Loricate choanoflagellates (Acanthoecida) from warm water seas. VI. Pleurasiga Schiller and Parvicorbicula Deflandre

The loricate choanoflagellate genera Pleurasiga and Parvicorbicula are taxonomically ambiguous. Pleurasiga because of the uncertainty that relates to the true identity of the type species, and Parvicorbicula because too many newly described species over time have been dumped here in lack of better options. While all species currently allocated to the genus Pleurasiga (with the exception of the type species) are observed in our samples from the global warm water belt, the genus Parvicorbicula is represented by just a few and mostly infrequently recorded taxa. Two new species, viz. Pl. quadrangiella sp. nov. and Pl. minutissima sp. nov., are described here. While the former is closely related to Pl. echinocostata, the latter is reminiscent of Pl. minima. Core species of Pleurasiga and Parvicorbicula deviate from the vast majority of loricate choanoflagellates in having both the anterior and the mid-lorica transverse costae located exterior to the longitudinal costae. In Pl. quadrangiella there is no mid-lorica transverse costa but rather a small posterior transverse costa located inside the longitudinal costae. In Pl. minutissima the mid-lorica transverse costa has extensive costal strip overlaps which reveal patterns of costal strip junctions that deviate from the norm.     

Loricate choanoflagellates (Acanthoecida) from warm water seas. VII. Calotheca Thomsen and Moestrup,Stephanacantha Thomsen and Syndetophyllum Thomsen and Moestrup

The tectiform loricate choanoflagellate genera Calotheca, Stephanacantha and Syndetophyllum have all been first described from warm water habitats and share the presence of flattened and often elaborate costal strips in the lorica. The current reinvestigation does confirm both the widespread occurrence of these taxa within the global warm water belt, and largely corroborates the established genus and species matrix. We describe here Stephanacantha oceanica sp. nov. which closely resembles S. campaniformis, and transfer Parvicorbicula zigzag to the genus Stephanacantha, despite differences in costal strip morphology, but based on a complete agreement in lorica constructional details.     

Loricate choanoflagellates (Acanthoecida) from warm water seas. IX. Coronoeca gen. nov., Polyfibula Manton and spiny forms of Parvicorbicula Deflandre

The ambition to generate an overview of warm water loricate choanoflagellate biodiversity, based on a classic morphometric approach, is here completed by analyses of a range of tiny forms with anterior spines or projections and in most cases also a posterior pedicel. The warm water study complements previously obtained results from the more extensively studied temperate and polar regions of the world’s oceans. It thus contributes to a significantly more balanced approach to global diversity patterns for these organisms. The current survey includes taxa such as Polyfibula elatensis, Parvicorbicula pedicellata, as well as a range of primarily undescribed and taxonomically challenging species, that are in an interim approach allocated to Coronoeca gen. nov. (C. kosmaniae sp. nov., C. conicella sp. nov., C. superpositus (Booth) comb. nov., C. marchantii sp. nov., C. tongiae sp. nov., and C. patongiensis sp. nov.). The analysis of warm water acanthoecid biodiversity has revealed in total 80 species from the six geographic regions sampled, corresponding to approximately 50% of all loricate species described. Nineteen species are previously undescribed forms. The Andaman Sea, Thailand, and West Australia are in a global context the most species-rich regions with 62 and 64 species respectively.     

Loricate choanoflagellates (Acanthoecida) from warm water seas. II. Bicosta,Apheloecion, Campyloacantha,Crucispina, Calliacantha and Saroeca

The main outcome of this and subsequent papers is to provide a baseline survey of heterotrophic protist diversity from warm water marine ecosystems, exemplified by loricate choanoflagellates (Acanthoecida). Genera in focus here (i.e. Bicosta, Apheloecion, Campyloacantha, Crucispina, Calliacantha and Saroeca) possess anterior spines or projections and a posterior pedicel, and have 0, 1 or 2 transverse costae. Longitudinal costae are, with the exception of Campyloacantha, external to transverse costal elements across all genera examined here. We describe here Apheloecion eqpacia sp. nov. and Calliacantha magna sp. nov., both of which are so far distributionally confined to warm water habitats. A ‘form A’ of Bicosta minor is introduced to facilitate the distinction between B. minor sensu stricto and a presumed warm water adapted variant with a posterior lorica chamber twist of the longitudinal costae.     

