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Toyemia Minich, 1990, is a widespread member of late Permian freshwater fossil assemblages of European Russia. The scales and lepidotrichia hemisegments of this taxon show general resemblance to the palaeoniscoid-type ʻganoidʼ scales of most Palaeozoic actinopterygians, but differ from these in some morphological features. Architecture of the vascular system is more complex: part of the canals (the wider ones) are located within the bone layer, constituting a complicated three-dimensional pattern, while the thinner canals usually lie on the border of the bone and the dentine layers (with the canal lumen usually surrounded by dentine but positioned in the basalmost part of the odontode), forming a regular network, especially in the posterior and ventral part of a scale. Whereas in most basal actinopterygians, vascular canals only occur underneath the sculptural ridges of the free field, scales of Toyemia possess wide, sinuous canals underneath the depressed field, opening to its surface in large pores. These and further features of the squamation (vascular canals cased in concentric layers of bone reminiscent of osteons and surrounded by numerous osteocyte lacunae; the presence of true secondary osteons; the shape of articulating elements and the general scale outline; the ornamentation of the free field, mainly consisting of concentric rolls; etc.) are similar to representatives of the Triassic order Scanilepiformes, especially to the family Evenkiidae, suggesting that Toyemia should be placed within this family. An enigmatic 'circular structure' of interwoven collagen fibers, first observed in Toyemia scales, is reminiscent of polypterid elasmodine. In several aspects, scales of Toyemia appear to represent the ancestral condition of the polypteroid scale. [ABSTRACT FROM AUTHOR]