bay, Canada in 1983–1984) regions. Using this assumption, percent occupancies and hence, biovolume estimates, were overestimated by as much as 317% for tropical species and 178% for temperate species. Daily production estimates of the tropical tintinnine assemblage were overestimated by as much as 147%. In studies attempting to estimate biomass and production accurately, it is concluded that cell volume of tintinnines should be measured directly rather than assumed to be 50% of lorica volume.

A total of 121 photographs was made of specimens in the tintinnid genus Ptychocylis, col- lected in the vicinity of TromsO, northern Norway. Selections are shown from these photographs to il- lustrate variations that occurred. In addition, detailed measurements were undertaken of 165 specimens from the same samples. From all of these and from the literature it is concluded that it is not feasible on the basis of lorica shape to distinguish among the following described species: P. acuta, P. arclica, P. basicurvaia, P. cylindrica. P. drygalskii, P. glatialis and P. obtusa. Further- more, some of the illustrated forms do not correspond to any descriptions found in the literature. It is concluded either that there is one multivariate species encompassing the above list, by priority to be named P. obtusa, or else that other means than the lorica alone must be used to distinguish species in this genus.

Qualitative structural details, amplifying or correcting previous accounts in the literature on this species have been compiled by means of light and/or electron microscopy of dry whole mounts, prepared in situ from freshly gathered wild material mainly from temperate sources in Denmark, Britain and South Alaska. The more important findings are summarized diagrammatically. These include elaborate and constant details of assembly at the anterior end of the lorica, combined with much greater variability at the hind end. The absence of continuity between the three anterior spines and any of the six longitudinal costae present at the front end of the lorica chamber is confirmed, but a range of conditions involving numerical reduction in costal numbers at the hind end is illustrated. The overall size range encountered in the three temperate localities listed is illustrated photographically, but the large cells characteristic of arctic sources are represented, for a qualitative purpose only, by means of a single photograph recording a specimen collected beneath sea ice in N. Alaska, a source which will be considered more fully on a later occasion.

Lorica volume, carbon, nitrogen, and ATP content were measured in nine species of tintinnid ciliates spanning a size range of two orders of magnitude. Tintinnid carbon was linearly related to both lorica volume and ATP content. The mean C:ATP ratio was 65. Tintinnid ATP as a percentage of total ATP in the < 153 /un fraction averaged 7% over an annual cycle in Narragansett Bay. It is concluded that ATP is a useful indicator of living phytoplankton carbon in pre-screened, smallvolume samples during periods of moderate to high phytoplankton biomass, but that protozoan microzooplankton interference is significant when phytoplankton standing stocks are low.

Evidence for the presence of silica in the costae of Stephanoeca diplocostata Ellis has been provided by a combination of light and electron microscopy. The solubility of costae in hydrofluoric acid has been demonstrated. The presence of silicon in the costae has been strongly confirmed by means of the X-ray analytical electron microscope (EMMA) but tests for a crystalline substructure by means of electron diffraction were negative; it is concluded that silicon is present in a crystallographically amorphous form. Preliminary observations on other biological aspects of the organism include the presence of a sac-like membrane between the lorica and protoplast, the presence of immature costal strips within the cytoplasm and the nature of ingested food. The phyletic position of the group is briefly discussed with special reference to mitochondrial substructure.

Photographs were made of the loricae of 272 specimens of the tintinnid genus Parafavella, encountered in plankton samples taken in the vicinity of Tromsø, northern Norway. From the loricae alone it is impossible to distinguish among P. cylindrica, P. gigantea, P. denticulata, P. dilitata, P. obtusangula, P. parumdentata, and P. elegans. The results are compared with those of other authors working with this difficult genus. It is emphasized that additional methods for the distinction of species must be undertaken beyond simple examination of the loricae if the taxonomic obscurities of the genus are to be unravelled.

SYNOPSIS. Tintinnida of the New York Bight (a bend in the coastline) were identified during the 1-year period August 1973–August 1974. Recurring genera included Stenosemella and Tintinnopsis; seasonal genera were mainly the hyaline Favella, Metacylis, and Helicostomella; exotic or unusual genera included Parafavella and Ptychocylis. Large size differences in loricae were found seasonally, related apparently, to water temperature.

