Re-assessment of the type collections of Corallinalean genera (Corallinales, Rhodophyta) described by V. P. Maslov

From 1935 to 1962 Maslov published two monographs and several other papers on the taxonomy of fossil calcareous algae of diverse ages from the large geographical area of the former USSR. Among many other taxa, he described five new genera (Solenophyllum, Palaeophyllum, Mesolithon, Bicorium and Tomilithon, as a subgenus of Parachaetetes Deninger) which he attributed to the Corallinaceae, and the new genus Karpathia, which he included in the Squamariaceae. Type material of these taxa, except for Mesolithon, is housed in the Geological Institute of the Russian Academy of Sciences, Moscow. Re-examination of the genus types from a modern perspective of coralline algal taxonomy shows that Karpathia is a validly published genus of corallinaceans (subfamily Mastophoroideae) to which several Cenozoic fossil species can be assigned. In contrast, the holotype of P. elegans, the type species of Palaeophyllum, cannot be assigned to any subfamily within the Corallinaceae and its preserved features are inadequate for confidently delimiting a separate genus. Solenophyllum is a valid genus in which Palaeozoic representatives of Corallinales formerly attributed to Parachaetetes Deninger can be included. Tomilithon is considered a younger heterotypic synonym of Solenophyllum. The algal nature of the bioclasts in the type of Bicorium is uncertain