Tintinnopsis Beroidea Research Articles

Community structure of tintinnids (Protozoa: Ciliophora) in the eutrophic environment (the Golden Horn Estuary, Turkey)

The distribution of tintinnid species and their associations with environmental variables were evaluated in the eutrophic Golden Horn estuary ecosystem. The samples were collected from two stations monthly between October 2009 and September 2010. The study determined 17 tintinnid species belonging to five families and nine genera. In the study, the results of environmental variables such as temperature, salinity, dissolved oxygen, pH, Secchi disk, chlorophyll-a, and nutrients were recorded synchronously with tintinnid samples. Also, the Shannon-Weaver diversity index, canonical correspondence analysis (CCA) and the two-way indicator species analysis (TWINSPAN) were applied to the data. According to this statistical analysis, the diversity was high in spring and summer, and it was determined that temperature was the main factor affecting tintinnid composition. Also, Tintinnopsis beroidea could be used as a potential indicator species in ascertaining the NH4–N, and Codonellopsis schabi and Tintinnopsis acuminata were detected to be winter and spring seasons indicators.

Spatial and seasonal variability of the planktonic ciliates assemblages along the Eastern Mediterranean Coast (Sfax coast, Tunisia)

In the present study we investigated the effects of restoration (northern coast) and anthropization (southern coast) on the spatial and seasonal distribution of ciliates communities in relation to environmental factors in coastal Sfax area. The low pH value was attributed to anthropogenic waste inputs around the southern coast. The nutrients concentrations, recorded in the southern coast, were higher than those recorded in the northern coast. Analyses demonstrated that ciliates communities’ structures showed significant differences between the northern and southern parts of the sampling coast (F = 6.54, df = 12, p < 0.001). Ciliates diversity was significantly more important in the southern coast (65 taxa) than in the northern coast (40 taxa). The ciliates abundance was 6.33 ×102±3.38× 102 cells L−1 in northern stations. The abundance of ciliates was high over the whole southern coast (12.12×102±3.78× 102 cells L−1), which increased during summer (27 × 102 cells L−1at station 1), and decreased during the spring (3 × 102 cells L−1at station 3). Tintinnids abundance was higher than naked ciliates abundance reported for all seasons, both in the north and south Sfax coast. Some tintinnids species, like Tintinnopsis beroidea, Tintinnopsis nana and Tintinnopsis parvula attained important abundance in the southern area, because they are able to survive under adverse conditions owing to its adaptive strategies. Tintinnidium balechi was a dominant and common species, with high occurrence and represented an important contributor to the ciliate communities. Pearson’s correlation coefficients showed that the seasonal ciliates variations were significantly correlated with nutrients (total nitrogen with tintinnids and orthophosphate plus total phosphate with naked ciliates).

The type species of Amphorellopsis and Tintinnopsis (Protozoa:Ciliophora): A new ciliary pattern and some comments in Tintinnina

BackgroundAs dominant components of planktonic microeukaryotes, the tintinnine ciliates act as a trophic link between microbial food web and traditional planktonic food chain in aquatic ecosystems. However, traditionally the taxonomy and systematics of tintinnines have been based on the lorica. It is now accepted that lorica features alone are insufficient and that cytological and molecular information are also needed. The systematics of the genera Tintinnopsis and Amphorellopsis is ambiguous, mainly due to the lack of ciliary and molecular information on their type species, T. beroidea and A. acuta. ResultIn the present study, specimens of both species were collected from coastal waters of Qingdao, China. The morphology of each was investigated based on observations of live and protargol-stained specimens, and their SSU rDNA- and LSU rDNA-based phylogenies were analyzed. Tintinnopsis beroidea presents the genus-typical ciliature. The somatic kineties in Amphorellopsis acuta were found to be evenly distributed without differentiation into distinct ciliary fields. The phylogenetic analyses revealed that Tintinnopsis is non-monophyletic, and that T. beroidea has a close relationship with T. nana and T. baltica. The monophyly of Amphorellopsis is also not supported by SSU rDNA analysis. ConclusionThis study first reveals the ciliary pattern and two nuclear rRNA gene sequences of two tintinnine type species, and thus expands knowledge and database of tintinnines. Amphorellopsis represents an intermediate lineage between tintinnines (loricate form) and aloricate choreotrichids.

