Abstract

During a survey of freshwater diatoms from streams in the upper reaches of the Liujiang River, Guangxi Province, China, a new Cymbella species, Cymbella liujiangensis sp. nov. was recorded. A detailed morphological description of C. liujiangensis is presented, based on light and scanning electron microscopy. The main features of C. liujiangensis include strongly dorsiventral valves with slightly truncate and obtusely rounded ends and one very large, transaspically-elongated stigma positioned on the ventral side of the central nodule and adjacent to the middle ventral striae. The new species is compared with C. dorsenotata, C. aspera, C. peraspera, C. australica, C. praerupta, C. convexa, C. crassistigmata, C. graciliformis and C. simonsenii, all of which show similarities to Cymbella liujiangensis, but differ in details of size, valve shape, striae density, puncta density, and number of stigmata.