Abstract
A culture belonging to the Mallomonas favosa morphotype from Vietnam has been studied. The ultrastructure of the scales and bristles was revealed using transmission and scanning electron microscopy. Comparison of cultures from Vietnam and Europe, morphologically similar to Mallomonas favosa, using SSU rDNA + rbcL cpDNA and ITS rDNA datasets showed that the tropical culture forms a separate phylogenetic lineage. Based on these data, a new cryptic species, Mallomonas neofavosa sp. nov., is described.
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