Bicosoeca H. J. Clark 1866

Bicosoeca exilis Scale bar indicates 25 µm. Sample from the Lake Vollstedter See near Kiel, Germany. Sampling date 8/2018. The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Axioplan with Olympus OM-D M5 MKII. Image under Creative Commons License V 3.0 (CC BY-NC-SA). Place name: Lake Vollstedter See near Kiel (Germany) Latitude: 54.24105528 Longitude: 9.859339 Multiebenen-Abbildung, manuell gestapelt. Der Messbalken markiert eine Länge von 25 µm. Probe aus dem Vollstedter See bei Groß Vollstedt. Datum der Aufsammlung: 8/2018. Mikrotechnik: Zeiss Axioplan, Kamera: Olympus OM-D M5 MKII. Creative Commons License V 3.0 (CC BY-NC-SA). For permission to use of (high-resolution) images please contact postmaster@protisten.de.

Bicosoeca conica Scale bar indicates 25 µm. Sample from a tropical freshwater aquarium. The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Axioplan with Canon EOS 600D.Image under Creative Commons License V 3.0 (CC BY-NC-SA). Place name: Tropical freshwater aquarium Latitude: 54.3018013 Longitude: 10.07120132 Der Messbalken markiert eine Länge von 25 µm. Probe aus einem Süßwasseraquarium für tropische Fische. Mikrotechnik: Zeiss Axioplan Kamera: Canon EOS 600D. Creative Commons License V 3.0 (CC BY-NC-SA). For permission to use of (high-resolution) images please contact postmaster@protisten.de.

Bicosoeca lacustris Scale bar indicates 10 µm. Sample from a tropical freshwater aquarium. The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Axioplan with Canon EOS 600D.Image under Creative Commons License V 3.0 (CC BY-NC-SA). Place name: Tropical freshwater aquarium Latitude: 54.3018013 Longitude: 10.07120132 Der Messbalken markiert eine Länge von 10 µm. Probe aus einem Süßwasseraquarium für tropische Fische. Mikrotechnik: Zeiss Axioplan Kamera: Canon EOS 600D. Creative Commons License V 3.0 (CC BY-NC-SA). For permission to use of (high-resolution) images please contact postmaster@protisten.de.

San Martin De Castaneda, Castille and Leon, Spain

Bicosoeca conica Lemmermann, 1912. Bicosoeca cells with a body 2.5-5 microns in diameter, anterior flagellum 7-10 microns long, cell lives in a cone-shaped lorica with a stalk about 20 microns long that is slightly expanded at the point of attachment to the substrate.

Bicosoeca lacustris James-Clark, 1867. Bicosoeca cells measuring 4-7 x 2.5-4 microns The lorica is an elongate goblet-shape with a rounded posterior end and a rather thick pedicel terminating in a distal button. The margin of the lorica curves inwards slightly when the cell is in its extended shape, and closes partially or completely when the cell retracts. The anterior flagellum tends to be held out at an oblique angle, and the posterior flagellum either narrows at the distal tip or else is connected to the lorica by a fine filament.

Portrait of Bicosoeca petiolata, a colorless loricate flagellate (synonymous with Poteriodendron petiolatum). This species is colonial with daughter cells forming stalks attached to the mother lorica after division. Most species of this genus are solitary. The cells of this colony are retracted with the long hair bearing flagellum tightly coiled on the anterior end of the cell (seen well in the cell on your left in this image). The second short smooth flagellum is directed posteriorly attaching the cell to its lorica. The lorica is organic. From fresh water marsh with Typha (Cattail) near Boise, Idaho. Differential interference contrast.

Portrait of Bicosoeca petiolata, a colorless loricate flagellate (synonymous with Poteriodendron petiolatum). This species is colonial with daughter cells forming stalks attached to the mother lorica after division. Most species of this genus are solitary. The cells of this colony are retracted. The second short smooth flagellum is directed posteriorly attaching the cell to its lorica. The lorica is organic. From fresh water marsh with Typha (Cattail) near Boise, Idaho. Differential interference contrast.

Bicosoeca epiphytica Hilliard, 1971. Bicosoeca cells with a body 3.5-6.5 x 2.5-4.5 microns long, lorica 8-10x3.5-5 microns The lorica of this species has an undulating surface. The lorica has about 8-10 ridges and is rounded at the posterior. It tapers slightly at the anterior, before a flared aperture. The lorica has a short pedicel, which is 0.5-1 times the lorica length, and terminates with a distal button as is characteristic in this genus.

