Data on the geographical distribution of 36 species from 7 genera of the family
Volvocaceae sensu Nozaki (Pandorina, Volvulina, Yamagishiella, Eudorina,
Platydorina, Pleodorina and Volvox) have been summarized. Both cosmopolitan
species and species with local distribution have been detected. An attempt was
made to trace a correlation of latitudinal distribution of the coenobial volvocine
algae with obligatory differentiated somatic cells (22 species of the genera Volvox
and Pleodorina) with peculiarities of proceeding of the cell divisions during
asexual developmental cycle. In high latitudes of the Northern Hemisphere
(northward of 50-57° north) only 3 species of Volvox occur, in which the formation
of new coenobia (a series of consecutive gonidial divisions) starts with the light
period (in the morning), the rate of division is slow and the gonidial divisions are
temporarily blocked in darkness.
Key words: Volvocaceae, geographical distribution, developmental cycles.