A rediscovered rarity: Pimelea cruciata (Thymelaeaceae), a new species from Western Australia’s Mallee bioregion

More than 30 years ago, Eileen Croxford―a prolific plant collector, particularly in southern Western Australia―made three collections of an undescribed species of Pimelea Banks & Sol. ex Gaertn. from the Tarin Rock area. These specimens do not appear to have been incorporated into the collection at the Western Australian Herbarium (PERTH) until after revisionary work on the genus had been completed (Rye 1988). Although the new taxon has been informally recognised as P. sp. Tarin Rock (E.J. Croxford 2118) since 1999 (Western Australian Herbarium 1998–), its taxonomic resolution has been impeded by the paucity of herbarium material available for study combined with a lack of field observations. Targeted field research conducted in 2017 led to its rediscovery in the wild and confirmation of its status as a distinct species. Its description below adds to the spate of recent research on Pimelea that has included the recognition of eight new species from Queensland (Bean 2017) and one from Tasmania (Gray & Baker 2016), and resulted in an improved understanding of systematic relationships (Motsi et al. 2010; Foster et al. 2016).