Bicosoeca gracilipes James-Clark, 1867. Bicosoeca cells with a body that is oval, 3.5-7 x 3-4.5 microns Cells may be nearly the same size as the lorica or else only half as long. Two flagella insert at the base of the cytostome. The posterior flagellum lies in a conspicuous longitudinal groove and attaches directly to the base of the lorica. The anterior flagellum varies between 2 and 5 times the cell length, and is held in almost the same axis as the cell, but is slightly curved. The lorica is thin-walled and has almost parallel sides, but is slightly pointed at the posterior. The anterior margin of the lorica is closely adpressed to extended cells and can only be seen when the cell retracts. It usually curves outwards slightly, but may also be straight, or curve inwards slightly. The lorica has a fine pedicel of 2.5-4.5 times the cell length. The nucleus is posterior.

Bicosoeca maris Picken, 1941. Bicosoeca cells measuring 4.5-6.5 microns, D-shaped with an inconspicuous lip anteriorly. Anterior flagellum about 2-2.5 times cell length, held in a loose coil when cells are retracted to the posterior of the lorica. Posterior flagellum lies in a shallow longitudinal groove, which passes down the cell and attaches to the base of the lorica. The lorica has parallel sides, with a rounded posterior and a slightly everted anterior margin. It measures about 10 microns in length and is about half as wide.

Bicosoeca planctonica Kisselew 1931. Bicosoeca cells with lorica measuring 10-15 x 10-15 microns (11-15x13-17 microns), cell diameter about 5 microns Lorica shaped like a bowl with rounded bottom and wide anterior opening with more or less incurved margin. The protoplast is rounded or slightly triangular in outline.

Bicosoeca pocillum Kent, 1880. Bicosoeca cells in which the lorica is cup-shaped or subcylindrical, rounded posteriorly, the anterior margin abruptly truncate, neither everted or constricted, varying in height from one and a half to two or three times its greatest breadth, pedicel short, rarely half as high as the lorica, cell is rounded posteriorly, the anterior margin flattened, with on one side as a broad, flattened, lip-like process, occupying from one third to one half of the cavity of the lorica, posterior retractile ligament equalling the body in length, contractile vacuole posteriorly situated, nucleus spherical, subcentral. Length of lorica 10.2 to 17 microns, cell 7.8 microns

Bicosoeca pulchra Hilliard, 1971. Bicosoeca cells with a lorica that is 19.3-20.2 microns long, 9.7-10.6 microns wide. The lorica is delicately urn-shaped, posteriorly pointed, with a short strip appended to the base. There is a slight constriction just below a moderately flaring opening, while the lip at the oral rim may converge slightly. The lorica wall is thin, hyaline, and appears serrate in optical profile when observed in aqueous methylene blue. Staining reveals the presence of transverse bands, which number 10-12 in 10 microns The spherical protoplast (6.5-7 microns long, 4.5-6 microns wide) is colourless, granular, and has a central nucleus and a vacuole. A single flagellum bearing two rows of submicroscopic hairs extends dorsally from the cell and is about three times its length.

Bicosoeca tenuis Kent, 1880. Bicosoeca cells with a lorica that is elongate-ovate or subfusiforme, nearly three times as long as broad, tapering equally at each extremity, pedicel scarcely one-half the height of the lorica, protoplast with a lip-like projection, slightly exsert anteriorly. Length of lorica 8.5 to 10.2 microns The assignment of this species to Bicosoeca is incorrect, because in Bicosoeca, one flagellum attaches the cell to the lower end of the lorica, whereas here both flagella project from the opening of the lorica.

Bicosoeca vacillans Stole, 1888. Bicosoeca cells located in a stalked lorica, the chamber of which measured 17-25 microns long. The lorica chamber was approximately cylindrical with a slightly pointed posterior and a pedicel of 1-1.5 times the lorica length. Loricas may differ slightly in shape. The lorica wall was most frequently curved slightly outwards at the aperture to a greater or lesser extent and in some cases the lorica was waisted below the aperture. The lorica had fine horizontal bands spaced about 0.4 microns apart, with numerous fine perpendicular fibres in each band. Cells were sub-spherical and had a flattened indistinct peristome. The anterior flagellum was about 3 times the cell length and held at an angle to the longitudinal axis of the cell. The posterior flagellum was attached to the base of the lorica via a fine thread.

The coiling of the long anterior flagellum when it retracts (seen in the lowermost cell here) is typical of this genus. There is a daughter cell adherent to the inner surface of the chitinous lorica by its posterior flagellum in this image. DIC.