world of amoeboid organisms


Key to Euglypha species

1Fundus with a tuft of spines (Fig. 1)2
Fundus without spines or when present spines not in a tuft4
2Fundus with 1-2 spines, shell 100-140 µm (Fig. 1e)E. mucronata
Fundus with a tuft of 1-8 spines, shell < 80 µm3
3Shell 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

4Shell usually with spines5
Shell without spines10
5Spines are elongated tapering body scales6
Spines are not part of body scales9
6Spines much longer than the scales7
Spines about as long as the scales9
7Shell more or less broad ovoid, almost sphericalE. cabrolae
Shell elongated ovoid8
8Shell with few long spines near the aperture (Fig. 2a)E. brachiata
Shell with some long spines near the fundus (Fig. 2c)E. acanthophora
9Mid-body region with some randomly distributed pointed body plates.E. dickensii
Fundus region with sharply pointed body platesE. penardi

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

10Shell ovoid, in cross-section circular11
Shell ovoid or pyriform, in cross-section more or less compressed13
11Shell small, < 30 µmE. laevis
Shell > 50 µm12
12Scales oval (Fig. 2e)E. tuberculata
Scales pointed, scutiform (Fig. 2b)E. scutigera
13Shell ovoid, slightly compressed, without spines (Fig. 3e-f)E. rotunda
Shell oviform or pyroid, usually with spines14
14Spines long15
Spines short16
15Spines like needles, limited to the edge of the shellE. 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

16Spines 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 ovalE. ciliata
Spines usually short and numerous, distributed all over the shell surface; Apertural scales about the same size as the shell scalesE. strigosa
Key based on Hoogenraad en de Groot, 1940, and Edward Mitchell, 2003
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