world of amoeboid organisms

Menu
Pterocystis plumosa
From Siemensma, 1991

Pterocystis plumosa (Dürrschmidt, 1987) Siemensma, 1991

Diagnosis: Periplast, 20-30 µm in diameter (measurement based on whole mount), with two types of scales; details of protoplast unknown. The spine scales are 7-12 µm long, of feather-like appearance. The shaft, 0.01 µm in diameter, is cylindrical, hollow, ending apically with a blunt or abruptly cut off apex. The lateral wings are continued along 2/3 of the shaft, reaching their maximum breadth in the lower half of the spine scale. From here towards the proximal end, they are closely anchylosed with the basal wing and after considerably narrowing, form a patternless hollow stalk. The basal part of the stalk is foot-shaped. The lateral wings are ornamented with thin, delicate ribs which run from the shaft to the outer margin transverselly or obliquely.

Plate scales, 3.0-3.7 x 1.9-2.1 µm, ovoid or elliptical or sometimes asymmetrical. They are thin with deeply concave middle parts, elevated submarginal parts and slightly inflexed margins with a narrow rim. The axial thickening is slightly shifted to the smaller end of the scale.

Remarks: P. plumosa is closely related to P. pulchra. The major distinctive char­acteristic is the long, wingless distal shaft part. Spine scales with similar foot-shaped bases are also found in one form of P. pulchra which might be intermediary between P. plumosa and genuine P. pulchra.

Distribution: Chile.

Recent posts

Cyclopyxis overview 2

C. impressa C. impressa C. stellata C. stellata C. crucistoma C. crucistoma C. crucigenia C. crucigenia C. grospietschi C. grospietschi C. triquestrus C. triquestrus C.

Read More »

Cyclopyxis profundistoma

Cyclopyxis profundistoma – from Kufferath, 1932 Cyclopyxis profundistoma Kufferath, 1932 Diagnosis: The yellowish grey colored test is made of coarser mineral particles, which are connected

Read More »

Cyclopyxis maynei

Cyclopyxis maynei – from Kufferath, 1932 Cyclopyxis maynei Kufferath, 1932 Diagnosis: Test cylindrical, characterized by the size of the aperture, which is 87-97 μm wide

Read More »

Cyclopyxis kahli obliqua

C. kahli var. obliqua , after Decloitre, 1978 Cyclopyxis kahli var. obliqua   Decloitre, 1978 Diagnosis:  Test with all the characteristics of the type species

Read More »