Background Globally, amphibian species have suffered drastic population declines over the past 40 years. Hundreds of species are now listed as Critically Endangered, with many of these considered “possibly extinct”. Most of these species are stream-dwelling frogs inhabiting remote, montane areas, where remnant populations are hard to find using traditional surveys. Environmental DNA (eDNA) could revolutionize surveys for ‘missing’ and endangered amphibian populations by screening water samples from downstream sections to assess presence in the upstream catchments. However, the utility of this survey technique is dependent on quantifying downstream detection probability and distances. Methods Here we tested downstream detection distances in two endangered stream frogs (Litoria lorica and L. nannotis) that co-occur in a remote stream catchment in north-east Australia, and for which we know precise downstream distributional limits from traditional surveys. Importantly, the two last populations of L. lorica persist in this catchment: one small (~1,000 frogs) and one very small (~100 frogs). We conducted eDNA screening at a series of sites kilometers downstream from the populations using precipitation from two fixed water volumes (15 and 100 mL) and via water filtering (mean 1,480 L). Results We detected L. nannotis and the small L. lorica population (~1,000 frogs) at most sampling sites, including 22.8 km downstream. The filtration method was highly effective for far-downstream detection, as was precipitation from 100 mL water samples, which also resulted in consistent detections at the far-downstream sites (including to 22.8 km). In contrast, we had limited downstream detection success for the very small L. lorica population (~100 frogs). Discussion The ecological aspects of our study system, coupled with thorough traditional surveys, enabled us to measure downstream eDNA detection distances with accuracy. We demonstrate that eDNA from a small population of approximately 1,000 frogs can be detected as far as 22.8 km downstream from the population. Water filtration is considered best for eDNA detection of rare aquatic species—indeed it was effective in this study—but we also achieved far-downstream detections when precipitating eDNA from 100 mL water samples. Collecting small water volumes for subsequent precipitation in the lab is more practical than filtration when surveying remote areas. Our downstream detection distances (>20 km) suggest eDNA is a valuable tool for detecting rare stream amphibians. We provide recommendations on optimal survey methods.

Dinoflagellates can serve as predators or parasites of tintinnid ciliates. Known predators feed on the ciliate from outside the tintinnid lorica, while parasites either grow in the host cytoplasm or feed inside in the lorica while attached to the outside of the host cell. Here we report mixotrophic species of Scrippsiella that enter the lorica to consume the ciliate zooid of Helicostomella subulata from Denmark and multiple tintinnid species from Korea. We contrast morphology and life-history stages of these mixotrophic predators with dinokaryote parasites of tintinnids and address phylogenetic relationships based on rDNA sequences. Mixotrophic Scrippsiella species sometimes attack tintinnids that are simultaneously infected by syndinean dinoflagellates, complicating study of life histories and potentially leading to confusion about trophic status and taxonomy.

Cell coverings can be observed in all major groups of organisms, which include animals, plants, fungi, protists and prokaryotes. They play a key role in assuring cell survival or adaptation to certain environmental conditions. Since the term algae refers to a polyphyletic and very artificial group, the cell coverings of these organisms are very diverse in molecular composition and with different arrangements. Differences have taxonomic value since they allow microalgae phyla or even minor taxonomic groups, such as classes, orders or families, to be distinguished. Understanding the structure of cell coverings is also fundamental for the use of microalgae to obtain products of commercial value. Despite its importance, the composition and architecture of microalgae coverings is still poorly understood, especially considering the great diversity of organisms. Diatom frustules are the most studied coverings due their uses in areas of bio- and nanotechnology. There is a lack of information about the cell wall, lorica, periplast, amphiesma and scales. This study is a review with the aim of synthesizing literature information on microalgae cell coverings to describe their compositions, arrangements, functions and industrial uses.

The unicellular flagellates of the genus Phacotus, which form a solid calcite lorica by extracellular precipitation of calcium carbonate are some of the nanoplankters quite frequently occurring in hardwater ecosystems of the temperate zone. The aim of this study was to describe seasonal changes of Phacotus lenticularis populations in several types of water bodies (a glacial lake, small and shallow ponds, and a lowland river) in relation to some environmental parameters. All the water bodies are subject to multiple human pressure: recreation, fishing, agriculture, and urbanization. P. lenticularis individuals preserved in Lugol’s solution were counted under an inverted microscope (after sedimentation in 14 or 9 ml chambers), including both empty and filled loricae. Its populations differed both between seasons and between waters. High P. lenticularis abundance was mainly limited to the summer months. It was observed at temperatures above 19°C and pH values above 7.8, in water characterized by quite high electrolytic conductivity (>500 μS cm-1). Statistical analysis reveals two significant relationships between physicochemical parameters and the abundance of P. lenticularis. This suggests that in the investigated waters the biotic factors and processes are probably more important regulators of changes in the density of its population than nutrients.

The suctorian ciliate Thecacineta calix is reported off the coast of Panama, Florida (USA) epibiont on meiobenthic harpacticoid copepod. This is the first report of T. calix from Florida coast. The length of stalk in the present specimens, epibiont on harpacticoids, ranged from one seventh to one eighth of the lorica length.

The article focused on morphological peculiarities, chemical composition and function of the loricae in ciliates. Pseudochitinous (tectinous), hyaline and mucopolysaccharide loricae differ by chemical composition. There are also composite (pseudochitinous + mucopolysaccharide) and agglutinated loricae. The morphological features and associated protective properties of loricae and semi-loricae of sessile ciliates are also discussed. The increase in floatability of cells has been reported in literature as the main function of mucopolysaccharide and hyaline loricae in planktonic ciliates. It is the authors’ opinion that the main function of the lorica is to prevent the contact of extrusomes or other capturing organelles of unicellular predators or parasites from the cellular membrane of ciliates. It is also assumed that another important function of the semi-loricae and loricae in sessile ciliates is to protect joints between their stalk and zooid from hydrodynamic loads.

