Microworld

world of amoeboid organisms

Menu

Actinosphaeridium

A. pedatus, drawing after Penard, 1903

Genus Actinosphaeridium Zacharias, 1893

Actinosphaeridium pedatus Zacharias, 1893
Syn.: Nucearia caulescens Penard, 1903

Diagnosis: Cell surrounded by a mucous layer. Filopodia with granules, sometimes branching. Cell stalked; stalk ends at the cell body. During cyst formation the cyst is covered with siliceous plates.

Dimensions: Cell body 16-20 µm, with mucous layer about 40 µm.

Ecology: Several specimens between wet moss in a small pond on an ecoduct near Crailoo, the Netherlands, February 2021, just one week after the ice had melted.

Remarks: I could not detect any mucous layer in my specimens. It was not visible in phase contrast, nor in DIC. The cells were surrounded by a thin membranous shell, which was hard to detect.

Actinosphaeridium

Actinosphaeridium pedatus
Actinosphaeridium
Habitus, branched pseudopodium
Actinosphaeridium
Cell with captured prey
Actinosphaeridium
Actinosphaeridium
“Foot” of the stalk, attached to the cover glass
Actinosphaeridium
Phase contrast
Recent posts

Haplomyxa spec.

Main cell body Haplomyxa spec. Description: The cell had a cylindrical flattened body from which numerous granuloreticulopodia emerged. The common shape was more or less

Read More »

Valkanovia delicatula

V. delicatula, after Valkanov, 1962 Genus Valkanovia  Tappan, 1966 Diagnosis: Shell ovoid, oblate, elliptical in cross-section, composed of elongated elliptical hyaline scales arranged in a

Read More »

Gocevia pontica

Gocevia pontica, after Valkanov, 1934 Gocevia pontica Valkanov, 1934 Diagnosis: Clearly addressed bipolarity. Body covered by a weakly flexible tectum covered with foreign bodies. The

Read More »

Nabranella

N. brevis, after Snegovaya and Alekperov, 2009 Genus Nabranella Snegovaya and Alekperov, 2009 Diagnosis: Shell oval or spherical shape without neck. Apical top flat and

Read More »

Armipyxis

Genus Armipyxis Dekhtiar, 2009 Genus Armipyxis was created by Dekhtiar (2009) to accommodate all species with internal struts. However, C. aculeata may also have struts, although

Read More »

Netzelia pseudolimnetica

N. pseudolimnetica, after Penard, 1902 Netzelia pseudolimnetica Ogden and Meisterfeld, 1989 Synonym Difflugia limnetica (Levander, 1900) Penard, 1902. D. limnetica – Pejler, 1962, Oikos, 12,

Read More »

Cylindrifflugia hiraethogii

C. hiraethogii, after Ogden. 1983 Cylindrifflugia hiraethogii (Ogden, 1983) González-Miguéns et al., 2022 Diagnosis: the shell is light yellow or transparent, thin pyriform with a distinct

Read More »

Cylindrifflugia bacillariarum

  C. bacillariarum, 103 – 114 µm – Fochteloërveen, Netherlands   Cylindrifflugia bacillariarum (Perty, 1849) n. comb. González-Miguéns et al., 2022 Diagnosis: shell transparent, colorless or

Read More »

Cylindrifflugia elegans

C. elegans, length 84-102 µm, Gaasterland Cylindrifflugia elegans (Penard, 1890) n. comb. González-Miguéns et al., 2022 Basionym: Difflugia elegans Penard, 1890 Diagnosis: shell outline rough, pyriform

Read More »

Cylindrifflugia lanceolata

C. lanceolata, shells 153-169 µm long, nuclei 23-26 µm (Naardermeer, Netherlands) Cylindrifflugia lanceolata (Penard, 1890) n. comb. González-Miguéns et al., 2022 Basionym: Difflugia lanceolata Penard,

Read More »