Taxonomic revision of scale-bearing heliozoon-like amoebae (Pompholyxophryidae, Rotosphaerida)

A taxonomic revision of heliozoon-like filose amoebae assigned to the Rotos phaerida is provided. The presence of spicules is a facultative feature in some species. Twelve species with plate-scales ornamented by several holes are placed in Pinaclophora Greeff, 1869. Three species with a single centra l hole in plate-scales are retained in Rabdiophrys Rainer, 1968. Four speci es lacking apical holes at plate-scales are transferred to a new genus Rabd iaster with R. pertzovi (Mikrjukov, 1994) as the type-species. Minute hexag onal perforations in tangential periplast elements and the eccentric positi on of the nucleus is considered as main distinguishing features of the Pomp holyxophryidae including genera Pinaciophora, Rabdiophrys, Rabdiaster and P ompholyxophrys Archer, 1869. The morphology of the plate-scales is used as a taxonomic character of the generic rank. Lithocolla Schulze, 1873 and Bel onacystis Rainer, 1968 are treated as taxa of uncertain position. Elaeorhan is Greeff, 1873 is transferred to Nucleariidae; the new marine species E. t auryanini with centric diatoms in the cell envelope is described. The terms Cristidiscoidida Page, 1987 and Cristivesiculida Page, 1987 are regarded a s junior synonyms of Rotosphaerida Rainer, 1968 and Aconchulinida De Saedel eer, 1934 respectively; the use of the formers is incorrect. The family Nuc leariidae Cann et Page is transferred to the order Rotosphaerida uniting no w all disciriscitate filose amoebas. A key to 27 pompholyxophryid species i s adduced.