We present light and scanning electron microscope observations on six new species and one
previously described endemic species of the diatom genus Gomphonema Ehrenb. from the Hawaiian
Islands. The species are quite diverse morphologically. Some of the species have similarities to
species previously described from other parts of the world, notably African, Indian and new world
taxa, while the features found in other species are either similar to 'classical' species or have not been
described previously in the genus. Based on morphology, these species do not appear to be closely
related to one another, and they are widely distributed throughout the islands, with no finer-scale
pattern of distribution evident. The genus Gomphonema is well represented in Hawaii, with species
found in many of the streams across the state.