relating to position, away from the oral apparatus. cf. adoral.
the formula describing thecal plate orientation in armoured dinoflagellates.
spindle- or needle-shaped.
of a flagellum, terminating in a narrow hair-point.
a ray-shaped pseudopodium.
relating to position, near the oral apparatus. cf. aboral.
(of ciliates), lorica wall composed entirely of foreign particles which are added during construction and held together by an organic cement.
(of ciliates), type of brosse; orientation is parallel to somatic kineties and these are not inclined upon the brosse.
(of prasinophytes), Pterosperma, a wing-like projection on the outer surface. pl. alae.
without a lorica.
(of diatoms), an elongated chamber running from the central part of the valve to the margin, open to the inside and covered by a perforated layer on the outside. pl. alveoli.
Antarctic Marine Ecosystems Research in the Ice Edge Zone, 1983, 1986 and 1988 expeditions to the Weddell and Scotia Seas (see Garrison & Buck, 1989a).
a member of the Class Lobosea; a protist that uses pseudopodia. pl. amoebae.
(of armoured dinoflagellates), plates composed of cellulose or other polysaccharide microfibrils binding the cell.
having flagella of unequal length and/or characteristics; usually one flagellum with flagellar hairs, the other smooth.
(of diatoms), a ring of costal thickness, often surrounding one or more processes and with a structure different from that of the rest of valve. adj. annulated.
lacking oxygen. cf. oxic.
the posteriormost part of cell body excluding spines and similar structures.
that part of the organism which leads in forward movement.
an opening; used in relation to loricae or tests to indicate the site of emergence of the flagella or pseudopodia; of diatoms, the space between adjacent valves of a chain.
the anteriormost part of a cell.
perpendicular to the transapical axis.
(of diatoms), used mainly for cells in stellate, radiating and bundle-shaped colonies in which neighbouring cells are joined by valve faces of the antapical poles. The apical pole is the tip of the other end of the cell. cf. antapical pole.
(of diatoms), an area of small pores at the apices of the valves, usually in longitudinal rows.
(of diatoms), an area of elongate pores (slits) at the apices of the valves, usually in longitudinal rows.
curved like a bow.
(of diatoms and dinoflagellates), ornamentation in the form of deep or shallow depressions on thecal plates or valves.
an organism that can manufacture its own organic requirements from inorganic materials independent of other sources of organic substrata. adj. autotrophic; cf. heterotroph, mixotroph.
a photosynthetic organism that requires only supplementary organic substances (e.g. vitamins). adj. auxotrophic.
(of coccolithophores), a structure spanning the central area of a coccolith, with longitudinal and transverse cross-bars, e.g. in Pappomonas weddellensis, and Papposphaera spp.
a conceptual line passing through specified parts of a cell.
the group of microtubules (9 × 2 + 2 structure) constituting the active part of the flagellum.
(of a centrohelid heliozoan), a thin, straight pseudopodium with an internal skeletal structure comprising microtubules.
(of diatoms, Family Chaetoceraceae), that portion of a seta closest to the valve face; that portion of an inner seta between its point of origin on valve face and its point of crossing with its sibling setae.
(of diatoms), a layer that forms the basic structure of the various components of the frustule.
(of coccolithophores), a body coccolith (e.g. in Pappomonas).
Expédition Antarctique Belge, voyage of S.Y. Belgica, 1897-99, western Antarctic Peninsula.
referring to organisms living on the sea-bed.
having two adjoining bow-like curves.
forked, divided into two parts.
(of diatoms), a process consisting of an shorter or longer external tube, sometimes reduced to a low ring (LM), and an internal part with a longer or shorter stalk and a trapezoidal end-piece closed at the tip but open at each of the two slanting sides by a longitudinal split.
an asexual mode of reproduction.
the living space of a community of organisms (plants, animals and microorganisms).
an overabundant growth of organisms, often caused by nutrient enrichment.
members of the Class Cyanophyceae.
Norwegian Antarctic Expedition, 1947-48.
(of ciliates), stiff and rather immobile cilia (long or short) of several kinds and functions.
(of ciliates), see oral apparatus.