There are only five studies on tintinnids of the Philippines. We present a checklist of tintinnids (Ciliophora, Oligotrichea) from Masinloc-Oyon Bay, Province of Zambales, West Philippine Sea. Masinloc-Oyon Bay is a unique in having both marine protected areas and a coal-fired thermal power plant within the same bay. Field sampling was performed in July 2017, which recorded 10 species belonging to one order, six families, and seven genera. Station 1 inside the power plant’s outfall had the lowest diversity, whereas the stations within marine protected areas had a relatively higher species diversity index. Our new data are the first records of tintinnid species in Masinloc-Oyon Bay. These records add to the regional checklist of the Philippine Sea.

Tintinnid ciliates are an important link in marine food webs as they feed on phytoplankton and bacteria while providing nutrients to higher trophic levels. Tintinnids are known to agglutinate mineral particles or dead biogenic material such as diatom frustules to their shell-like housing (lorica), however, reasons for this agglutination remain questioned. We report on our observation of agglomeration of the living diatoms Fragilariopsis curta, F. cylindrus, F. pseudonana and F. rhombica to loricae of the Antarctic tintinnid ciliates Laackmanniella naviculaefera and Codonellopsis gaussi. These unusual associations between living diatoms and tintinnids were exclusively observed south of 63.59°S. We discuss the significance of our new finding and generate hypotheses to be tested by future research. It remains unclear where these living diatom–tintinnid associations are initially formed (in or near sea ice or also further north when abundances of L. naviculaefera, C. gaussi, F. curta, F. cylindrus, F. pseudonana and F. rhombica happen to be relatively high); who the beneficiary is in this association; what the exact benefits are; and how they might influence the Southern Ocean carbon cycle. Nevertheless, our observation provides a key step forward towards illuminating the largely unknown ecology of two Southern Ocean-endemic tintinnid species.

Evidence is found of selectivity for certain materials used in lorica-building, and there appears to be selection for particles according to size as well. There are striking differences in the proportions of biogenic: non-biogenic materials on the loricae of various specimens, and this appears to have taxonomic significance. Certain species apparently produce the lorica in the sediments; the development of others appears to take place in the water column.

An annual community structure of the loricate ciliate tintinnids, the ubiquitous planktonic protist, was analysed from nine sampling sites ( n = 108 ) of diverse environmental stresses along the Hooghly (Ganges) River Estuary, eastern coastal part of India. The agglomerated genus Tintinnopsis sp., was dominated among the 32 identified tintinnid species (3 core, 12 seasonal and 17 occasional species) contributing ∼62% of total tintinnid population. The size-class distribution of lorica oral diameter ranges between 9 and 22 μm for majority of the tintinnids (∼71%) which provides relevant information on the ecological characteristics for the species assemblages. The maximum species diversity for tintinnid ( H ′ = 1.71 ) during postmonsoon (February, 2014) has been attributed by high numerical density of phytoplankton dominated by diatoms (4400 cells l − 1 , H ′ = 3.41 ) at the site Gangasagar, mouth of the estuary. The large-sized tintinnids Tintinnopsis cylindrica (lorica length = 262.8 μm; lorica oral diameter = 65 μm) and T. radix (lorica length = 278.6 μm; lorica oral diameter = 62 μm) belonging to family Codonellidae, formed successful dominant group (>50% of the total) in this estuarine ecosystem. The core species abundance ( Tintinnopsis beroidea, Tintinnidium primitivum and Leprotintinnus simplex ) shares ∼57% of total tintinnid population followed by seasonal (35%) and occasional species (8%), characterized by their eurythermal and euryhaline nature. As revealed from the results of cluster analyses, majority of the tintinnids formed an individual functional group, exhibiting similar assemblages in species distribution. The Canonical Correspondence Analysis map (CCA) revealed a clustering of core species with the phytopigment (Chlorophyll a ) and dissolved oxygen which were found to be the most important causative factors controlling the distribution and seasonal patterns of tintinnids. Well-defined tintinnid assemblages are evident representing the fingerprint of the specific ecological zone of Hooghly estuary, characterized by a set of environmental variables.

