New observations on chromosome number variation in Hibiscus trionum s.l. (Malvaceae) and their implications for systematics and conservation

Abstract

Chromosome numbers have been determined for plants of Hibiscus trionum L. s.l. from nine locations: two inNew Zealand, five in Australia, and two in Africa. Two different numbers were obtained, one diploid with 2n = 28 and the other tetraploid with 2n = 56. The diploids were found in New Zealand and coastal New South Wales, all the other populations were tetraploid. Based on these observations, and plant morphology, especially flower shape and pigmentation patterns, the recent (1988) conclusion that all New Zealand m orphs of H trionum are naturalised is challenged and the morphs present different conservation options. © 2008 Taylor & Francis Group, LLC.