PSALTERIOMONAS-LANTERNA GEN-NOV, SP-NOV, A FREE-LIVING AMEBOFLAGELLATE ISOLATED FROM FRESH-WATER ANAEROBIC SEDIMENTS

A novel amoeboflagellate, isolated from anoxic sediment samples, is described and named Psalteriomonas lanterna gen. nov., sp. nov. The cells of the flagellate stage show a fourfold rotational symmetry with four nuclei, four ventral grooves and four mastigont systems. Each mastigont has four flagella of equal length. Microtubular roots, striated roots or rhizoplasts and electron-dense structures are associated with their basal bodies. A Golgi apparatus is absent. Organelles surrounded by rough endoplasmic reticulum (RER) are presumably modified mitochondria. Methanogenic endosymbiotic bacteria are closely associated with microbodies and form a central body. Nuclear division shows the characteristics of a closed mitosis. Cells of the amoeboid stage are mononucleated and lack the methanogenic endosymbionts. Reproduction occurs in both stages of the life cycle. © 1990, Gustav Fischer Verlag · Stuttgart · New York. All rights reserved.