Raphidocystis

Raphidocystis Penard, 1904 (ref. ID; 3691 original paper) or Penard emend. Nicholls & Durrschmidt (ref. ID; 4884)

Subclass Centrohelidia: Heliozoa (ref. ID; 7574)

Synonym Choanocystis Penard, 1904 (ref. ID; 3541)

[ref. ID; 1618]
Spicules of various forms. (ref. ID; 1618)

[ref. ID; 4884]
Emended diagnosis; Centrohelid heliozoa with the periplast comprising three types of scales: straight tubular or trumpet-like scales, smaller funnel-shaped scales, and elliptical or subrectangular plate-scales. Plate-scales have a conspicuously broad peripheral rim, an either smooth or patterned central area and a well-developed or vestigial median rim. Some remarks must be done about the type-species of Raphidocystis - R. lemani Penard. This species was described by Penard (1902) as lacking plate-scales in the periplast. However, there are not known acanthocystids of raphidiophryids lacking plate scales. Some specimens of R. lemani were observed by the author on the Kuybishev water reserve (central Russia). They have very few plate scales with reticulate surface similar to R. tubifera. We consider Penard did not observe its plate-scales because they are very few. (ref. ID; 4884)

  1. Raphidocystis glutinosa Penard, 1904 (ref. ID; 3541, 3691 original paper)
  2. Raphidocystis infestans Wetzel, 1925 (ref. ID; 1618)
  3. Raphidocystis lemani Penard, 1891 (ref. ID; 3541, 3691)
    Syn; Acanthocystis lemani Penard, 1891 (ref. ID; 3541) reported year? (ref. ID; 3691); Acanthocystis lemani var. plonensis Zacharias, 1894 (ref. ID; 3541) reported year? (ref. ID; 3691); Heterophrys pavesii Garbini, 1898 (ref. ID; 3541) reported year? (ref. ID; 3691); Raphidocystis lemani Penard, 1904 (ref. ID; 3541)
  4. Raphidocystis lepidula (Penard, 1904) Rainer, 1968 (ref. ID; 3541 redescribed paper)
    Syn; Choanocystis lepidula Penard, 1904 (ref. ID; 3541)
  5. Raphidocystis simplex (Schaudinn, 1897) (ref. ID; 3691) or 1898 (ref. ID; 3541)
    Syn; Acanthocystis simplex Schaudinn, 1898 (ref. ID; 3541) reported year? (ref. ID; 3691); Raphidocystis simplex Penard, 1904 (ref. ID; 3541)
  6. Raphidocystis stellata Penard, 1904 (ref. ID; 3541, 3691 original paper)
  7. Raphidocystis tubifera Penard, 1904 (ref. ID; 3541, 3691 original paper, 4710, 7574) reported year? (ref. ID; 1618, 4878)

Raphidocystis infestans Wetzel, 1925 (ref. ID; 1618)

Descriptions

Thin axopodia twice the body diameter; without radial spicules; feeds on ciliates. (ref. ID; 1618)

Measurements

Body 20-40 um in diameter. (ref. ID; 1618)

Raphidocystis tubifera Penard, 1904 (ref. ID; 3541, 3691 original paper, 4710, 7574) reported year? (ref. ID; 1618, 4878)

Descriptions

Spicules tubular with enlarged extremity; fresh water. (ref. ID; 1618)

[ref. ID; 7574]

Remarks

Previous descriptions of R. tubifera (Penard 1904; Rainer 1968) have included drawings based upon light microscopy only. Penard remarked that the S1 scales (-aiguilles tubulaires-) were difficult to discern except in dried preparations; with phase or interference contrast, however, they are visible on the cell in life. The S2 scales are not included in the type illustration (Penard 1904, p.194) although their presence is noted in the accompanying text. Rainer, on the other hand, depicts all the three scale types. Diameters of cells excluding the scale covering are given as 18 um (Penard) or 10-27 um (Rainer), which are in agreement with those of the present specimens. Penard describes long (S1) scales 13 um in length and oval (S3) scales 7x3 um; Rainer describes oval scales 6-8x3-4 um and depicts S1 scales up to 18 um long. Our S1 scales are thus somewhat longer than those previously reported. (ref. ID; 7574)

Examined material

Samples of surface water which yielded material of R. tubifera were collected by A.J.J.R. and G.F.L. from Sawley Dene, North Yorkshire, England (Grid Ref. SE 263667) in August and October 1976 and October 1977, at temperatures of 12-20 degrees C and pH 7.9-8.2, and by D.A.D. from Callanan Lake, Cariboo District, British Columbia, Canada (lat. 52 degrees 07'N, long. 122 degrees 35'W) in July and October 1978, at temperatures of 18.8-19.6 degrees C and pH 8.35-8.80. (ref. ID; 7574)

Measurements

Diameter about 18 um; envelope 25 um. (ref. ID; 1618)