We investigate the diatom flora of Yamamuro Moor, a small intermediate moor formed in a valley bottom in the northeast of Lake Biwa in Shiga Prefecture, central Japan. It is a true Sphagnum moor with a thin peat bed despite its situation in the warm-temperate zone. A field survey and sampling took place on 21 April 2007. The water was slightly acidic (pH 5.3–5.8) with low electrical conductivity (2.8–3.4 mS m-1). From 24 diatom samples collected from the surfaces of spermatophytes, Sphagnum spp., and peat in the moor, 65 diatom taxa belonging to 22 genera were found. These are all listed and illustrated here, although six of them have not been identified to species. In terms of taxa richness, the dominant genus was Eunotia, represented by 16 taxa, followed by Pinnularia, with eight taxa.
2016 The Japanese Society of Diatomology