world of amoeboid organisms

Menu
Choanocystis lepidula

Choanocystis lepidula (Penard, 1904) Siemensma & Roijackers, 1988

Diagnosis: Cell diameter 10-18 µm, periplast up to 23 µm; spine scales 7.1-9.5 µm long; shaft cylindrical, 0.22 µm thick and with an abruptly cut off apex; shaft curved proximally and seated at the apex of an invagination of the basal plate; basal plate 1.7-1.8 µm in diameter and surrounded by an upwardly bent rim, ca. 0.1 µm thick; basal plate extends for a short distance along the shaft; plate scales 4.2-5.2 x 2.3 µm, ovoid to oblong, with a central depression, ornamented with irregularly distributed granules and with a narrow longitudinal rib.

Remarks: I have seen many proximally curved spine scales, but also many more or less straight shafts were observed. Therefore, it is likely that not all specimens have the typical habitat as shown by Penard’s (1904) single figure. Two related species are Choanocystis perpusilla and C. rotundata. The first differs from C. lepidula in having two teeth on its apex. The plate-scales of C. rotundata are smooth, whereas those of C. lepidula have a longitudinal rib.

Choanocystis lepidula
Choanocystis lepidula, with the typical proximally curved spine-scales arranged around the axopodia – Laegieskamp.
Choanocystis lepidula
Choanocystis cf. lepidula
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 »