This study investigated the effects of chicken manure extract (CME) on the population growth, mixis induction and body size of the freshwater rotifer Brachionus angularis Gosse 1851. Four concentrations of CME (i.e.0.5, 1.0, 2.0 and 3.0 ml.L-1), each in triplicate, were used in glass jars containing 20 mL of sterilised pond water. Thirty clones (24 h old) of B. angularis were placed in each jar and the specified concentrations of CME were added except in the control jars. Chlorella vulgaris Beijerinck 1890 (2.5x106 cells.mL-1) was supplied daily in all jars. The treatments were incubated at 25 oC in darkness for 7 days without exchanging water. CME significantly (P.L-1 but reduced the mixis induction rate. However, the CME did not significantly (P>0.05) affect the unfertilised mictic females. The specific population growth rate was significantly (P.L-1 of CME. The resting egg production decreased with increasing concentrations of CME. The lorica length increased at 3.0 mL.L-1 of CME but the lorica width was unaffected by CME. These results suggest that addition of 2.0 mL.L-1 of CME enhances the population growth and regulates lorica size; hence can be applied in the freshwater larviculture initiatives., Asian Fisheries Science, 28(4), pp.174-185; 2015

The bocachico (Prochilodus magdalenae) it is the main species of the fishery the basins of the magdalena and sinú rivers, due to their great acceptance and commercial value in Colombia. Between April and June of 2000, 44 specimens were gathered between Lorica and Tierralta, with sizes between 19.4 and 28.2 cm. of standard longitude (SL) and 24.6 and 35.0 cm. gives overall length (OL), with all up weights between 212.0 and 600.0 g. The were placed in Gilson solution, being applied the gravimetric method for the estimate and the fecundity. The size and weight average were 23.9 cm (± 2.0), 369.0 g (±80.0), respectively. The weight of the ovaries oscillated between 38.9 and 168.8 g, averaging 87.6 g (± 29.6), with high fecundity and fluctuating between 69981 and 357012 eggs with average of 153114 (± 57491). The beginning sizes (BS) and half maturity (HM) were 19.4 and 23.8 cm. Of OL, with significant differences (p=0.01) to those reported by Valderrama & Vejarano (2001). The results of this study they allow to establish preliminarily that they are capturing fish whose size mediates of capture (SMC = 23.2 cm. OL) estimated by Valderrama & Vejarano (2001) it is smaller than the SMC. Comparing the SMC with the HM recommended by the INPA (Instituto Nacional de pesca y acuicultura) for the fishery of the river Sinú it was observed that the difference is bigger, what suggests the regulation gives the fishery as soon as possible. The Estimated equations were: Wt = 0.16 LS 1.78, r = 0.92; F = 518.89 OL 1.78, r = 0.43; F = 427.23 Wt 0.99, r = 0.63 and F = 30182.27 Wg 0.35, r = 0.34. The regression all up weight - fecundity the one that presented better correlation with regard to the other two relationships was that they involve to the number of estimated eggs, which confirms that the fecundity is closely related with the weight of the fish; while the coefficient of growth (b) of the relationship longitude - I weigh it is negative alometric, although all the correlation coefficients are significant to 95%. The estimates of this study allowed Yepes to reassess (1998), who reported 35000 ovocells of average for the induced reproduction of the bocachico (Prochilodus magdalence) in the river Sinú with sizes between 23.0 and 25.0 cm. (LS) and 148940 for the bocachico in the Atrato river., El Bocachico (Prochilodus magdalenae) es la principal especie de la pesquería en las cuencas de los ríos Magdalena y Sinú, debido a su gran aceptación y valor comercial en Colombia. Entre abril y junio de 2000, se recolectaron 44 ejemplares entre Lorica y Tierralta, con tallas entre 19.4 y 28.2 cm de longitud estándar (LS) y 24.6 y 35.0 cm de longitud total (LT), pesos totales entre 212.0 y 600.0 g. Las gónadas se colocaron en solución Gilson, aplicándose el Método gravimétrico para la estimación de la fecundidad. La talla y peso promedios fueron 23.9 cm (± 2.0), 369.0 g (± 80.0), respectivamente. El peso de los ovarios osciló entre 38.9 y 168.8 g, promediando 87.6 g (± 29.6), con fecundidad alta y fluctuando entre 69981 y 357012 huevos con promedio de 153114 (± 57491). Las tallas de inicio (TIM) y media de madurez TMM) estimadas fueron 19.4 y 23.8 cm de LS, con diferencias significativas (p

To cope with predation, many prey species have developed inducible defenses in terms of morphology, behavior, and life history. Rotifers were the first model organisms used to evaluate the ecology and evolution of inducible defenses in aquatic ecosystems. Since the middle of last century, only visible morphological defenses, such as spine development, have been found and only in a few rotifer species. Given the development of ultrastructural defenses is taxonomically widespread in aquatic ecosystems, we hypothesize that rotifer prey, particularly small-sized species, can develop such inducible defenses. We evaluated morphological response of two common Brachionus herbivores (B. calyciflorus and B. angularis) to predatory rotifer Asplanchna brightwellii. Results confirmed existence of predator-induced ultrastructural defenses, which are expressed as increased lorica thickness and enhanced lorica hardness. Such inducible defenses are more evident and effective in the smaller sized B. angularis, leading to higher fitness of B. angularis in predator-prey interactions. As anticipated, development of defenses has inevitable fitness costs manifested as decreased reproduction or reduced sex investment. Our results not only extend understanding of inducible ultrastructural defense to other planktonic taxa that were previously observed only in cladocerans, but also verify effective mechanical protection of such hidden defensive morphology.

