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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Placus

Placus Cohn, 1866 (ref. ID; 2013, 7521)

From Dr. Inaki

Class Kinetofragminophora: Subclass Gymnostomata: Order Prostomatida: Suborder Prorodontina: Family Prorodontidae (ref. ID; 2013)
Kinetofragminophora: Gymnostomata: Prostomatida (ref. ID; 7521)

Synonym Spathidiopis Fabre-Domergue (ref. ID; 1618), Spathidiopsis Fabre-Domergue, 1889 (ref. ID; 3540), Thoracophrya Kahl, 1926 (ref. ID; 1618, 2013, 3540)

[ref. ID; 2013]
Body outline shape oval, small (30-70 um long), slightly compressed. Pellicle with conspicuously spiral ridges with distinct spots in the furrows between the ridges. Oral aperture oval and apically located, cytopharynx supported by trichites. Somatic ciliature uniform, with cilia emerging from spiral meridians of paired kinetosomes. There is a fibril (shown in protargol preparations) on the left of each pair of kinetosomes. The dorsal 'brush' is composed of a double parallel row of kinetosomes which arises adjacent to the oral aperture and terminates almost halfway down the body at the site of a lateral invagination of unknown function. Macronucleus ovoid to elongate, centrally located. Contractile vacuole either posterior or posterio-lateral.
Quote; Colin R. Curds "British and other freshwater ciliated protozoa Part I Ciliophora: Kinetofragminophora" Cambridge University Press, 1982 (ref. ID; 2013)
  1. Placus buddenbrocki Sauerbrey, 1928 (ref. ID; 1619, 1620, 3540)
  2. Placus dogieli Burkovsky, 1970 (ref. ID; 1620, 2112 original paper)
  3. Placus livida (ref. ID; 1620)
    Syn; Thoracophrya luciae var. livida Wang & Nie, 1932 (ref. ID; 1620)
  4. Placus luciae Kahl, 1926 (ref. ID; 1619, 1629, 3540), 1930 (ref. ID; 4488) reported year? (ref. ID; 3690, 5462) or (Kahl, 1926) Kahl, 1930 (ref. ID; 4611)
    Syn; Thoracophrya luciae Kahl, 1926 (ref. ID; 4611)
  5. Placus marina (ref. ID; 4611)
  6. Placus ovum Kahl, 1926 (ref. ID; 1619, 2117, 3540) reported author and year? (ref. ID; 4611)
  7. Placus socialis Fabre-Domergue, 1889 (ref. ID; 1335, 1619, 3540, 7521) reported year? (ref. ID; 1618)
    Syn; Nassula microstoma Calkins, 1903(?) (ref. ID; 1619, 3540) or Cohn, 1866 (ref. ID; 1622); Placus striatus Gourret & Roeser, 1886(?) (ref. ID; 1619, 3540); Thoracophrya marina Kahl, 1927 (ref. ID; 1619, 3540)
  8. Placus striatus Cohn, 1866 (ref. ID; 1619, 2117, 3119, 3540) reported author and year? (ref. ID; 4611)
    Syn; Placus sulcatus Mansfeld, 1923 (ref. ID; 1619, 3540)
  9. Placus sulcatus Mansfeld, 1923
    See; Placus striatus Cohn, 1866 (ref. ID; 1619, 3540)

Placus socialis Fabre-Domergue, 1889 (ref. ID; 1335, 1619, 3540, 7521) reported year? (ref. ID; 1618)

Synonym

Nassula microstoma Calkins, 1903(?) (ref. ID; 1619, 3540) or Cohn, 1866 (ref. ID; 1622); Placus striatus Gourret & Roeser, 1886(?) (ref. ID; 1619, 3540); Thoracophrya marina Kahl, 1927 (ref. ID; 1619, 3540)

Descriptions

Salt water. (ref. ID; 1618)
The ultrastructural study. (ref. ID; 7521)

Measurements

40-50 by 28-32 um, about 22 um thick. (ref. ID; 1618)