DESCRIPTION OF THE LARGE MULTINUCLEATE LOBOSE AMEBA CHAOS-GLABRUM SP.N. (LOBOSEA, AMOEBIDAE), WITH NOTES ON THE DIAGNOSIS OF THE GENUS CHAOS

Large, free-living multinucleate lobose amoeba Chaos glabrum sp. n. wa s isolated from the freshwater lake of Valamo Archipelago (north-weste rn Russia, the Lake Ladoga). Locomotive morphology, nuclear structure and other features of the present species were characteristic for the genus Chaos excepting the fine organisation of the cell coat, which co nsists of two layers of amorphous glycocalyx and has no discrete filam ents. Mitochondrial heteromorphism was detected in this species. The j ustification of the diagnosis of the genus Chaos is proposed in this p aper, and the validity of the genus Parachaos, which also has no filam entous glycocalyx is confirmed.