Loricate choanoflagellates (Acanthoecida) from warm water seas. V. Thomsenella Özdikmen (= Platypleura Thomsen)

Loricate choanoflagellate genera that incorporate flattened costal strips in the lorica (i.e. Calotheca, Stephanacantha, Thomsenella (= Platypleura) and Syndetophyllum) are prevalent in warm water habitats. The genus Thomsenella (=Platypleura) thus comprises four species and three of these have an Andaman Sea type locality. Our ongoing examination of loricate choanoflagellate material from all major warm water oceans has provided us with the opportunity of revisiting species of Thomsenella in order to test and fortunately verify, in a morpho-specific context, the robustness of the species matrix initially defined.     

Loricate choanoflagellates of the Southern Ocean with new observations on cell division in Bicosta spinifera (Throndsen, 1970) from Antarctica and Saroeca attenuata Thomsen, 1979, from the Baltic Sea

Summary The loricate choanoflagellate Bicosta spinifera was observed frequently in Antarctic samples collected along Scotia/Weddell Sea transects. The entire population showed a conspicuous bimodal size distribution. Large forms were predominant in Scotia Sea samples, while only small specimens were found in the Confluence area. Prior to cell division Bicosta spinifera produces a complete set of costal strips in a temporary tail-like protrusion. Small specimens sometimes possess a tail similar to that found in large specimens. The fact that B. spinifera may increase considerably in size following cell division, in connection with the finding of aberrant minute forms, have prompted us to hypothesize a polymorphic life history in B. spinifera. The term caudiform division is introduced to describe division in B. spinifera. Saroeca attenuata also produces a tail prior to cell division, but is otherwise shown to undergo a mixed caudiform/tectiform type of division.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundatin     

Report on the Hippolytidae Bate (sensu lato) from China seas

Thirty species belonging to 13 genera of three families in the Hippolytidae Bate, 1888(sensu lato) are reported in the present paper, including two new species and two newly recorded ones from the China seas. The two new species are named as Thinora leptochelus sp. nov. and Thor singularis sp. nov. Thinora leptochelus sp. nov. differs from the only knwon species of the genus, Thinora maldivensis(Borradaile, 1915), by the developed supraorbital tooth and the slender and cone-shaped chelae of the first 2 pereopods. Thor singularis sp. nov. can be dinstingershed from the other members of the genus Thor by the first 2 pereopods with epipods. The two newly recorded species from China seas are Eualus kikuchii Miyake & Hayashi, 1967 and Heptacarpus commensalis Hayashi, 1979.     

A Light and Electron Microscopical Investigation of Loricate Choanoflagellates (Choanoflagellida, Acanthoecidae) from the Andaman Sea, SW Thailand and Denmark: Species of Cosmoeca gen. n.

The choanoflagellate genus Cosmoeca gen.n. is characterized by a very regular arrangement of rod-shaped costal strips, forming 9–12 longitudinal costae (each composed of 34 costal strips) and 2–3 transverse costae. Anteriorly the longitudinal costae attach the transverse costae at the joints between neighbouring transverse costal strips. Five species of Cosmoeca are described: norvegica sp.n. (type species; previously referred to as sp. "N"), C. ventricosa sp.n., (C. phuketensis sp.n., C. subulata sp.n. and C. ceratophora sp.n. Cosmoece ventricosa sp.n. is obviously part of from complex, the extent of which has not yet been fully explained. In this paper, three groups of specimens clearly related to C. ventricosa sp.n. are illustrated and briefly described ( C. ventricosa forms A. B, C). Form A appears to be identical to Pleurasiga orculaeformis Schiller, 1925, sensu Leadbeater.     

