world of amoeboid organisms

Menu
Gocevia obscura
Gocevia obscura
Gocevia obscura, 52 and 43 µm, the same specimen

Gocevia obscura (Penard, 1902)

Diagnosis: amoeba more or less spherical in shape, with a central granular hump, partly or completely surrounded by a distinct hyaline margin; surface with a heavy covering of refractive mineral grains, which individually are clear or yellowish but give the cuticle a blackish appearance; cuticle is in rest spherical or ovoid; hyaline zone often irregular in outline with conical or digiform subpseudopodia and trailing filaments; cells uninucleate. Cysts observed.

Dimensions: Penard (1902): 25-30 µm, active up to 50 µm; Hoogenraad & De Groot (1940): 67-100 µm; my measurements 43-66 µm.

Ecology: fresh water, in sediments of clear water. Spiegelplas, Kootwijk, The Netherlands, Weser, Germany. Not common, but probably easily overlooked in its resting form. The species easily multiplies in wet mounts kept in a humidity chamber.

Remarks: the dense layer of mineral grains is supposed to be a flexible protection for the amoeba. The membrane resembles at first sight the shell of a Pseudodifflugia species.
This amoeba was described by Penard (1902) as Cochliopodium obscurum and placed in the genus Gocevia by Valkanov (1932). The name Gocevia obscurum is not correct and should be replaced by Gocevia obscura (Hoogenraad & De Groot, 1940).

Gocevia obscura
Gocevia obscura
Gocevia obscura
Gocevia obscura
Gocevia obscura, 67 µm, the same specimen changing within a minute
Gocevia obscura
Gocevia obscura
Gocevia obscura
The same specimen with different plasma shapes
Gocevia obscura
Gocevia obscura
Cell 35 µm in diameter and 23 µm high (bar = 10 µm)
Gocevia obscura
Drawing by Penard, in Faune Rhizopodique du Bassin de Léman, 1902
Gocevia obscura
Gocevia obscura, 58 µm
Gocevia obscura
Gocevia obscura, 66 µm
Recent posts

Sphenoderia compressa

Sphenoderia compressa, after Badewitz, 2002 Sphenoderia compressa Badewitz, 2002 Diagnosis: Test ovoid, oval in cross section, hyaline, covered with relatively small, oval, rather irregularly arranged

Read More »

Tracheleuglypha elongata

T. elongata, A-C after Thomas and Gauthier-Lièvre, 1959; D after Van Oye, 1959 Tracheleuglypha elongata Van Oye, 1959 Diagnosis: Test similar to T. dentata, but

Read More »

Tracheleuglypha acolla

T. acolla, after Bonnet and Thomas, 1960 Tracheleuglypha acolla Bonnet and Thomas, 1955 Diagnosis: Test ovoid, non compressed, round in cross-section, with large oval overlapping

Read More »

Cyclopyxis kahli oblonga

C. kahli f. oblonga , after Tarnogradskii, 1959 Cyclopyxis kahli f. oblonga  (Tarnogradskii, 1959) Centropyxis kahli f. oblonga Tarnogradskii, 1959 Diagnosis:  Test with all the

Read More »

Cyclopyxis leclercqi

Cyclopyxis leclercqi – from Beyens and Chardez, 1986 Cyclopyxis leclercqi Beyens and Chardez, 1986 Diagnosis: Shell circular in apertural view, dorso-ventrally compressed with a swollen

Read More »

Haplomyxa saranae

Haplomyxa saranae Dellinger, 2014 Diagnosis: cell body from small rounded (0.1 mm) to large elongated shape (up to 3.5 x 0.3 mm), usually flat but

Read More »