During a pluri-disciplinary study carried out within the frame of the Spanish research project DOS MARES, multicore samples were collected along the Blanes submarine canyon and its adjacent open slope to study the structure and dynamics of the meiofaunal organisms, mainly nematodes. Among the 5808 nematode individuals identified, only 190 of them belonged to the genus Tricoma (Desmoscolecidae), and only two harboured epibiont suctorian ciliates. The three specimens were located near the tail of the basibionts. A careful examination of the ciliates revealed that they were suctorians, which are here described as a new species of Loricophrya, namely L. mediterranea sp. nov. The new species is characterized by having a conical, slightly elongated lorica, narrowing towards posterior end; an anterior end inward curved, surrounding the lorica opening; a body placed near the lorica opening, occupying 1/3 of the lorica length, 4–8 capitate tentacles, and a peripheral, oval to sausage-shaped macronucleus. Our findings represent the first known report of an association with a deep-sea species of Tricoma, and the first record in the Mediterranean Sea, for a species of Loricophrya. The significance of the relationships between suctorian ciliates and their host in extreme environments such as deep-sea submarine canyons is discussed.

International audience; Pneumocystis fungi are opportunistic parasites of mammalian lungs whose evolution, ecology and host specificity in natural host populations remain poorly understood and controversial. Using an extensive collection of 731 lung samples from 27 rodent species sampled in five Southeast Asian countries, and nested PCR amplification of mitochondrial and nuclear genes, we investigated the host specificity and genetic structure of Pneumocystis lineages infecting wild rodents. We also identified the rodent species playing a central role in the transmission of these parasites using network analysis and centrality measurement and we characterized the environmental conditions allowing Pneumocystis infection in Southeast Asia using generalized linear mixed models. Building upon an unprecedented Pneumocystis sampling from numerous rodent species belonging to closely related genera, our findings provide compelling evidence that the host specificity of Pneumocystis lineages infecting rodents is not restricted to a single host species or genus as often presented in the literature but it encompasses much higher taxonomic levels and more distantly related rodent host species. The phylogenetic species status at both mitochondrial and nuclear genetic markers of at least three new Pneumocystis lineages, highly divergent from Pneumocystis species currently described, is also suggested by our data. Our models show that the probability of Pneumocystis infection in rodent hosts is positively correlated to environmental variables reflecting habitat fragmentation and landscape patchiness. Synanthropic and habitat-generalist rodents belonging to the Rattus, Sundamys and Bandicota genera played a role of bridge host species for Pneumocystis spreading in these heterogeneous habitats, where they can reach high population densities. These are critical findings improving our understanding of the ecology of these enigmatic parasites and the role played by cospeciation and host switches in their evolution. Our results also confirmed the role of land-use change and habitat fragmentation in parasite amplification and spillover in rodents.

Marine planktonic ciliates are important components of microzooplankton. Depending on the presence or absence of lorica, planktonic ciliates can be divided into tintinnids and aloricate ciliates. We hypothesize that the ecological distributions of the two groups were different due to their difference in morphology. To test this hypothesis, the spatial distribution of ciliates was studied in spring, summer and autumn 2011 in the East China Sea, a large marginal sea significantly affected by freshwater discharge. We found that tintinnids and aloricate ciliates had different vertical distributions. Tintinnids were distributed mainly near the bottom waters, while higher abundance of aloricate ciliate was found in waters 30-70 m above the bottom. The contribution of tintinnids to the total ciliate abundance decreased with increasing distance from the bottom. In waters with distance from the bottom >80 m, tintinnids accounted for

The species richness and abundance of tintinnids in the surface waters at 23 stations located in southeast of Hawaii were investigated between 14 August and 18 September 2013. A total of 36 species in 22 genera were identified. All tintinnid species had hyaline loricae. The species richness of tintinnids in each station ranged from 15 to 21. Tintinnid abundance and biomass ranged from 4,730 to 23,693 ind./m, and from 9.60 to 88.61 μg C/m, respectively. The top four dominant species were Ascampbelliella armilla, Steenstrupiella steenstrupii, Eutintinnus tenuis and S. gracilis. These top four dominant species were in different lorica oral diameter (LOD) size-classes.