Echinococcus granulosus: In vitro effectiveness of warm water on protoscolices

Hydatid disease is one of the most important helminthic diseases worldwide. Hydatid cysts may be found anywhere in the body. The most effective treatment of hydatid cyst is surgical operation. Spillage of live protoscolices during the operation is the major cause of recurrence. Instillation of scolicidal agent into hydatid cyst is the most commonly employed measure to prevent this complication. To date, many scolicidal agents have been used for inactivation of the hydatid cyst content, however, most common scolicidal agents may cause unacceptable side-effects, limiting their use. In this study the scolicidal effect of warm water (45, 50, 55, and 60 °C) at different exposure times (1, 2, 3, 4, 5, 6, 8, 10, 12, and 15 min) is investigated. Protoscolices were collected aseptically from sheep livers containing hydatid cyst. Viability of protoscolices was determined by 0.1% eosin staining. Even though the highest scolicidal activity of warm water at 45 °C was 40.4% at the end of 15 min, the best scolicidal effect (100%) of warm water at 50, 55, and 60 °C was obtained after 5, 2, and 1 min, respectively. The results of this in vitro study showed that warm water at 50–60 °C can be regarded as an effective scolicidal agent. Warm water is commonly available, easily prepared, and inexpensive. In vivo scolicidal activity of warm water and also the possible side effects need further investigation.     

温水浸种对蒙古黄芪种子萌发特性的影响

研究温水浸种破除蒙古黄芪（Astragalus membranaceus Bge.var.mongholicus（Bge.） Hsiao）种子休眠的适宜条件,采用恒温和变温2种浸种方式,测定蒙古黄芪种子在不同时间、不同温度梯度条件下的发芽率、发芽势和发芽指数。结果表明,温水浸种破除蒙古黄芪种子休眠的效果显著,变温浸种效果略优于恒温浸种。不同温度破除休眠效果排序依次为60℃> 70℃> 80℃,其中60℃变温浸种2 min和5 min的发芽率分别为对照的2.87倍和2.31倍。浸种时间、浸种温度均可显著影响蒙古黄芪种子萌发,与对照相比,随着浸种时间增加,发芽率总体呈现出先急速升高后逐渐降低的趋势;发芽指数与浸种温度极显著正相关;浸种温度与发芽势和发芽指数均显著正相关。本研究结果表明温水浸种可以提高种子发芽率,保持种子活力。     

Ecology of the fiddler crabUca (Thalassuca) vocans vocans (Linnaeus) (Decapoda: Ocypodidae) I. Daily activity in warm and cold seasons

Field observations on the behaviour of Uca (Thalassuca) vocans vocans were made in the estuary of the Okukubi river, Okinawa Island. The formation of the feeding aggregation of wandering individuals or drove was found in warm seasons above an average monthly air temperature 20°C from April to early November, while the aggregation was little observed in cold seasons below the temperature from the middle of November to March. The members of the aggregation tended to move down from the upper levels of burrow area, rather than lower levels. This may be related to the richness of organic matters in the substratum of the lower levels as compared with the upper levels. The feeding aggregation was mostly composed of males, but in June females were numerously seen and its peak occurred in June. It suggested that the peak in June is related to both feeding and copulation. Behaviour different from warm seasons was observed in cold seasons. When feeding on surface soil or Enteromorpha the crabs carried a mass of surface soil or the alga into their burrow. It was though that this behaviour was related to the storage of food. It seems likely that the crabs maintain the population by the formation of the aggregation of wandering feeders in warm seasons when there are no algae and by feeding abundant algae as well as surface soil or by storing up food in good weather for bad one in cold seasons.     

A new transparent handy sampler for collecting water from lakes,rivers and seas

A handy sampler for collecting water from lakes, rivers and seas is described. The sampler consists of an exchangeable sample tube and a new sample-holding system. The system comprises an upper disk, a lower disk, a pair of arms with a guide pin and a semicircular arm guide with a groove. The water sample collected into the acryl tube is held without flow by a tight tube-closing system. Contamination of the sample by chemical and biological materials from the sample tube is minimized by exchanging the tube with a clean one at each sampling station. This new sampler is light, simple and useful for sampling of water from surface to bottom.     

Acanthocorbis mongolica nov. spec.: description of the first freshwater loricate choanoflagellate (Acanthoecida) from a Mongolian lake

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)cellsL(-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.     

