C. gibbosa, after Van Oye, 1949
Cyclopyxis gibbosa Van Oye, 1949 *)
Basionym: Cyclopyxis arcelloides var. gibbosa Van Oye, 1949
Diagnosis: The dimensions and domed shape of the shell separate this species from all those with which it has certain common characteristics. It most closely resembles C. eurystoma, but differs in size. The ventral side of the test never carries larger stones, as is usually the case for C. eurystoma.
Dimensions: According to Van Oye (1949): Shell diameter 32.5 µm; height 30 µm; pseudostome diameter 10 µm. My measurements: Diameter 30.6 µm; height 31.5 µm; pseudostome diameter 10.6 µm (n=1).
Ecology.. Form with an aquatic tendency.
Geographical distribution: Java, Indonesia.
C. gibbosa, fen, Mongolia, 2023
*) Cyclopyxis arcelloides var. gibbosa Van Oye, 1949 changed to Cyclopyxis gibbosa Van Oye, 1949.
No new name needs to be established in this case under the International Code of Zoological Nomenclature. Because the name was published before 1961 using the abbreviation var., it is deemed subspecific under Article 45.6.4, unless explicitly proposed as infrasubspecific. As a species-group name, it is simultaneously established at both species and subspecies rank under the Principle of Coordination (Art. 46.1), with the same author, date, and name-bearing type. Accordingly, when treated at species rank, the correct name is Cyclopyxis gibbosa Van Oye, 1949.