(of coccolithophores), a flaring structure at the tip of a process, e.g. in Papposphaera spp.
(of Granuloreticulosa), latticed.
(of coccolithophores), a disc- or bowl-shaped heterococcolith with a lath-filled central area (e.g. in Syracosphaera).
having a knob-like head or tip.
(of ciliates), relating to or in the position of a tail.
(of diatoms, Family Bacillariaceae), a pore-like expansion of the central raphe ending.
referring to diatoms of the Order Centrales.
a type of heliozoan with thin, parallel-sided arms with prominent extrusomes.
(of coccolithophores), a circum-flagellar coccolith (e.g. in Pappomonas).
(of diatoms), cells joined by threads from strutted processes (Thalassiosira), by external parts of strutted processes (Skeletonema), by abutting of valve faces (Leptocylindrus), by external part of the single labiate process, contiguous area and claspers (Rhizosolenia), by bipolar elevations (Eucampia), by bipolar elevations with spines (Ceratulina), by setae (Chaetoceros) or by a marginal ridge (Lithodesmium).
a group of green pigments having the vital function of absorbing light energy for photosynthesis.
a member of the Class Chlorophyceae.
a member of the Class Craspedophyceae/Choanoflagellida.
an assemblage of molecular DNA in the nuclei of eukaryotic cells, containing genetic information.
a member of the Class Chrysophyceae.
a member of the Phylum Ciliophora.
the total assembly of oral and somatic cilia or cirri; may be arranged in patches, kineties, membranes or membranelles.
(of ciliates), bearing cilia.
(of ciliates), a hair-like projection associated with locomotion, having a 9 × 2 + 2 axonemal arrangement as found in flagella. pl. cilia.
(of dinoflagellates), a furrow encircling a dinoflagellate cell once or several times, either circular, displaced, median, postmedian or premedian in location; of diatoms, a portion of a diatom girdle associated with a single valve; part of the frustule between upper and lower valves. adj. cingular.
(of dinoflagellates), a cingulum that is not displaced and in which the proximal end meets the distal end.
(of ciliates), surrounding the oral area.
(of diatoms), Family Rhizosoleniaceae, a pair of membranous structures that unite adjacent cells by wrapping around the otaria.
a cell with a firm outer wall, without flagella.
plate-like, calcified scales formed in vesicles of the endoplasmic reticulum of coccolithophorid haptophytes.
a member of Order Coccolithophorales.
a localised population of organisms derived from a single cell.
(of diatoms), an element in the middle of the girdle when intercalary bands are present, or any element when intercalary bands are absent.
see intercalary band, girdle band.
(of ciliates), small, often refractile granules in the periphery of a cell, sometimes corresponding to extrusomes (e.g. mucocysts). Colour, shape and arrangement are important species characteristics.
(of tintinnid ciliates), lorica shape as in genus Coxliella.
with a regularly indented margin.
(of coccolithophores), a minute crystal.
a member of the Class Cryptophyceae.
a member of the Class Cyanophyceae.
(of ciliates), a type of subpellicular extrusome found in Didinium.
(of ciliates), a type of tubular cytopharyngeal apparatus; often curved, with walls strengthened by longitudinally arranged nematodesmata. Derived from apically located kinetosomes and lines with extensions of postciliary microtubules; does not contain toxicysts.
a bladder or bag-like structure that may contain the resting stage of an organism.
in alternating pairs.
fragments of dead biological material before, during and after decay, sometimes incorporating inorganic matter.
a member of the Class Diatomophyceae/Bacillariophyceae.
(of ciliate)s, a morphological complex of two neighbouring (paired) basal bodies (kinetosomes) along with associated cilia and infraciliary organelles.
a member of the Class Dinophyceae.
(of coccolithophores), cells having two discrete layers of different types of coccoliths, the endothecal and exothecal layers.
the uppermost side, or back, of an organism.
(of euplotid ciliates), a type of dorsal silverline system; one longitudinal silverline in the middle between each of two dorsal kineties connected with transverse silverlines so that two longitudinal rows of equally long rectangles are formed.
