A NEW FLAGELLATE (PERCOLOMONAS LACUSTRIS SP N., EXCAVATA, PERCOLOZOA) FROM AN INLAND SALT LAKE (SOUTHEASTERN EUROPEAN RUSSIA)

摘要

The external morphology and internal ultrastructure of a new species of excavate flagellate, which inhabits salt lake Novoe (Orenburg oblast, Russia) are considered. A cell of the flagellate has four naked flagella (one long and three short) extending parallel to each other. The long and one short flagellum terminate with acroneme. Three microtubular bands reinforce the longitudinal ventral groove. The vesicular nucleus lies in the anterior part of the cell. The mitochondria have discoid cristae. A system of submembrane microtubules originates from the fibrils close to the kinetosome and extends to the posterior cell end. The small bulbous projection is seen on the posterior cell tip. Dictyosomes of the Golgi apparatus were not found. The life cycle contains spherical thick-walled cysts that have the single hole with plug. The external structure of a cell and cysts of the similar species, Percolomonas cosmopolitus, is compared to that in P. lacustris. The new species differs from the known ones by the posterior bulbous projection, hole and plug inside cyst, acroneme of one short flagellum, and by some other features.