[TH] Two new taxa of Achnanthidium and Encyonema (Bacillariophyceae) from the Yom River, Thailand, with special reference to the areolae occlusions implying ontogenetic relationship
[EN] Two new taxa of Achnanthidium and Encyonema (Bacillariophyceae) from the Yom River, Thailand, with special reference to the areolae occlusions implying ontogenetic relationship