Gomphonema Ehrenberg species from the Yuntai Mountains,Henan Province,China

We report on eight species of the freshwater diatom genus Gomphonema from aquatic habitats from the Yuntai Mountains of Henan Province,China.This work represents the first detailed descriptions of the freshwater diatoms from this centrally-located province in China.Of the eight taxa considered,five are new to science and another is given a"cf."designation.Four of the eight species are similar in morphological features to other,"classical"species,with external areolar occlusions forming C-shaped openings.Another species is astigmate,and has distinct siliceous papillae located marginally on the exterior of the valves;this morphology has not been recognized previously for the genus.Two of the species have internal areolar and stigma occlusions.The diversity of morphological types of species in Gomphonema may relate to the ecosystems,with more diverse ecosystems harboring greater diversity of these morphological groups of Gomphonema.