(of euplotid ciliates), a type of dorsal silverline system; one longitudinal silverline eccentric between each of two dorsal kineties connected with transverse silverlines so that two longitudinal rows of unequal rectangles (one large, one very small) are formed.
living on the surface of and in close association with another organism of a different species where neither has an obvious effect on the other. cf. endocommensal.
(of diatoms, Family Eupodiscaceae), a raised portion of a valve wall, not projecting laterally beyond the valve margin, which may bear some special structure; otherwise with the same structure as valve.
U.S.A. Oceanographic Research Ship Eltanin, Cruise 38, Southern Ocean, south of Australia, 1969.
living inside another organism of a different species where neither has an obvious effect on the other. cf. ectocommensal.
(of ciliates), a row of cilia extending on the bottom and right border of the oral cavity.
an organism living within a dissimilar organism in a relationship in which both partners benefit. adj. endosymbiotic.
(of ciliates), an intimate (transitional) association between two organisms (usually animals) in which one partner lives within the host body to obtain shelter but without parasitising it. adj. entoecic.
an organism that grows attached to the outside of another living organism.
a plant that grows attached to the outside of another plant, using it only for support, but doing it no harm.
an organism that grows attached to the outer surface of an animal.
equal in size and form.
Endoplasmic Reticulum, a series of interconnected, flattened, subcellular cavities.
Royal Society (London) Expedition Ship Erebus, Antarctic expeditions of 1839-43, commanded by James Clarke Ross.
a member of the Class Euglenophyceae.
of crystals, characterised by well-developed crystal faces (external surfaces).
any cell or organism comprised of cells that possess a membrane-bound nucleus, several chromosomes, cellular organelles and accomplishes cell division by mitosis and meiosis. adj. eukaryotic; cf. prokaryote.
(of ciliates), a membrane -bound, subpellicularly located extrusible body of various, probably non-homologous types (e.g. cyrtocysts, mucocysts, pexicysts, toxicysts, trichocysts).
(of ciliates, Genus Loxophyllum), protruding, wart-like structures along dorsal margin containing groups of extrusomes (toxicysts).
a pigmented, light-sensitive organelle.
(of diatoms), valve striae (and, therefore, areolae) grouped in discrete sectors (fascicles).
a small, window-like perforation. pl. fenestrae; adj. fenestrated.
material treated with a histological stain selective for DNA.
First International Biological Experiment; international research cruise, 1981, Southern Ocean between Mawson and Davis Stations.
(of diatoms, Family Bacillariaceae), an internal bridge of silica subtending the raphe. pl. fibulae.
(of amoebae), a filiform pseudopodium with a pointed tip, capable of rather rapid movement, used for locomotion and food uptake.
(of amoebae), of the Class Filosea.
a type of feeding in which suspended particles are concentrated and ingested by means of cilia or flagella directing a current of water to the cell, and a filter to trap and concentrate the particles before enclosure within a food vacuole.
(of dinoflagellates), a pore through which a flagellum emerges.
a fine, whip-like process associated with locomotion, normally with the typical 9 × 2 + 2 microtubular arrangement of the axonemes. pl. flagella; adj. flagellar, flagellate, flagellated.
(of chrysophytes), minute tubular hairs along all or part of the flagellar axis.
see antapical pole; cf. apical pole, head pole.
(of prasinophytes), a minute, organic body scale in the shape of a human footprint.
a material for producing very thin films for supporting material on electron microscope grids.
the silica-containing wall of a diatom.
swollen at the middle and tapering towards each end; narrowly ellipsoidal.
German South Polar Expedition aboard the Gauss, 1901-03, Davis Sea (see Heiden & Kolbe, 1928).
bent like a knee.
(of diatoms), part of a frustule between the upper and lower valves; of strombidiid ciliates, referring to transverse orientation.
see intercalary band, copula.
a vegetative or gametic organism in which the nucleus contains one set of chromosomes. abbrev. n/1n.
(of haptophytes), an organelle formed as a microtubular appendage, serving as a holdfast or for crawling or food uptake.
a member of the Class Haptophyceae.
see apical pole; cf. antapical pole, foot pole.
(of coccolithophores), a placolith with a spiral pattern and marginal flange which overlaps adjacent helicoliths (e.g. Helicosphaera carteri).
of an organism that feeds exclusively on plant material. n. herbivory.
flagella that have independent patterns of beating. cf. homodynamic flagella.