Spatial and temporal variations of tintinnids (Ciliata: Protozoa) in the Bay of Mersin, Northeastern Mediterranean Sea

Seasonal variations in species composition and abundance of tintinnids were investigated in the eutrophic coastal and offshore waters of Mersin Bay. Twelve sampling cruises were performed from September 2008 to February 2011. A total of 85 tintinnid taxa were identified. Among the recorded genera, agglutinated Tintinnopsis had the largest number of species (12 species), followed by hyaline loricated Eutintinnius (9 species), and Proplectella (7 species). Stenosemella ventricosa, Tintinnopsis beroidea, T. compressa, Favella azorica, and Helicostemella subulata were the dominant species during the study period. There were clear seasonal variations in species composition and abundance of tintinnids. The highest number of tintinnid species occurred in January 2009 and November 2010 in the entire study area, while the lowest species number occurred in March 2009. Morever, species numbers were higher in offshore stations than coastal stations. Some species were present in the coastal area of the bay, and other species were present offshore. The highest tintinnid abundance values were found in September 2008 (820 ind L-1) and August 2009 (749 ind L-1) at coastal stations. The high abundance values in the coastal stations indicates that an increase of tintinnids is closely related to trophic status of the marine environment. In connection with these results, correlation analysis revealed that chlorophyll-a had an important effect on tintinnid abundance. Tintinnid communities may be used as a potential bio-indicator for assessing the trophic state of the coastal seas and bays.

Plankton ciliate community responses to different aquatic environments in Nan'ao Island, a representative mariculture base in the South China Sea

The temporal variation and spatial distribution of plankton ciliate communities were investigated in Shen’ao Bay, South China Sea. In all, 35 species belonging to 17 genera and 7 orders were identified. The number of ciliate species was lower in spring than in summer, whereas ciliate abundance was higher in spring than in summer. Spatially, the number of ciliate species and ciliate abundance were higher in the oyster–algae mixed culture area and non-aquaculture area, and lower in the caged fish culture area. Multivariate and univariate analyses demonstrated that ciliate communities were associated with environmental factors (e.g. temperature, chlorophyll (Chl)-a, nutrient levels). In addition, two dominant species, namely Mesodinium rubrum and Tintinnopsis beroidea, were significantly positively correlated with Chl-a. Three dominant species, namely Strombidium globosaneum, Tintinnopsis minuta and Strombidium conicum, showed more sensitivity to dissolved oxygen, pH and chemical oxygen demand, whereas Tintinnopsis parvula and Tintinnopsis chinglanensis were significantly related to NO2–. Ciliate species diversity, species evenness and species richness were higher in the oyster–algae mixed culture area and non-aquaculture area and lower in the caged fish culture area. Therefore, the results of this study suggest that the ciliate community is significantly correlated with its aquatic habitat and the dominant species can be considered a favourable bioindicator of the marine water environment.

Loricate ciliates as an indicator of eutrophication status in the estuarine and coastal waters

Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems.

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Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems.

