world of amoeboid organisms


Key to Euglypha species

1 Fundus with a tuft of spines (Fig. 1) 2
Fundus without spines or when present spines not in a tuft 4
2 Fundus with 1-2 spines, shell 100-140 µm (Fig. 1e) E. mucronata
Fundus with a tuft of 1-8 spines, shell < 80 µm 3
3 Shell with somewhat concave sides (Fig. 1a-c) E. cristata
Shell ovoid, slightly compressed (Fig. 1d) E. bryophila

Fig. 1: a-c E. cristata b var. major d E. bryophila e E. mucronata

4 Shell usually with spines 5
Shell without spines 10
5 Spines are elongated tapering body scales 6
Spines are not part of body scales 9
6 Spines much longer than the scales 7
Spines about as long as the scales 9
7 Shell more or less broad ovoid, almost spherical E. cabrolae
Shell elongated ovoid 8
8 Shell with few long spines near the aperture (Fig. 2a) E. brachiata
Shell with some long spines near the fundus (Fig. 2c) E. acanthophora
9 Mid-body region with some randomly distributed pointed body plates. E. dickensii
Fundus region with sharply pointed body plates E. penardi

Fig. 2: a E. brachiata b E. scutigera c E. acanthophora d-e E. tuberculata

10 Shell ovoid, in cross-section circular 11
Shell ovoid or pyriform, in cross-section more or less compressed 13
11 Shell small, < 30 µm E. laevis
Shell > 50 µm 12
12 Scales oval (Fig. 2e) E. tuberculata
Scales pointed, scutiform (Fig. 2b) E. scutigera
13 Shell ovoid, slightly compressed, without spines (Fig. 3e-f) E. rotunda
Shell oviform or pyroid, usually with spines 14
14 Spines long 15
Spines short 16
15 Spines like needles, limited to the edge of the shell E. filifera
Spines usually lanceolate, but not always clearly visible; spines limited to the edge and the posterior end of the shell. E. compressa

Fig. 3: ad E. strigosa c var. glabra ef E. rotunda


16 Spines usually numerous, distributed all over the shell surface; Apertural scales clearly larger than the shell scales, about twice as wide; aperture usually round or slightly oval E. ciliata
Spines usually short and numerous, distributed all over the shell surface; Apertural scales about the same size as the shell scales E. strigosa
Key based on Hoogenraad en de Groot, 1940, and Edward Mitchell, 2003
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