2020 Volume 36 Pages 47-67
For the purpose of fossil freshwater diatom study, diatoms of the early Miocene Futoro Formation distributed in Setana Town, west coast of Oshima Peninsula, Hokkaido, Japan were investigated. All samples were abundant in centric diatoms (80–92%), but many pennate diatom taxa were also found: 41 taxa of araphid diatoms in addition two taxa of genera and species indeterminable, 14 taxa of monoraphid diatoms and 74 taxa of biraphid diatoms, including some extinct species of all three. One Cocconeis taxon did not match any of the Cocconeis species reported to date. Unable to identify it, we propose it as a new species, Cocconeis setanensis Hidek.Suzuki sp. nov. Also, included herein are nomenclatural transfer for following three pennate taxa, Tetracyclus haradaae (Pantocsek) H.Tanaka, Geissleria longifissa (Hustedt) H.Tanaka and Sellaphora americana f. delicatula (Moisseeva) H.Tanaka, as well as information on 30, unique taxa found in the samples.
