Centrohelid heliozoans are non-ciliated axopodial protists of uncertain affinities. Cell coverings (organic spicules, siliceous plate-scales and spine-scales) are the main criterion for species identification and higher-rank taxonomy in this group. Phylogenetic reconstructions of centrohelids evolution are mostly based on the sequences of 18S rRNA gene. Newly obtained 18S rRNA sequences, as well as light- and electron-microscopic data led to discoveries of some previously unknown evolutionary events in centrohelids. An interpretation of the cell coverings evolution as a mostly parallel process in two orders is proposed. According to this hypothesis cell coverings were ancestrally organic, then independently silicified and after that multiple cases of desilicification or even complete loss of coverings took place. The family Raphidiophryidae was shown to be polyphyletic and spread between two centrohelid orders. The organisms with organic spicules only (here referred to as Heterophrys-like organisms, HLO) reve