Senecio repangae (Asteraceae):: a new endemic species from the north-eastern North Island, New Zealand

A new species Senecio repangae is described from the north-eastern North Island, New Zealand, where it grows primarily on offshore islands. It has previously been included within the widespread New Zealand endemic Senecio lautus, from which it is distinguished by its much taller, sparingly branched habit, longer and narrower capitula, much shorter, widely and unevenly spaced, recurved, incised ray florets, and by its chromosome number (2n = 100). A new subspecies, S. repangae subsp. pokohinuensis, endemic to the remote Mokohinau Islands group is also recognised. This allopatric taxon is distinguished from S. repangae subsp. repangae by its sparsely hairy, glabrescent, glaucous, adaxial leaf surface, smaller involucral bracts. and evenly spaced, longer, ray florets which are never recurved. The distribution, ecology, cytology, reproductive biology, conservation, and relationships of both subspecies to other New Zealand Senecio species are assessed.