(of dinoflagellates), biflagellate, with one smooth flagellum and the other covered with mastigonemes.
(of diatoms), cells having morphologically different poles (apices). cf. isopolar.
an organism that is dependent on obtaining organic food from the environment due to its inability to synthesise organic material. adj. heterotrophic; cf. autotroph, mixotroph.
(of diatoms), cells having morphologically different valves. cf. isovalvate.
the basal part of an organism attaching it to the substratum.
(of ciliates), having the entire body completely and ±uniformly ciliated.
flagella that have the same pattern of beating. cf. heterodynamic flagella.
colourless and transparent.
(of diatoms), an element of a girdle lacking perforations.
(of diatoms, Family Asterolampraceae), raised openings in the valve face, open to the interior of the valve by elongate, slit-like openings, open to the exterior through holes at the marginal ends of the rays.
in vivo :
in reference to a living organism.
(of ciliates), the total assembly of somatic and oral basal bodies and their associated subpellicular microfibrillar and microtubular structures.
(of diatoms), the non-perforate, siliceous strips between two striae. pl. interstriae; adj. interstrial.
inpushing of a layer of cells; or a concave structure (e.g. cell surface, oral area) in unicellular organisms.
a covering or coating.
(of diatoms), cells having morphologically identical poles (apices). cf. heteropolar.
(of diatoms), cells having morphologically identical valves. cf. heterovalvate.
a permanent sampling station during 1992-95, south-west of Kerguelen Is., near the Polar Front at 50°40'S 68°25'E.
(of ciliates and flagellates), basal apparatus of cilia and flagella, consisting of at least one kinetosome with all associated rootlets (monokinetid), but also of two (dikinetid) or more kinetosomes (polykinetid).
(of ciliates), a subpellicularly located basal termination of cilia, cylindrical and composed of 9 peripheral microtubular triplets; may be non-ciliferous.
(of ciliates), a structurally and functionally integrated row of single or paired somatic kinetids, often running longitudinally.
in reference to the final chamber of a whorl being reduced in size.
(of diatoms), a tube or an opening through the valve wall with an internal flattened tube or a longitudinal slit surrounded by two lips.
(of coccolithophores), elements and sutures that curve to the left when traced radially outward, e.g. in Calcidiscus leptoporus.
(of ciliates), a layer. adj. laminal.
narrow with curved sides tapering to a pointed end.
of, at, towards or from the side.
(of coccolithophores), a thin strip of crystalline structure.
the continuum of phases and cell types in the growth and reproduction of an organism.
a small, tongue-like projection on diatom copulae. pl. ligulae.
(of prasinophytes), a minute, organic body scale in the shape of a horseshoe crab.
(of diatoms, Family Fragilariaceae), marginal spines that link sibling valves in a chain.
a membranous extension of an armoured dinoflagellate.
(in amoebae), a lobe-like pseudopodium with a rounded termination, used for locomotion and food uptake.
swollen, with a small, nipple-like projection.
a hair-like projection of the flagellar shaft.
(of dinoflagellates), a cingulum located approx-imately at the midpoint of the cell.
a thin sheet of organic material in protists, plants and animals.
(of ciliates), a compound structure comprising many cilia, and associated with the mouth of a ciliate; present either in groups of 3 or as a band of many more.
plankton organisms in the size range 200-2000 µm. adj. mesoplanktonic.
mobility and the ability to change the shape of the cell.
Indian Ocean Expedition of R.V. Meteor, 1964-65 (see Simonsen, 1974).
a unit of length equivalent to 10-6 of a metre. abbrev. µm.
(of ciliates and foraminiferans), a small, germline nucleus that shows little or no gene expression, but with the potential to undergo meiosis; found in cells exhibiting nuclear dimorphism. cf. macronucleus.
plankton organisms in the size range 20-200 µm. adj. microplanktonic.
a thin, proteinaceous tubule acting as a supporting, cytoskeletal element within protist cells.
