world of amoeboid organisms

1Shell is distinctly compressed laterally2
Shell is not compressed or slightly compressed laterally7
2Oval apertureC. compressa angustioris
Circular aperture3
3Shell length 45–63 μmC. angustastoma
Shell length 32–45 μmC. paludosa
Shell is smaller than 25 μm4
4Shell width is higher than lengthC. compressa australis
Shell width is smaller than length5
5Shell lanceolateC. lanceolata
Shell pyriformC. brevicolla
Shell ovate6
6There is a thick organic lip around an apertureC. compressa
There is no lip around an apertureC. compressa ovata
7Shell surface crenulate8
Shell surface not crenulate10
8Shell shape ovoid9
Shell shape globose or subgloboseC. crenulata globosa
9Shell length < 20 μmC. crenulata
Shell length > 20 μmC. splendida
10Shell is pyriform with prominent neck; surface covered by rare sand grains11
Shell is ovoid or globular, without prominent neck13
11Shell surface covered by rare sand grains12
Shell surface smoothC. collum
12Shell length 16–26 μm; aperture 4–5 μm; neck length is 1/3 of shell lengthC. sacculus
Shell length 27–30 μm; aperture 10–13 μm; neck length 1/4 of shell lengthC. sacculus sakotschawi
13Lateral sides of the shell are conic (angular)C. angulata
Lateral sides of the shell are rounded14
14Aperture diameter is equal to shell width15
Aperture diameter is considerably smaller than shell width16
15Shell width is equal to shell lengthC. pusilla
Shell width is considerably smaller than shell lengthC. pusilla conica
16Shell length is higher than 40 μm27
Shell length is lower than 40 μm17
17Shell length 8–12 μm18
Shell length is higher20
18Shell length is higher than shell widthC. minuta
Shell length is considerably smaller than shell width19
19Shell surface is covered by scarce sand grainsC. patinata
Shell surface is smoothC. bassini
20Shell surface is covered by scarce sand grains25
Shell surface is smooth21
21Aperture large, its diameter is about 1/3–1/4 of maximal shell width23
Aperture small, its diameter is about 1/6–1/8 of maximal shell width22
22Aperture diameter 1.5–2.5 μmC. leachi
Aperture diameter 3.5–4.5 μmC. vulgaris
23Shell ovoid24
Shell pyriformC. crenulata glabra
24Shell colorlessC. oviformis
Shell yellowish-brown, ovalC. oviformis fusca
25Shell subspherical, width/length ratio is higher than 0.8C. horrida
Shell elongated, width/length ratio is lower than 0.726
26Shell length 24–27 μmC. voigti
Shell length 20–24 μmC. psammophila
Shell length 17–21 μmC. angusta
27Shell length 40 μm, broadest width at the middle of the shellC. apiculata
Shell length 55 μm, broadest width at the upper third of the shellC. valida
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