world of amoeboid organisms

Menu
Rabdiophrys anulifera
Rabdiophrys anulifera

Rabdiophrys anulifera Rainer, 1968, emend. Siemensma, 1981

Diagnosis: Cells 27-35 µm in diameter, covered with plate- and spine-scales. The species resembles much R. monopora, and differs from it in having small (1.2-3.4 µm) as well as long spine-scales (10-12.2 µm) and an aberrant ultrastructure of the plate-scales. Both species have plate-scales consisting of 2 layers fused peripherally and in the case of R. anulifera by 2 concentric internal rims, one lying halfway between the periphery and the central hole and the other rim just around the border of the central hole. These rims can sometimes be seen by SEM. In R. monopora the 2 layers of the plate-scales are also fused peripherally, but they are interconnected by material which appears in places as black dots, as could be seen by TEM. The diameter of the plate-scales of R. anulifera is 2.1-2.8 µm with the central hole ca. 0.8 µm in diameter. The spine-scales are distally strongly flattened and somewhat broadened, ornamented with 2 small and pointed teeth. The shaft is 0.24-0.50 µm in diameter; the apex is ca. 0.7 µm broad. Proximally the shaft is connected to a circular base plate, 0.57-1.2 µm in diameter, by four wing-like structures.

Remarks: This species was studied with transmission electron microscopy by Nicholls (1983) and described as P. pinea, now a junior synonym of R. anulifera. This species has been reported from Germany (Rainer 1968), The Netherlands (Siemensma 1981) and Canada (Nicholls 1983), all from freshwater localities. I found this species again in 2011, 2015 and 2019 at several locations in the Netherlands.

Rabdiophrys anulifera
Rabdiophrys anulifera, Gaasterland 2019
Rabdiophrys anulifera
Rabdiophrys anulifera, from Siemensma, 1981
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera, Laegieskamp
Rabdiophrys anulifera
Rabdiophrys anulifera
Rabdiophrys anulifera
Recent posts

Quadrulella scutellata

Quadrulella scutellata, after Wailes, 1912 Quadrulella scutellata  Wailes, 1912 Diagnosis: Test moderately large, hyaline, pyriform, compressed; composed of small siliceous, rectangular plates arranged in irregular

Read More »

Mrabella plicata

M. plicata, after Hoogenraad and De Groot, 1940 Mrabella plicata (Hoogenraad and De Groot, 1940) Diagnosis: Test made of small square plates, between which some

Read More »

Quadrulella alata

Q. alata, after Gauthier-Lièvre, 1957 Quadrulella alata  Gauthier-Lièvre, 1957 Diagnosis: In frontal view, the test is lageniform, with a broadly rounded fundus (subcircular or ovoid)

Read More »

Quadrulella acuminata

Quadrulella acuminata, after Van Oye, 1958 Quadrulella acuminata  Van Oye, 1958 Diagnosis: Test rather pyriform with a stretched base with converging sides, very slightly concave

Read More »