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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Phryganella

Phryganella Penard, 1902 (ref. ID; 3693 original paper)

Rhizopoda: Testacea: Order Testacealobosa De Saedeleer, 1934: Reticulobosa: Family Phryganellidae Jung, 1942 (ref. ID; 7500)

Family Phryganellidae Jung (ref. ID; 7501)

ref. ID; 1618

Test spheroidal or ovoid, with sand-grains and minute diatom shells; aperture terminal, round; pseudopodia drawn out to a point; fresh water. (ref. ID; 1618)

ref. ID; 1923

Shell membranous, densely covered with sand grains or with diatoms or other foreign elements. (ref. ID; 1923)

ref. ID; 3686

Shell colourless, yellow or brown; hemispherical or ovoid; composed of agglutinated mineral particles; aperture terminal, circular. (ref. ID; 3686)
  1. Phryganella acropodia (Hertwig & Lesser) (ref. ID; 1618) or (Hertwig & Lesser, 1874) Hopinkson, 1909 (ref. ID; 661, 2054, 2083, 2099, 2109, 2110, 2142, 2189, 2349, 2456, 4737, 4755, 5461) reported year? (ref. ID; 3383) reported author and year? (ref. ID; 891, 6944)
    Syn; Phryganella hemisphaerica Penard (ref. ID; 891, 2142)
  2. Phryganella acropodia var. australica Playfair, 1917 (ref. ID; 2142)
  3. Phryganella acropodia var. depressa Playfair, 1917 (ref. ID; 2142)
  4. Phryganella acropodia var. penardi Decloitre, 1955 (ref. ID; 2054, 2142, 2144) reported year? (ref. ID; 3383)
  5. Phryganella acropodia var. penardi f. alta Schonborn, 1964 (ref. ID; 2142) reported year? (ref. ID; 3383)
  6. Phryganella dissimulatoris Chardez, 1969 (ref. ID; 2142 original paper)
  7. Phryganella hemisphaerica Penard (ref. ID; 1923, 2114, 2558, 2592, 3283, 3693, 7857)
    See; Difflugia acropodia Hertwig-Lesser (ref. ID; 2489), Phryganella acropodia (ref. ID; 2142)
    Syn; Pseudodifflugia hemisphaerica Penard (ref. ID; 3693)
  8. Phryganella marinus Chardez, 1971 (ref. ID; 2114, 2144 original paper, 3519)
  9. Phryganella microps Valkanov, 1963 (ref. ID; 2142, 4860)
  10. Phryganella nidulus Penard, 1902 (ref. ID; 3686, 3693 original paper, 7500) reported year? (ref. ID; 1923, 2142)
  11. Phryganella paradoxa Penard, 1902 (ref. ID; 2057, 2142, 2441, 3686, 3693 original paper, 5461)
  12. Phryganella paradoxa var. alta Bonnet & Thomas, 1960 (ref. ID; 2142, 2160, 2457, 2466 original paper)

Phryganella acropodia (Hertwig & Lesser) (ref. ID; 1618) or (Hertwig & Lesser, 1874) Hopinkson, 1909 (ref. ID; 661, 2054, 2083, 2099, 2109, 2110, 2142, 2189, 2349, 2456, 4737, 4755, 5461) reported year? (ref. ID; 3383) reported author and year? (ref. ID; 891, 6944)

Synonym

Phryganella hemisphaerica Penard (ref. ID; 891, 2142)

Descriptions

The shell of Phryganella acropodia, from light microscopic observations, is usually either light or dark brown in colour, with newly formed daughter shells being transparent or light yellow. Scanning micrographs show that it is approximately hemispherical in shape and semi-circular in lateral view, has a small slightly invaginated rim, and is composed mainly of small or medium sized mineral grains. These grains are incorporated into the matrix to give a regular, smooth, outline around the apertural and central regions but at the aboral extremity more angular grains may be incorporated. Organic cement is only occasionally visible as small strands between adjacent particles. The aperture is large, circular and clearly defined due to the wide border of smooth organic cement which surrounds it. Examination of portions from broken specimens reveal that organic cement lines the inner surface which is always smooth and featureless. However, the outer face of the wall is composed of a small open network into or onto which the mineral particles of the surface are either bound or embedded. At the aperture this inner network is curved over so that it becomes, for the extend of the organic border, the outer region with mineral particles sandwiched between layers of organic network. It is noticeable that in these agglutinate shells the apertural region is thickened by incorporation of mineral particles between building units, but at the fundus only a thin layer of units lines the inner surface onto which a thick layer of grains is attached. (ref. ID; 891)