In many small planktonic rotifers, predator kairomones induce the development of longer spines, which can provide effective post-contact defense against the predators. This review briefly discusses potential trade-offs associated with pronounced spine development, focuses on an evaluation and synthesis of experimental work comparing the reproductive potential of basic (non-induced) and Asplanchnainduced morphs and suggests areas for future research. To date, the only convincing evidence for an association between induced spine development and reduced reproduction is for Keratella testudo. This rotifer has a dense lorica (skeleton), so that elongated spines increase its sinking rate and thus presumably an offsetting swimming effort. In contrast, several studies with Brachionus calyciflorus and Keratella tropica, which have a thin lorica, showed that morphs with pronounced spine development reproduced at the same rate as basic morphs. In other studies with several different species, and also with B. calyciflorus, the presence of Asplanchna did inhibit reproduction. However, this inhibition generally was not clearly related to Asplanchna density or the degree of spine development, and could not be attributed to a defense cost. While predator-induced morphs of some species do not have a

International audience; The latitudinal diversity gradient is a well-known biogeographic pattern. However, rarely considered is how a cline in species richness may be reflected in the characteristics of species assemblages. Fewer species may equal fewer distinct ecological types, or declines in redundancy (species functionally similar to one another) or fewer trace species, those occurring in very low concentrations. We focused on tintinnid ciliates of the microzooplankton in which the ciliate cell is housed inside a species-specific lorica or shell. The size of lorica oral aperture, the lorica oral diameter (LOD), is correlated with a preferred prey size and maximum growth rate. Consequently, species of a distinct LOD are distinct in key ecologic characteristics, whereas those of a similar LOD are functionally similar or redundant species. We sampled from East Sea/Sea of Japan to the High Arctic Sea. We determined abundance distributions of biological species and also ecological types by grouping species in LOD size-classes, sets of ecologically similar species. In lower latitudes there are more trace species, more size-classes and the dominant species are accompanied by many apparently ecologically similar species, presumably able to replace the dominant species, at least with regard to the size of prey exploited. Such redundancy appears to decline markedly with latitude in assemblages of tintinnid ciliates. Furthermore, the relatively small species pools of the northern high latitude assemblages suggest a low capacity to adapt to changing conditions.

A new acanthoecid choanoflagellate species, Acanthocorbis mongolica sp. nov. was found in preserved phytoplankton samples from the freshwater lake Bayan Nuur (Uvs Nuur Basin, NW Mongolia) in concentrations of up to 1.8 × 10 5 cells L −1 . It is the first well-documented species of the mainly marine order Acanthoecida to be found in a freshwater lake. The lorica structures were studied with scanning electron microscopy. Key morphological features of the vase-shaped lorica are spine bases that are composed of multiple (2–4) parallel costal strips, and the existence of two transverse costae. The ecological implications of this find are discussed.

Synchroma grande (Synchromophyceae, Heterokontophyta) is a marine amoeboid alga, which was isolated from a benthic habitat. This species has sessile cell stages (amoeboid cells with lorica and cysts) and non-sessile cell stages (migrating and floating amoebae) during its life cycle. The different cell types and their transitions within the life cycle are described, as are their putative functions. Cell proliferation was observed only in cells attached to the substrate but not in free-floating or migrating cells. We also characterised the phagotrophy of the meroplasmodium in comparison to other amoeboid algae and the formation of the lorica. The functional adaptations of S. grande during its life cycle were compared to the cell stages of other amoeboid algae of the red and green chloroplast lineages. S. grande was found to be highly adapted to the benthic habitat. One sexual and two asexual reproductive strategies (haplo-diploid life cycle) support the ability of this species to achieve rapid diversification and high adaptivity in its natural habitat.

This study selected small (100–120 μm) egg-bearing females from a local Thai ss population and characterized their first offspring‘s life history in an attempt to produce small-size rotifers. Mean lorica length of selected small adult females was 120 ± 6 μm at the time of collection, and this mean length did not increase over their lifetime. While their first offspring life span was only 5.11 ± 0.35 d, the reference population longevity was higher, 9.65 ± 0.4 d. The length of reproductive period of offspring from the small-size egg-bearing female was 2.58 ± 0.38 d, shorter than that of reference population 6.83 ± 0.58 d. Although the rate of egg production was not different between small egg-bearing female and reference population, the total number of eggs produced by the small egg-bearing female’s first offspring was lower (4.78 ± 0.60) compared to the reference population (11.83 ± 1.26). The small egg-bearing female’s first offspring had a higher egg to lorica length ratio (76.1 ± 1.64%) than the reference population (56.6 ± 1.3%), indicating a relatively high investment in reproduction. The small egg-bearing female’s first offspring reached only 125 ± 6 μm in 36 h, and further culture of their offspring over 35 d resulted in a mean offspring size, 163 ± 11 μm, similar to the reference population (159 ± 16 μm). This shows that population mean size reduction is not likely to result from selecting small egg-bearing females within a single generation. The unique reproductive characteristics of small egg-bearing female place it in its own category.