Environmental impact on diversity and distribution of tintinnid (Ciliata: Protozoa) along Hooghly Estuary, India: A multivariate approach

The spatiotemporal distribution, diversity and biomass of the choreotrich ciliate tintinnid, the ubiquitous planktonic protist, were analysed from nine sampling sites (n=252) of diverse environmental stresses along the Hooghly Estuary, eastern part of India during March 2012 to August 2014. Among 32 identified tintinnid species, the agglomerated genera Tintinnopsis (20 sp), dominated the community (∼62%) followed by Tintinnidium (2 sp), Leprotintinnus (2 sp), Codonellopsis, Stenosemella, Helicostomella, Favella, Eutintinnus, Metacylis, Dadayiellaand Wangiella (each comprising single species). A wide range of seasonal variations in tintinnid abundance was recorded maximum (2067±893 ind. l−1) for Tintinnopsis beroidea and minimum (11±4 ind. l−1) for Metacylis sp. during the investigation period. The biomass and daily production rate of tintinnid ranged from 0.004–2.764 μg C l−1 and 0.04–3.54 μg C l−1 day−1 respectively. An overall dominance and diversity of the small-sized tintinnid (lorica length <76 μm) belonging to the genera Tintinnopsis sp., Tintinnidium sp., Codonellopsis sp., Wangiella sp., Eutintinnus sp., Metacylis sp. and Helicostomella sp. was pronounced, accounting ∼66% of the total tintinnid abundance. K-dominance curves were plotted against log rank k, showed species dominance over the investigated sites. The multidimensional scaling (MDS) Canonical Analysis of Principal coordinates (CAP) highlighting a significantly different spatial distribution of tintinnid. Principal Component Analysis (PCA) map showed clustering of core species with chl a and nitrate and could be considered as the crucial factors controlling the distribution and seasonal patterns of tintinnid. Biota-environment (BIOENV) analyses also reveal that these two parameters were the significant causative factors, suggesting that tintinnid may be used as a bioindicator for discriminating water quality in this estuarine system. The study provided detailed information of microzooplankton which enhances our understanding regarding its crucial role in marine ecosystem and complex biotic interactions for maintaining the ecological and economic stability.

Using ciliates to monitor different aquatic environments in Daya Bay, South China Sea

Spatial patterns of planktonic ciliate communities were studied to monitor marine water quality during winter, spring, summer, and autumn of 2014 in Daya Bay, South China Sea. A total of 41 species, with eight dominant species, were identified. Multivariate and univariate analyses demonstrated that spatial taxonomic pattern of planktonic ciliate communities was significantly correlated with environmental condition; ciliate abundance, species diversity, and species richness were significantly correlated with NO3– and salinity or temperature. Additionally, two dominant species (Tintinnopsis minuta Wailes, 1925 and Tintinnopsis beroidea Stein, 1867) were significantly positively correlated with nutrients, particularly with nitrogen nutrients. Three dominant species (Strombidium conicum (Lohmann, 1908) Wulff, 1919; Spirotontonia turbinata (Song &amp; Bradbury, 1998) Agatha, 2004; Laboea strobila Lohmann, 1908) showed more sensitivity to salinity, whereas Mesodinium rubrum (Lohmann, 1908) was significantly correlated with temperature. Our findings suggest that planktonic ciliate communities can be considered a favorable bioindicator of marine water quality.

Choreotrich ciliate tintinnid (Protozoa: Ciliophora) in a tropical meso–macrotidal estuary, eastern part of India

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.