Test circular in aperture view; hemispherical in profile; yellowish or brownish, semi-transparent, and covered with sand-grains and scales; in front view sharply pointed pseudopodia radiating; colorless endoplasm usually with chlorophyllous bodies. (ref. ID; 1618)

Shell hemispheric, yellowish-brown, composed of xenosomes. Separation from the very similar Cyclopyxis eurystoma by means of the non invaginated aperture. (ref. ID; 4755)

Comments

Initially it was described as a species of Difflugia by Hertwig & Lesser (1874) being transferred to the genus Phryganella by Penard (1902). Penard erected this genus to accommodate those hemispherical specimens of Difflugia which had pseudopodia that varied from broad lobate to narrow digitate with pointed extremities, and included, D. acropoida as a synonym of his P. hemispherica (Penard, 1890). Since then Cash & Hopkinson (1909) have corrected the designation of the species and it has become P. acropodia. As these latter authors of pointed out, 1 of the difficulties in identifying empty shells of P. acropodia is its similarity to empty shells of Difflugia globulus and Pseudodifflugia gracilis which all share roughly similar dimensions and shell architecture. The composition of the shell matrix in these species also varies, with soil specimens being predominantly composed of mineral grains, whereas those in Sphagnum and freshwater are composed mainly of siliceous shell plates and whole or broken portions of diatom frustules. (ref. ID; 891)

Measurements

30-50 µm in diameter. (ref. ID; 1618)

Phryganella hemisphaerica Penard (ref. ID; 1923, 2114, 2558, 2592, 3283, 3693)

See

Difflugia acropodia Hertwig-Lesser (ref. ID; 2489), Phryganella acropodia (ref. ID; 2142)

Synonym

Pseudodifflugia hemisphaerica Penard (ref. ID; 3693)

Descriptions

Small size (30-50 µm), foreign elements small (diatoms and sand grains). Shell hemispherical, yellowish or brownish in color. Aperture large without any invagination, sometimes bordered with greater scales or grains. Pseudopodia as in the preceding species. Habitat the ooze of ponds and lakes. (ref. ID; 1923)

Measurements

Diameter 40-55 µm. (ref. ID; 1923)

Phryganella microps Valkanov, 1963 (ref. ID; 2142, 4860)

Descriptions

A very small hemispherical shell, from bottom view circular, shell translucent, light brown, practically only of organic matter, covered with rare small mineral particles. Aperture large, circular. (ref. ID; 4860)

Measurements

Diameter of the shell 11-16(13.5+/-2.5), height of the shell 8-11(9.5+/-1.5), aperture of the shell 8-13(10.5+/-2.5) µm (n=5). (ref. ID; 4860)

Phryganella nidulus Penard, 1902 (ref. ID; 3686, 3693 original paper, 7500) reported year? (ref. ID; 1923, 2142)

Descriptions

Large size (165-220 µm), foreign elements large. Shell hemispherical, usually of rough contour. Aperture large. Pseudopods slender, but often accompanied by broad lobes of protoplasm extending radially in all directions. Animal very shy; without an examination of the living organism, the identification of the shell alone is not possible. Habitat the ooze of ponds and lakes. (ref. ID; 1923)

The shell is opaque, large, circular and hemispherical in lateral view. It is composed of a mixture of quartz particles and diatom frustules, the distribution of a few large particles in this mixture contributes to the irregular outline of the shell and aperture. The aperture is concentric and slightly invaginated. (ref. ID; 3686)

Measurements

Diameter 180-200 µm. (ref. ID; 1923)

Diameter of shell 171-356; depth of shell 89-157; diameter of aperture 93-187 µm (n=5). (ref. ID; 3686)

Phryganella paradoxa Penard, 1902 (ref. ID; 2057, 2142, 2441, 3686, 3693 original paper, 5461)

Descriptions

The shell is colourless or yellow, ovoid and circular in transverse section. The walls are thin and composed of small siliceous plates and some pieces of diatom frustules. The aperture is usually circular, but because of the thin walls it may sometimes be distorted. (ref. ID; 3686)

Measurements

Length of shell 37; breadth of shell 31; diameter of aperture 15 µm (n=1). (ref. ID; 3686)