Five new records of the scale-bearing chrysophytes Mallomonas multiunca, M. paxillata, M. portae-ferreae, M. prora and M. retifera are reported for the Czech Republic. M. multiunca was found in a mesotrophic oxbow lake of the river Vltava. M. paxillata, M. portae-ferreae and M. prora were found in a mesotrophic to eutrophic floodplain pool of the river Lužnice. M. retifera was recorded from alluvial pools associated with the Vltava and Lužnice rivers, respectively. Autecology and distribution of the species are discussed. Three of the species occur in temperate and subarctic regions, M. paxillata probably has a cosmopolitan distribution and M. portae-ferreae prefers warmer water, occurring most frequently in tropical to subtropical regions.
A new species of Mallomonas, M. kalinae, is described from a small peaty pool Ostrov in the Bohemian Switzerland National Park (northern Bohemia). The species is located in the section Papillosae and its morphological characteristics are closest to M. rasilis, M. calceolus, M. binocularis and M. paxillata. However, it can be distinguished from these species by differences in scale and bristle morphology. Itwas previously reported from different parts of theworld, but its taxonomic status remained unrecognized due to the lack of a detailed investigation of cultured material. The taxonomy and distribution of the species are discussed and compared with information in the literature.