Trachemys callirostris is a turtle species endemic to northern South America. In northern Colombia it occurs in the middle and lower Magdalena River drainage and its principal tributaries (lower Cauca and San Jorge rivers) and in other minor drainages such as the lower Sinu River. In recent years, industrial, agricultural, and mining activities have altered natural habitats in Colombia where this species occurs, and many of the pollutants released there are known to induce genetic alterations in wildlife species. The micronucleus test and comet assay are two of the most widely used methods to characterize DNA damage induced by physical and chemical agents in wildlife species, but have not been employed previously for genotoxic evaluations in T. callirostris. The goal of this study was to optimize these genotoxic biomarkers for T. callirostris erythrocytes in order to establish levels of DNA damage in this species and thereby evaluate its potential as a sentinel species for monitoring genotoxic effects in freshwater environments in northern Colombia. Both genotoxic techniques were applied on peripheral blood erythrocytes from 20 captive-reared T. callirostris individuals as a negative control, as well as from samples obtained from 49 individuals collected in Magangue (Magdalena River drainage) and 24 individuals collected in Lorica (Sinu River drainage) in northern Colombia. Negative control individuals exhibited a baseline frequency of micronuclei of 0.78±0.58 and baseline values for comet tail length and tail moment of 3.34±0.24µm and 10.70±5.5, respectively. In contrast, samples from both field sites exhibited significantly greater evidence of genotoxic effects for both tests. The mean MN frequencies in the samples from Magangue and Lorica were 8.04±7.08 and 12.19±12.94, respectively. The mean tail length for samples from Magangue and Lorica were 5.78±3.18 and 15.46±7.39, respectively. Finally, the mean tail moment for samples from Magangue and Lorica were 23.59±18.22 and 297.94±242.18, respectively. The frequency of micronuclei in the samples was positively related to comet tail length and tail moment. Thus, this study showed that both genotoxicity biomarkers may be applied to T. callirostris erythrocytes as a sentinel organism for assessing the effects of environmental pollutants in freshwater ecosystems in northern South America.

Enriched commercial and artificial diets are unsuitable for the post larval stages of various commercially important crustacea and fish, which require live foods (such as rotifers, brine shrimp or fairy shrimp). The larger size of the brine shrimp and fairy shrimp make them unsuitable for larval fish and shrimp requiring small zooplanktons such as rotifers, as their initial diet. This study was designed to develop a reliable technique for inducing population growth, mictic female production and body size in the freshwater rotifer, Brachionus calyciflorus by treatment with the synthetic hormone Ovaprim. Ovaprim is a synthetic GnRH analogue with domperidone. Concentrations of Ovaprim from 0.05, 0.5, 5 and 50 μl ml − 1 were added to Chlorella vulgaris suspension (2 × 10 6 cells ml − 1 ). Population growth significantly increased in treatments exposed to 0.05 and 0.5 μl ml − 1 while higher mortality was observed at the concentrations of 50 and 5 μl ml − 1 . Ovaprim had no effect on mictic female production and hence also on the resting egg production. Lorica length increased to 19.47 and 19.16 μm in rotifers treated with 0.5 and 0.05 μl ml − 1 hormone concentrations and decrease in lorica length was observed at 50 and 5 μl ml − 1 concentrations (13.44 and 15.17 μm). Increase in the lorica width (13.41 μm) was observed on treatment with 0.5 μl ml − 1 concentration of Ovaprim when compared to the control. The results of the experiment suggest that Ovaprim treatment at 0.5 μl ml − 1 concentration have significant modulatory effects on the population growth, mictic female production and body size of B. calyciflorus.

Colacium minimumFott & 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 ofTrachelomonasEhrenb. andStrombomonasDeflandre taxa byC. minimumin natural populations is briefly discussed and originally documented using LM and SEM.

Morphological variations of euryhaline rotifers Brachionus, including lorica size and form, have been recognized since they have been used as the live food for finfish larvae. Based on these morphological variations, rotifer populations were divided into different morphotypes. Finfish larvae ingest suitable size of feed fitting to their mouth size. Therefore, the size of rotifer fed to larval fishes should also be optimum for the larval mouth. Newly aquacultured fish species increased dramatically; thus, rotifers with optimum size for these species are required. In order to obtain such rotifers, the search for a new type or population and artificial manipulation to change the size has been attempted. Consequently, the newly found and developed rotifer species for aquaculture were applied to the larval rearing of fish species with small mouth. Up to date, cross-mating is the only method to develop new rotifer strains. Therefore, strict management is necessary to avoid the contamination among different rotifer species and strains.

Specimens of the marine tanaid crustacea Halmyrapseudes spaansi , sampled in temporary littoral muddy patches near the mouth of the Kaw river (French Guiana, SE America), showed protozoan epibionts herein described as a new species: Cothurnia guyanensis sp. n. (Ciliophora, Peritrichia). These ciliates were covered by a cylindrical or bell-shaped lorica containing an oval elongated zooid with a rounded contractile vacuole located anteriorly in lateral position. The macronucleus was “S” shaped. The peristomial disk was anterior and included a polikinety and a haplokinety. The external stalk was short and broad, with 8–18 longitudinal conspicuous striations. Between the external stalk and the zooid, there were an endostyle and an mesostyle both short and broad. The striations of the external stalk were prolonged in the mesostyle. Telotroch stages were observed and described, as well as specimens with two zooids per lorica. Epibionts located on the ventral area, pereopods and antennae of the basibiont.

