We describe Chloroparva pannonica Somogyi, Felfoldi & Voros gen. et sp. nov., a new
trebouxiophycean picoplanktonic alga isolated from a turbid, shallow soda pan in Hungary.
The cells are spherical to oval, less than 2 mu m in diameter, with simple ultrastructure
typical to small green algae. Cells divide by autosporulation, forming two daughter
cells per autosporangium. Cell wall structure consists of an outer trilaminar layer,
an inner microfibrillar layer and an electron-transparent layer covering the plasma
membrane. The trilaminar layer of the mother cell wall often persists around the autospores.
Typical chlorophyte pigments have been found, including chlorophyll a and b and lutein
as the dominant carotenoid. The main fatty acid was oleic acid. The phylogenetic position
of the new chlorophyte confirms the proposal of a new genus within the Trebouxiophyceae.
Based on its 18S rRNA gene sequence, this isolate is distantly related to Nannochloris
eucaryotum UTEX 2502, Chlorella minutissima C-1.1.9 and C. minutissima SAG 1.80 (<=
97.6% 18S rRNA gene pairwise similarities).