(of spirotrich ciliates), a usually longitudinal row of cirral pairs in a zig-zag arrangement ±along the median of a cell.
a cylindrical, subcellular organelle found in eukaryotes, containing some DNA and the enzymes required for metabolic processes. pl. mitochondria.
an autotrophic organism taking up organic substances for supplementary nutrition (e.g. by phagotrophy), or a heterotroph with ingested chloroplasts supplem-enting nutrition. adj. mixotrophic.
(of ciliates), the derived formation of unpaired individual kinetids.
single-layered, usually only one cell thick.
an organism with a variation in form or structure from the type specimen, but considered to be circumscribed within the same species.
moving, e.g. by swimming, gliding, crawling, kicking or pulsating.
a heterococcolith with an elevated rim but without a well-developed shield, e.g. Syracosphaera pulchra.
a unit of length equivalent to 10-9 of a metre. abbrev. nm.
plankton organisms in the size range 2-20 µm. adj. nanoplanktonic.
a frustule seen from the narrow side.
(of dinoflagellates), an ejectile organelle, often arranged radially or subradially in the cell (e.g. in Polykrikos).
(of ciliates), a rod-like, microtubular bundle arising from the distal side of neighbouring kinetosomes and cross-linked, often in a hexagonal pattern. pl. nematodesmata.
a very thin, grey, elastic type of ice with a matt surface which is readily bent by wave action.
not able to contract.
(of diatoms), a small, siliceous thickening in the valve wall, usually with a thickened, structureless rim surrounding an area of small pores (e.g. in Eucampia); of dinoflagellates, a modified region of the chloroplast resembling a light-perceiving organelle, typically located in the left side of the cell.
(of diatoms, Family Thalassiosiraceae), a strutted process penetrating a diatom valve, but which also has a small covering, or operculum, occluding the satellite pores around the base of each process.
(of flagellates and ciliates), infraciliature located in or associated with the oral area.process. pl. otaria.
containing oxygen. cf. anoxic.
(of haptophytes, Order Prymnesiales), a stage during which flagella are discarded, and cells proliferate within a mucilaginous matrix. adj. palmelloid.
a small projection from the surface. adj. papillate.
(of coccolithophores), a heterococcolith with a rim in the form of a narrow, slightly flanged wall composed of elements of two alternating type, one relatively small and confined to the proximal part of the wall, and the other vertically expanded, e.g. in Papposphaera spp.
a cingular area in dinoflagellate cysts.
parietal :borne or located on the wall.
paroral :(of ciliates), at or along the right side of the buccal cavity. Also used as a noun for paroral membrane, i.e. a ciliary organelle lying along the right side of the buccal cavity.
pedicel :a type of holdfast organelle.
peduncle :a cytoplasmic appendage located near flagellar pores in some photosynthetic and non-photosynthetic dinoflagellates, associated with phagotrophy.
a rigid or semi-rigid investment of some dinoflagellates and all ciliates. adj. pellicular.
a type of ciliary membranelle positioned along the left wall in the buccal cavity of some oligohymenophorean ciliates. pl. peniculi.
referring to diatoms of the Order Pennales.
around the oral area.
(of ciliates), generally refers to the entire, expansive, "everted" oral area with its encircling adoral zone of membranelles, etc.
Subclass Peritrichia of Class Oligohymenophorea, a type of ciliate which, in the adult stage, has a characteristically inverted bell- or goblet-shaped or conical-cylindrical body, a conspicuous buccal ciliature at the apical pole, the somatic ciliature reduced to a subequatorial band and often a stalk (contractile or acontractile) or adhesive disc at the antapical pole; many species are sedentary (Order Sessilida) and form colonies.
the axis through the centre point of two valves.
resembling the petal of a flower.
ingestion of particulate food.
any heterotrophic organism that ingests or absorbs nutrients as solid particles from its surroundings. adj. phagotrophic.
(of ciliates), a tubular cytopharyngeal apparatus, often curved, with walls strengthened by longitudinally arranged nematodesmata. Depending on the origin of the microtubules, a cyrtos- or rhabdos -type can be distinguished.
a photosynthetic, flagellated organism.
that part of the plankton made up of autotrophic organisms.
plankton organisms in the size range 0.2-2 µm. adj. picoplanktonic.
coloured material in organisms, often associated with photosynthesis.
