world of amoeboid organisms

Choanocystis rhytidos
From Siemensma, 1991

Choanocystis rhytidos (Dürrschmidt, 1987) Siemensma, 1991

Diagnosis: Periplast, 35-40 µm in diameter (measurement based on whole mount), with two types of scales; details of protoplast unknown. Spine scales, 9-12 µm long, bipartite, consisting of shaft and base-plate. Shaft cylindrical, 0.19 µm in diameter, presumably solid and slightly tapering towards the distal end, abrupt apically ending with 2-4 marginal teeth. Base-plate heart-shaped, 1.3 µm in diameter, Plate scales, 3.8-4 x 2.2-2.6 µm, elliptical or pear-shaped, ornamented by radially-arranged, branched furrows of different length. The area of the axial thickening and a narrow submarginal strip are smooth.

Distribution: Chile, New Zealand.

Remarks: A. rhytidos is common in Chile and New Zealand. Apart from the type locality it was found in samples from a semi-swamp forest on the shores of the Rio Oscuro, 35 km south of Puerto Montt, Chile, in swamps near Maramaranui, swamps near Lake Whangape, swamps aside the Manganahoe Lagoon, North Island, New Zealand and on the South Island in a swamp in the Buller Gorge. Temperature ranges from 7 to 12 °C, pH from 5.2—7.4, and conductivity from 20—800 pS25.

Recent posts

Cyclopyxis magna

Cyclopyxis magna – from Stepanek, 1967 Cyclopyxis magna Stepanek, 1967 Diagnosis: Test relatively high, covered with large mineral grains. The edge of the pseudostome is

Read More »

Cyclopyxis marinus

Cyclopyxis marinus – from Decloitre, 1977 Cyclopyxis marinus Decloitre, 1977 Diagnosis: Compared to Cyclopyxis aplanata the pseudostome is very minimally invaginated. It is surrounded by

Read More »

Cyclopyxis triangularistoma

Cyclopyxis triangularistoma – from Decloitre, 1980 Cyclopyxis triangularistoma Decloitre, 1980 Diagnosis: Ventral side exclusively covered with very small mineral grains, giving it a pearled appearance.

Read More »

Cyclopyxis pirini

Cyclopyxis pirini – from Golemansky 1974 Cyclopyxis pirini Golemansky 1974 Diagnosis: Ventrally, the test is circular. Laterally, the test is low hemispherical with a more

Read More »

Cyclopyxis eurystoma alta

C. eurystoma f. alta, after Jung, 1942 Cyclopyxis eurystoma f. alta  Jung, 1942 Diagnosis:  Test and coverage as the type. However, the side profile is

Read More »