2010年春季长江口及邻近海域砂壳纤毛虫的分布特点

于2010年春季(5月)在长江口及邻近海域进行砂壳纤毛虫丰度和生物量的调查。砂壳纤毛虫的丰度范围为0~1362 ind/L，平均丰度为226 ± 243 ind/L；砂壳纤毛虫的生物量范围为0.00~5.97 μg C/L，平均生物量为0.54 ± 0.86 μg C/L。表、中和底层砂壳纤毛虫丰度和生物量的高值区一般分布在长江口外海域的中部；砂壳纤毛虫丰度和生物量均在表层达到最高值，随水深增加明显降低。共鉴定出砂壳纤毛虫9属22种，其中拟铃虫属(Tintinnopsis)种类最多。主要优势种为百乐拟铃虫(Tintinnopsis beroidea)、黏粘筒壳虫(Tintinnidium mucicola)和白领细壳虫(Stenosemella nivalis)。砂壳纤毛虫群落Shannon指数的平均值为1.05 ± 0.59，Pielou指数的平均值为0.66 ± 0.33。砂壳纤毛虫群落水体Shannon指数和Pielou指数的高值区主要分布在长江口外海域。 We investigated the abundance and biomass of tintinnids in the Changjiang Estuary and adjacent areas in spring of 2010. The average abundance of tintinnids was 226 ± 243 ind/L, ranging from 0 to 1362 ind/L. The average biomass of tintinnids was 0.54 ± 0.86 µg C/L, ranging from 0.00 to 5.97 µg C/L. High value areas of tintinnid abundance and biomass were mainly distributed in the middle area off the Changjiang Estuary. Tintinnids tended to accumulate in the surface layer. Twenty two tintinnid species were identified, 11 of which were in genus Tintinnopsis. The most dominant species were Tintinnopsis beroidea, Tintinnidium mucicola and Stenosemella nivalis. The average Shannon index and Pielou index were 1.05 ± 0.59 and 0.66 ± 0.33, respectively. The Shannon index and Pielou index were higher in the area off the Changjiang Estuary.

Spatial and seasonal variations of large tintinnid ciliates in Shenhu Bay of China

AbstractIn this study, the spatial distribution and seasonal variation of large tintinnids (&gt;76 μm) were investigated in Shenhu Bay during three seasons of 2012. Of the 36 species identified, 9 were dominant (i.e. Tintinnopsis radix, Leprotintinnus simplex, Tintinnopsis japonica, Tintinnopsis tubulosoides, Leprotintinnus nordqvisti, Tintinnopsis beroidea, Stenosemella parvicollis, Tintinnidium primitivum, Tintinnopsis nana). A clear seasonal shift of the taxonomic composition as well as the lorica size of the dominant species was observed. The highest numbers of tintinnid species occurred in spring, while the highest abundance and biomass occurred in summer. Clustering indicated that the seasonal variations of the community structure were more obvious than spatial variations. Spearman correlation analysis revealed that density of phytoplankton prey had a significant impact on the tintinnid abundance. Redundancy analysis (RDA) illustrated that temperature, salinity and the nutrient level were the most important abiotic factors affecting the spatial and seasonal pattern of tintinnid communities in Shenhu Bay.

Protozoa in a stressed area of the Egyptian Mediterranean coast of Damietta, Egypt

The Damietta coast is part of the Egyptian Mediterranean coast off the Nile Delta and has recently been polluted as a result of intensive human activities. The environmental parameters and protozoan community in the area were studied biweekly from January to December 2007. The results of the environmental parameters indicated low salinity, oxic and anoxic conditions, high nutrient levels and intensive phytoplankton growth. A total of 69 protozoan species were identified, belonging to Amoebozoa (8 species), Foraminifera (12 species), non-tintinnid ciliates (22 species) and tintinnids (27 species). The numerical density of protozoans was high over the whole area, with annual averages between 8.2×103 cells m−3 and 51.4×103 cells m−3. Spring was the most productive season for protozoans, but several distinct peaks were observed during the year at the sampling sites. The protozoan groups showed clearly different spatial patterns in both composition and abundance: whereas amoebozoans and non-tintinnid ciliates were dominant in the more polluted areas (sites IV and V), tintinnids dominated in the less polluted areas (sites, I, II and III). Several pollution indicators were recorded: amoebozoans – Centropyxis aculeata, Centropyxis sp., Cochliopodium sp., Difflugia sp.; non-tintinnids – Bursaridium sp., Frontonia atra, Holophrya sp., Paramecium sp., Paramecium bursaria, Vasicola ciliata, Vorticella sp., Strombidium sp.; tintinnids – Favella ehrenbergii, Helicostomella subulata, Leprotintinnus nordgvisti, Tintinnopsis beroidea, Stenosemella ventricosa, Tintinnopsis campanula, T. cylindrica, T. lobiancoi, Eutintinnus lusus-undae.