(of dinoflagellates), the active engulfing of small particles or liquids from prey cells.
(of coccolithophores), a heterococcolith composed of an upper and lower shield of radial elements, interconnected by a central column, e.g. in Calcidiscus leptoporus.
organisms drifting with the current, generally inhabiting the water column of an ocean, sea or lake; many planktonic organisms are capable of locomotion but are not sufficiently strong swimmers to move against the current. adj. planktonic.
(of diatoms), an element in the middle of the girdle when intercalary bands are present; any element in the absence of intercalary bands. pl. pleurae.
Deuxième Expédition Antarctique Française, 1908-10, commanded by Dr Jean Charcot, on board the Porquoi Pas?.
that part of the organism which proceeds last in forward movement.
(of dinoflagellates), a cingulum located below the midpoint of the cell.
parts per million.
a member of the Class Prasinophyceae.
(of dinoflagellates), a cingulum located above the midpoint of the cell.
(of diatoms, Family Rhizosoleniaceae), a permanent, elongate part of the valve with a truncate tip, considerably thicker than a flagellum (e.g. in Proboscia); the distal part fits into a groove on the adjacent valve of linked cells; of ciliates, Family Didiniidae, see oral cone.
lengthened, drawn out towards the poles.
protein silver impregnation of ciliates to stain the infraciliature (mainly kinetosomes, occasionally fibres), often nuclei and sometimes extrusomes, used to identify the ciliary structures.
a member of the Kingdom Protista.
members of the Phylum Protozoa, a term widely used to refer to heterotrophic flagellates, ciliates and amoebae.
(of diatoms), a solitary, marginal or submarginal structure evident as an open hole or an area covered by densely packed smaller areolae by LM. The principle diagnostic feature of Family Hemidiscaceae.
(of Class Heliozea), and also of amoebae, temporary extensions of the cell surface without defined shape, functioning in locomotion and/or food uptake.
(of tintinnid ciliates), lorica shape as in genus Ptychocylis.
dotted, marked with dots. n. puncta; pl. punctae.
a region of the chloroplast involved in starch formation in certain protists.
raphe :(of diatoms, Family Bacillariaceae), one or two longitudinal slits through the valve wall of raphid pennate diatoms possibly involved in the secretion of mucus for locomotion. cf. raphe sternum.
a network. adj. reticulate.
(of ciliates), a type of tubular cytopharyngeal apparatus; not curved, may be eversible, with walls strengthened by longitudinally arranged nematodesmata. Derived from circumoral kinetosomes and lined with extensions of transverse microtubules; often contains toxicysts.
having the shape of an oblique, equilateral parallelogram.
(of dinoflagellates, Family Protoperidiniaceae), supports for sulcal or cingular lists.
see labiate process.
(of diatoms), a solid disc attached by spokes to the surrounding silica framework of a velum. pl. rotae.
ribosomal RNA (ribonucleic acid), a nucleic acid within the cells of living organisms that is a vital component of protein synthesis.
an organism that feeds on soluble organic nutrients of dead or dying plants or animals. adj. saprobic.
a calcified or silicified, plate-like outgrowth.
(of ciliates, Subclass Scuticociliatia of Class Oligohymenophorea), usually a small, hook-like or whiplash group of often non-ciliferous kinetosomes posterior to the oral apparatus; during cell division, part of the new oral structures develops from this.
(of diatoms), a single element of the girdle.
scanning electron microscope/microscopy.
fixed to a substratum, e.g. by a stalk or lorica.
a hollow, bristle-like structure, often chitinous (in e.g. Chaetoceros). pl. setae.
Second International BIOMASS Experiment 1985, international research cruise on board R.V. Nella Dan, Indian Ocean sector of the Antarctic.
curved like the letter S.
of, relating to, or incorporating silica.
a member of the Class Dictyophyceae.
