Microworld

world of amoeboid organisms

Menu
General morphology of Lacogromia cassipara. ah – hyaline peduncular sheath; p – peduncle; e – internal channel; g – granuloreticulopodia; n – nucleus; m – membrane; x – xenosomes; c – cap of adhering bunch of xenosomes.

Class Monothalamea Pawlowski et al. 2013

Diagnosis: Foraminifera with a single chamber (monothalamous) test with an organic or agglutinated wall.

Remarks: Monothalamid foraminifera are widely distributed in marine and brackish habitats. Some members of this class are found in freshwater, but are rare. The main reason is probably that light microscopically, these tests are difficult to detect between debris, despite their relatively large size (250 µm on average, but up to 1 mm). Usually, the amoebae extend their pseudopodial network up to several mm when kept in Petri dishes or in wet mounts in moist chambers. Then they can be easily detected with an inverted microscope, preferably with dark field illumination or phase contrast.

The following non-marine families are known both morphologically and genetically:

Lieberkuehniidae: Lieberkuehnia, Claparedellus
Edaphoallogromiidae: Edaphoallogromia
Velamentofexidae: Velamentofex
Lacogromiidae: Lacogromia
Limnogromiidae: Limnogromia
Reticulomyxidae: Reticulomyxa, Haplomyxa, Dracomyxa, Wobo

Lacogromia cassipara, morphotype B; a adult specimen; b young specimens, just 24 hours after schizogony – drawing and micrograph Ferry Siemensma (1982)
Lacogromia cassipara, four young specimens, just 24 hours after schizogony (Siemensma, 1982)
Recent posts

Centropyxis tropica

C. tropica, after Deflandre, 1929 Centropyxis tropica  Deflandre, 1929 Basionym: Centropyxis aculeata var. tropica Deflandre, 1929 Diagnosis: As for C. aculeata, but with much longer

Read More »

Centropyxis nauwercki

Centropyxis nauwercki, after Schönborn, 1975 Centropyxis nauwercki  Schönborn, 1975 Diagnosis: Shell divided by a ring groove into a highly convex, balloon-shaped fundus part and a

Read More »

Centropyxis pontifera

Centropyxis pontifera, after Bartos, 1963 Centropyxis pontifera  Bartos, 1963 Diagnosis: Test large, broadly oval, formed of a thick, solid, brownish-yellow organic matter. Test with many

Read More »

Centropyxis pyriformis

Centropyxis pyriformis, after Van Oye, 1958 Centropyxis pyriformis  Van Oye, 1958 Diagnosis: This species is distinguished from C. aculeata by its narrowed shape towards the

Read More »

Centropyxis dentistoma

Centropyxis dentistoma, after Decloitre, 1949 Centropyxis dentistoma  Decloitre, 1949 Basionym: Centropyxis aculeata var. dentistoma Decloitre, 1949 Diagnosis: Pseudostome lobed, with 4 to 7 sharp teeth,

Read More »

Centropyxis compressa

Centropyxis compressa, after Van Oye, 1948 Centropyxis compressa  Van Oye, 1948 Diagnosis: Test a little elongated and very flattened regularly, like that of Arcella discoides;

Read More »

Centropyxis lata

Centropyxis lata, after Jung, 1942 Centropyxis lata  Jung, 1942 Diagnosis: Shell coarse-scaled, covered with a mix of diatoms and detritus; pseudostome large, ventral side mostly

Read More »

Centropyxis aurita

Centropyxis aurita, after Laminger, 1973 Centropyxis aurita  Laminger, 1973 Diagnosis: In ventral view, the shell is more or less broadly ovoid in outline. Quite straight truncated

Read More »

Centropyxis grelli

Centropyxis grelli, after Laminger, 1973 Centropyxis grelli  Laminger, 1973 Diagnosis: Shell covered with relatively large mineral particles. The pseudostome outline is formed by two convex arches.

Read More »

Centropyxis adami

Centropyxis adami, after Laminger, 1971 Centropyxis adami  Laminger, 1971 Diagnosis: In ventral view, the outline of the shell is more or less elliptical, in side

Read More »