Phylogenetic investigation on five genera of tintinnid ciliates (Ciliophora, Choreotrichia), based on the small subunit ribosomal RNA gene sequences

The phylogenetic relationship among tintinnid ciliates are relatively poorly studied based on molecular data. In the present work, seven species belonging to five genera of the order Tintinnida ( Amphorellopsis acuta, Codonellopsis nipponica, Favella taraikaensis, Stenosemella nivalis, Tintinnopsis beroidea, Tintinnopsis cylindrica and Tintinnopsis lohmanni) were analyzed using the information on their small subunit ribosomal RNA gene sequences. Phylogenetic trees were constructed using Bayesian inference (BI), maximum parsimony (MP), neighbor-joining (NJ), and least-squares (LS) methods. Generally, similar topologies were revealed with high or moderate supports, in which the main results show that (1) all tintinnids analyzed belong to a single assemblage; (2) congeners in Tintinnopsis do not cluster together, which indicates that the lorica-based definition for this genus is not consistent with the SSU rRNA phylogeny; (3) A. acuta groups with Tintinnidium mucicola but not with Eutintinnus, indicating that the traditional family Tintinnidae might be a paraphyletic group; (4) Stenosemella and Codonellopsis are clearly most related and possibly even merged into one genus regarding their similar morphology and molecular analyses, and possession of a hyaline collar is the only characteristic of the genus.

Fast microzooplankton grazing on fast-growing, low-biomass phytoplankton: a case study in spring in Chesapeake Bay, Delaware Inland Bays and Delaware Bay

Dilution experiments were performed to examine the growth and grazing mortality rates of picophytoplankton ( 20 μm) at stations in the Chesapeake Bay (CB), the Delaware Inland Bays (DIB) and the Delaware Bay (DB), in early spring 2005. At station CB microphytoplankton, including chain-forming diatoms were dominant, and the microzooplankton assemblage was mainly composed of the tintinnid Tintinnopsis beroidea. At station DIB, the dominant species were microphytoplanktonic dinoflagellates, while the microzooplankton community was mainly composed of copepod nauplii and the oligotrich ciliate Strombidium sp. At station DB, nanophytoplankton were dominant components, and Strombidium and Tintinnopsis beroidea were the co-dominant microzooplankton. The growth rate and grazing mortality rate were 0.13–3.43 and 0.09–1.92 d−1 for the different size fractionated phytoplankton. The microzooplankton ingested 73, 171, and 49% of standing stocks, and 95, 70, and 48% of potential primary productivity for total phytoplankton at station CB, DIB, and DB respectively. The carbon flux for total phytoplankton consumed by microzooplankton was 1224.11, 100.76, and 85.85 μg C l−1 d−1 at station CB, DIB, and DB, respectively. According to the grazing mortality rate, carbon consumption rate and carbon flux turn over rates, microzooplankton in study area mostly preferred to graze on picophytoplankton, which was faster growing but was lowest biomass component of the phytoplankton. The faster grazing on Fast-Growing-Low-Biomass (FGLB) phenomenon in coastal regions is explained as a resource partitioning strategy. This quite likely argues that although microzooplankton grazes strongly on phytoplankton in these regions, these microzooplankton grazers are passive.

ECOLOGICAL INVESTIGATION OF THE TINTINNID COMMUNITY ALONG THE COASTAL WATERS OF ALEXANDRIA, EGYPT

The distribution of the tintinnid assemblages was studied in samples collected from 2 areas subjected to primary treated sewage flow and agricultural/industrial mixed discharge along the coastal water of Alexandria during summer 1999 and winter 2000. During the entire investigation, the protozoopiankton were numerically dominated by tintinnids with densities ranging between 26 and 9464 Ind./m . Distinct differences that appeared in the patterns of occurrence and numbers of the tintinnids in those locations, were attributed to different physical and chemical conditions. Tintinnid assemblages were represented by 19 species, the most dominant of which were: Tintinnopsis beroidea, Favella ehrenbergii, Eutintinnus macilentus and Tintinnopsis campanula. Two freshwater tintinnids appeared at the near-shore locations of El-Mex Bay during high flow when salinity reached 9 psu.

