A revision of the Drosera omissa/D-nitidula complex (Droseraceae) from south-west Western Australia

Abstract

The Drosera omissa/D. nitidula complex is revised. Drosera omissa is reinstated and found to be conspecific with D. ericksoniae, which is reduced to synonymy. The taxon corresponding to the type of D. nitidula is determined and D. allantostigma and D. leucostigma are elevated from subspecific to specific rank. Drosera patens (known previously as D. nitidula subsp. 'omissa' and D. nitidula 'var. ?') is described as a new species. All five species are compared morphologically, described and illustrated. Cytological investigation found all species to have chromosome numbers of n = 14 and 2n = 28, suggesting a base number of x = 7 for the complex.