(of ciliates), the entire system of pellicular or cortical structures, organelles or markings that can be revealed by silver nitrate impregnation; often, however, referring only to the striated or reticulate system of 'lines' (fibres); structures are possibly involved in morphogenesis or conduction of stimuli.
relating to the body surface, or to non-reproductive structures or activities; in ciliates, relating to all parts of the body not associated with the oral structures.
spoon-shaped; broad at the tip and narrowed towards the base.
a solid protuberance or sharp, pointed structure, either part of a cell or secreted by it.
a small spine.
an isolated pore, typically in the central area of a valve face.
(of diatoms), surface ornamentation of areolae, pores of an alveolus appearing as lines or ridges. Orientation of striae is useful in identification, e.g. parallel, radiating, linear or convergent. pl. striae; adj. striate.
(of diatoms, Family Thalassiosiraceae), a tubular process penetrating a diatom valve, through which a thread of organic material (mostly chitin) is extruded. see trifultate, operculate strutted process; cf. occluded process.
(of ciliates, Class Phyllopharyngea), a conical, foot-like appendage projecting from the posterior ventral surface, through which a mucus-like filament can be secreted for temporary attachment to a substratum.
(of ciliates, Subclass Suctoria of Class Phyllopharyngea), a type of ciliate which, in the adult stage, is generally sedentary, lacks cilia, feeds by means of suctorial tentacles, and often has a non-contractile stalk; in the swarmer stage, is ciliferous and mobile.
(of dinoflagellates), a visible, linear boundary between thecal plates.
an organism living in a state of symbiosis with another, a relationship in which both partners benefit.
(of nassophorid ciliates), a hypostomial flange, perioral ciliature; a band of ciliature ('membrane') slightly posterior to oral area, ±traversing helically the ventral side and sometimes extending to the dorsal side, composed of closely set kinetal segments (mono-, di- or polykinetids).
the area of biology dealing with the classification, naming (nomenclature) and evolution of organisms.
transmission electron microscope/microscopy.
(of suctorians), a long, tubular cell projection, usually stiffened by microtubular bundles and equipped with haptocysts at the tip, extensible and retractable, used in prey capture and food uptake.
(of diatoms, Family Bacillariaceae), a thickening at the apical end of the raphe.
(of diatoms), a seta on the end valves of a chain.
Royal Society (London) Expedition Ship Terror, Antarctic expeditions of 1839-43, commanded by Francis Crozier.
a general term for a rigid shell or lorica around an organism. adj. testate.
plates of armoured dinoflagellates composed of cellulose or other polysaccharide microfibrils.
(of ciliates), adhering; also referring to specialised, somatic cilia that are modified to serve a tactile or adhering function.
a thin-layered plate within a chloroplast.
(of ciliates), a type of toxic extrusome, used in prey capture.
perpendicular to the transapical axis.
(of dinoflagellates and ciliates), an ejectile organelle.
radiating in three directions.
with three undulations or bulges.
(of foraminiferans), relating to chambers that are spirally coiled.
(of ciliates), an adult trophic and growing stage of the life cycle.
ending abruptly, as if cut off.
(of diatoms), a simple tube penetrating the valve wall.
(of diatoms), relating to the bottom of a substratum, e.g. ice, until detached into the surrounding water.
(of foraminiferans), having a small, central depression or hollow. adj. umbilicate.
(of dinoflagellates), cells without an identifiable theca or cell wall; while they do not have apical pore complexes, there may be an apical groove. Some species with thin thecal plates and apical grooves are considered to be transitional between unarmoured and armoured cells.
a plane of division parallel to the valve surface.
coccoliths on a coccosphere showing a continuous range of morphology between two end member morphologies, e.g. in Papposphaera borealis.
(of diatoms), a thin, perforated layer of silica across an areola; of dinoflagellates, a flat, cellular projection, especially in heterotrophic dinoflagellates, involved in locomotion and food uptake.
the underside of an organism; in dinoflagellates, the ventral side is identified by the presence of the sulcus; in ciliates, by the position of the cytostome, except when this is apical, then opposite to brosse (exception: suctorians); in testate amoebae, by the position of the pseudostome.
(of dinoflagellates), an identifiable ridge on the right side of the sulcal intrusion onto the epitheca.
with raised, worm-like markings, e.g. on the thecal plates of armoured dinoflagellates.
(of diatoms), cells joined in star-shaped colonies by mucilage pads (e.g. in Thalassionema).