This study investigates two different effects of an ostracod on a rotifer. The rotifer Keratella tropica and the ostracod Cypris pubera were cultured on the alga Cryptomonas erosa. Adult ostracods (2.2 mm body length) significantly reduced the population growth rate (r day–1) of K. tropica from 0.42 to 0.13. Individuals of this size ingested live rotifers and produced fecal pellets with rotifer loricas. Smaller ostracods (both 0.59 and 1.61 mm body lengths) did not affect K. tropica 's population growth rate. Surprisingly, C. pubera significantly inhibited spine development in K. tropica. Rotifers cultured with juvenile, non-predatory ostracods had similar lorica lengths but right and left posterior spines that were 10 and 30% shorter, respectively. The spine reduction induced by the ostracod kairomone is in striking contrast to the spine elongation induced in this rotifer by kairomones from copepods, cladocerans and Asplanchna. In shallow ecosystems, large ostracods that swim in the plankton may be important predators of rotifers. In addition, the presence of ostracods in plankton communities may be one of many factors affecting rotifer spine development. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A new and a unique Brachionus rotifer was found in Hwajinpo coastal lagoon in Gangwon Province, South Korea. This Brachionus certainly originated from the wild rather than from aquaculture stations because Hwajinpo coastal lagoon has been under rigorous control as a military protected area and therefore could not have been contaminated by aquaculture stations. The new strain was identified as Brachionus rotundiformis based upon its morphological characteristics. The parthenogenetic female of this new rotifer strain typically shows characters similar to those of B. rotundiformis, such as the pot shape of the body, rounded dorsal plate compared with flattened ventral plate, elliptical mictic egg, four frontal spines, six pointed occipital spines, non-nodal foot, two toes, trophi typical of the Brachionus genus with five uncus plates resembling comb teeth, one wide symmetrical manubrium and ramus, and no stiffened spine as is seen in freshwater Brachionus rotifers. Moreover, its lorica was rather small in size compared with other common rotifer strains that serve as live-food organisms (Guam, Thai, and Bali strains). This new and unique Korean brackish rotifer, a B. rotundiformis strain, was therefore named the National Fisheries Research and Development Institute (NFRDI) N° 1 rotifer strain.

The morphology and distribution of the diatoms Chaetoceros tetrastichon and Ch. dadayi as epiphytes on the loricae of the tintinnids Eutintinnus apertus and E. pinguis investigated in the open waters of the Pacific Ocean. The Eutintinnus–Chaetoceros consortia was encountered in 38 of the 52 sampling stations from 34°N to 33°S, and together were among represented the most wide-spread species. The abundance was low with a maximum of 32 consortia l−1 and E. apertus was often the most abundant species of the genus. The free-living Eutintinnus congeneric species showed a wider vertical distribution, whereas E. apertus–Chaetoceros tended to be near the surface. The success of E. apertus in consortium with Chaetoceros may be due to increase of the clearance rate and/or the lower susceptibility to predation. Chaetoceros modifies its morphology to adapt the epiphytic life, especially Ch. dadayi. The shorter curved setae may facilitate the transfer to the lorica of the daughter tintinnid after the cell division. The free-living Ch. tetrastichon and Ch. dadayi are very rare and Chaetoceros remained attached to empty loricae or encysted tintinnid cells. This suggests that the Eutintinnus–Chaetoceros consortium is obligate for the success of the diatom and renders the tintinnid more competitive versus congeneric species.

Herein, we redescribe a tintinnid ciliate that is most commonly known as Tintinnopsis corniger Hada, 1964; but it has been described several times with different names, specifically Tintinnopsis nudicauda Paulmier, 1997 and Rhizodomus tagatzi Strelkow & Wirketis, 1950. Neotype material was collected from the water column of the coastal saline Lake Faro, a meromictic basin connected to the Straits of Messina, Central Mediterranean. The Lake Faro population is characterized by a hyaline or sparsely agglomerated lorica, which made it possible to observe in detail the basal layer structure, usually concealed by abundant incrusting particles. Along with an improved description of the lorica, we provide novel information, such as the general zooid morphology, the ciliary pattern, and the small subunit rRNA (SSU rRNA) gene sequence. Our phylogenetic analysis, based on the SSU rRNA, groups this species with Tintinnopsis radix, while the first taxonomic study designated it as R. tagatzi, introducing a new genus due to peculiarities in lorica morphology. We conclude that the species should be known as R. tagatzi, the senior synonym for the species. However, we do not transfer any other species to this genus, despite strong molecular similarities. Although it is obvious that the genus Tintinnopsis is in need of a thorough revision, current molecular and cytological information for this genus is too sparse, and the type species has not yet been redescribed with modern methods.

Ehrenberg (1838) defined the genus Trachelomonas as flagellated animals with shells. Posterior descriptions embraced morphological and cytological aspects as well as reproduction. The purpose of this work is to make a review on the structure of the envelope of the genus Trachelomonas. A compilation on the characteristics of the genus, lorica formation, structure, elementary composition and ecology is presented.