Abundance and species composition of Tintinnina (ciliophora) in Bahía Blanca estuary, Argentina

Numerical abundance and seasonal cycle of tintinnines species were studied in the inner part of the Bahía Blanca estuary. Sampling was carried out at two fixed stations at approximately weekly intervals over the period March 1986-February 1987. Nineteen species representing five genera were recorded. Most species belonged to the genus Tintinnopsis . Maximal abundances of tintinnines, 10·1 × 10 3 1 −1 and 11·3 × 10 3 1 −1 at each station respectively, were found in summer. Minimal abundances, 0·5 × 10 3 1 −1 and 0·7 × 10 3 1 −1 at each station respectively, were found in winter. Tintinnidium balechi, Tintinnopsis parva and Tintinnopsis glans were present throughout the year. Tintinnopsis gracilis, Tintinnopsis baltica and Tintinnopsis beroidea exhibited seasonal occurrence, the remaining species did not show a clear pattern of distribution. The presence of Favella taraikaensis demonstrated occasional intrusions of typical fauna of the outer estuary.

Mass occurrence of planktonic oligotrichous ciliates in a bay in southern Norway

A reddish-brown discoloration of the surface water in Flødevigen Bay, southern Norway on May 15, 1985 was due to planktonic oligotrichous ciliates occurring in densities of 2079 cells ml −1 . Strombidium reticulatum (Leegaard, 1915) Bush, 1921 and Tintinnopsis beroidea Stein, 1867 accounted by numbers for 59.7 and 35.1% respectively. Both the build-up and decline were probably mainly due to wind-induced hydrographical conditions. No fish mortalities were reported.

Feeding of field collected tintinnid micro-zooplankton on natural food

The ingestion and filtration rates of seven species of field collected tintinnids, Tintinnidium fluviatile (Stein), Helicostomella subulata (Ehrenberg), Tintinnopsis parva (Merkle), Tintinnopsis beroidea (Stein), Tintinnopsis vasculum (Meunier), Tintinnopsis acuminata (Daday) and Stenosemella oliva (Meunier), feeding on natural particle suspensions were measured. Ingestion rates of 0.05×106 μm3 to 1.3×106 μm3 tintinnid-1 d-1 were observed with corresponding maximum filtration rates of 2 to 65 μl tintinnid-1 h-1. Filtration rates (among species) were independent of temperature and highest rates were associated with larger food particles. The filtration rates observed in this study were equal to rates reported for tintinnids feeding on cultured algae when natural food sizes equivalent to those of the cultured algae were considered, but were sometimes higher when the entire spectrum of natural food was considered. Size specific ingestion rates indicated maximum food removal from biomass peaks with filtration effort generally maximized on the largest sized food a species could handle. A strong negative relationship exists between weight specific ingestion and filtration rates and body weight. When tintinnid ingestion rates are considered, along with rates for other invertebrates, as a function of body weight, a log log linear relationship is found for body weights ranging from 0.8 ng to 1 kg. Tintinnids exhibited saturation feeding responses when presented with several concentrations of natural food up to in situ.

Cultivation of marine ciliates (Tintinnida) and heterotrophic flagellates

1. Five species of heterotrophic Protozoa are presently under investigation in this laboratory. They are: the tintinnid,Tintinnopsis beroidea, 2 species of dinoflagellate,Cryptothecodinium cohnii andNoctiluca scintillans, and the choanoflagellatesDiaphanoeca grandis andAcanthoecopsis sp. 2. Their nutritional status and some potential applications are discussed, along with some observations on other tintinnids previously cultured.