Re-isolation and revaluation of boundaries of Thecamoeba terricola Greeff, 1886 (Amoebozoa, Discosea, Thecamoebida), with description of Thecamoeba vicaria n. sp.

We studied a large species of Thecamoeba found in a glass dish with soaked moss and obtained 18s rRNA gene sequence of this organism. Morphologically, the strain was most similar to T. terricola sensu Page, but had significant differences in cell size and nuclear morphology.

Thecamoeba vumurta n. sp. (Amoebozoa, Discosea, Thecamoebida) from freshwater pond sediment - a sibling species of T. striata (Penard, 1890) Schaeffer, 1926.

Until recently, it seemed that amoebae of the genus Thecamoeba could be reliably identified using light-microscopic characters. However, recent studies show the presence of sibling species in the genus Thecamoeba, which can only be reliably distinguished based on the molecular data. Here we describe a new freshwater species, Thecamoeba vumurta n.

New data on the fine structure of Deuteramoeba mycophaga CCAP 1586/1 (Amoebozoa, Tubulinea).

The genus Deuteramoeba is one of the six amoebae genera belonging to the best-known amoeba family - Amoebidae (Amoebozoa, Tubulinea), containing such a popular species as Amoeba proteus. However, members of other genera of the family Amoebidae are much less known, and most of the studies of their morphology and ultrastructure date back to the 1970s and 1980s. Since these "classical" species are believed to be "well studied", their morphology and fine structure rarely become a subject of re-investigation.

Polychaos centronucleolus n. sp. - a new terrestrial species of the genus Polychaos (Amoebozoa, Tubulinea) with nontypical nuclear structure.

A new species of the "proteus-type" naked amoebae (large cells with discrete tubular pseudopodia) was isolated from tree bark sample of a birch tree in the surrounding of Kislovodsk town, Russia and named Polychaos centronucleolus n. sp. (Amoebozoa, Tubulinea).

Thecamoeba foliovenanda n. sp. (Amoebozoa, Discosea, Thecamoebida) - One more case of sibling species among amoebae of the genus Thecamoeba.

Until recently it seemed that amoebae of the genus Thecamoeba can be reliably identified using light-microscopic characters, like the size and shape of the cell, a characteristic pattern of folds and ridges and structure of the nucleus. However, recent molecular studies show the presence of sibling species that can be reliably distinguished based on the gene sequence data only. Here we describe a new terrestrial species, Thecamoeba foliovenanda n.