Spatial and temporal genetic structure of the planktonic Sagitta setosa (Chaetognatha) in European seas as revealed by mitochondrial and nuclear DNA markers

Little is known about the spatial and temporal scales at which planktonic organisms are genetically structured. A previous study of mitochondrial DNA (mtDNA) in the holoplanktonic chaetognath Sagitta setosa revealed strong phylogeographic structuring suggesting that Northeast (NE) Atlantic, Mediterranean and Black Sea populations are genetically disjunct. The present study used a higher sampling intensity and a combination of mitochondrial and four microsatellite markers to reveal population structuring between and within basins. Between basins, both marker sets indicated significant differentiation confirming earlier results that gene flow is probably absent between the respective S. setosa populations. At the within-basin scale, we found no evidence of spatial or temporal structuring within the NE Atlantic. In the Mediterranean basin, both marker sets indicated significant structuring, but only the mtDNA data indicated a sharp genetic division between Adriatic and all other Mediterranean populations. Data were inconclusive about population structuring in the Black Sea. The levels of differentiation indicated by the two marker sets differed substantially, with far less pronounced structure detected by microsatellite than mtDNA data. This study also uncovered the presence of highly divergent mitochondrial lineages that were discordant with morphology, geography and nuclear DNA. We thus propose the hypothesis that highly divergent mitochondrial lineages may be present within interbreeding S. setosa populations.     

Fog interception by Sequoia sempervirens (D. Don) crowns decouples physiology from soil water deficit

Although crown wetting events can increase plant water status, leaf wetting is thought to negatively affect plant carbon balance by depressing photosynthesis and growth. We investigated the influence of crown fog interception on the water and carbon relations of juvenile and mature Sequoia sempervirens trees. Field observations of mature trees indicated that fog interception increased leaf water potential above that of leaves sheltered from fog. Furthermore, observed increases in leaf water potential exceeded the maximum water potential predicted if soil water was the only available water source. Because field observations were limited to two mature trees, we conducted a greenhouse experiment to investigate how fog interception influences plant water status and photosynthesis. Pre-dawn and midday branchlet water potential, leaf gas exchange and chlorophyll fluorescence were measured on S. sempervirens saplings exposed to increasing soil water deficit, with and without overnight canopy fog interception. Sapling fog interception increased leaf water potential and photosynthesis above the control and soil water deficit treatments despite similar dark-acclimated leaf chlorophyll fluorescence. The field observations and greenhouse experiment show that fog interception represents an overlooked flux into the soil–plant–atmosphere continuum that temporarily, but significantly, decouples leaf-level water and carbon relations from soil water availability.     

Fresh water chytrids from varanasi (India). IV. Some polycentric forms

In this paper five polycentric chytrids have been described, Nowakowskiella elegans, N. profusa, Polychytrium sp., Catenaria anguillulae and Hyphochytrium catenoides. Of the five species described, N. profusa and Polychytrium sp. are new records from India.     

Production of biogas from water hyacinth (Eichhornia crassipes) (Mart) (Solms) in a two-stage bioreactor

A two-stage rumen-derived anaerobic digestion process was tested for the conversion of water hyacinth shoots and a mixture of the shoots with cowdung (7:3) into biogas. Under conditions similar to those of the rumen and loading rates (LR) in the range of 11.6–19.3g volatile solids (VS) l–1d–1 in the rumen reactor, the degradation efficiencies were 38% for the shoots and 43% for the mixture. The major fermentation products were volatile fatty acids (VFA) with a maximum yield of 7.92mmolg–1 VS digested, and biogas with a yield of 0.2lg–1 VS digested. The effect of varying LR, solid retention time (SRT) and dilution rates on the extent of degradation of the water hyacinth–cowdung mixture was examined. Overall conversion of the substrate was highest at the loading rate of 15.4gVS.l–1d–1. Varying the retention times between 60 and 120h had no effect on the degradation efficiency, but a decrease was observed at retention times below 60h. The overall performance of the reactor was depressed by changing the dilution rate from 0.5 to 0.34h–1. By applying a LR of 15.4VS. l–1d–1, a SRT of 90h and a dilution rate of 0.5h–1 in the rumen reactor, and connecting it to a methanogenic reactor of the upflow anaerobic sludge blanket type, 100% conversion efficiency of the VFA into biogas with a methane content of 80% was achieved. The average methane gas yield was 0.44lg–1 VS digested.