2026 Volume 101 Issue 3 Pages 145-149
The genus Tabularia currently comprises 20 accepted diatom species, among which T. sinensis was first described from Poyang Lake, China. In this study, we re-examined Japanese specimens of T. sinensis using scanning electron microscopy, focusing on the structure of the valvocopula. In our previous report, we described the valvocopula of T. sinensis as open at one end. However, the present observations confirmed that it is closed at both ends. This feature has not been reported in other Tabularia species and is considered characteristic of the genus Ulnaria. The previously observed open-ended structures were likely artifacts caused by sample preparation damage. Recent molecular phylogenetic studies suggest that some species currently placed in Tabularia may require taxonomic reassessment. Morphologically, T. sinensis exhibits intermediate features between Tabularia and Ulnaria, suggesting a complex taxonomic position. (Continued from J. Jap. Bot. 95: 291–296, 2020)
