Coccomyxa greatwallensis sp nov (Trebouxiophyceae, Chlorophyta), a lichen epiphytic alga from Fildes Peninsula, Antarctica

A single-celled green alga Coccomyxa greatwallensis Shunan Cao & Qiming Zhou, sp. nov., isolated from a specimen of Antarctic lichen Psoroma hypnorum (Vahl) Gray, is described and illustrated based on a comprehensive investigation of morphology, ultrastructure, ecology and phylogeny. The cells of C. greatwallensis are ovoid to long ellipsoidal and measured 3-5 mu m x 6-12 mu m. The new species has distinct ITS rDNA and SSU rDNA sequences and differs from the phylogenetic closely related species C. antarctica, C. arvernensis and C. viridis in cell size, distribution and habitat.