'Phebalium verrucosum' (Rutaceae), new status for a taxon excluded from 'P. squamulosum' on morphological and phytochemical evidence

Abstract

'Phebalium squamulosum' Vent. subsp. 'verrucosum' Paul G.Wilson (Rutaceae) is excluded from 'P. squamulosum' and raised to the rank of species as 'P. verrucosum' (Paul G.Wilson) I.Telford & J.J.Bruhl based on morphological and essential oil data. The distribution of the species is mapped and its conservation status is revised. The genus 'Phebalium' Rudge (Rutaceae), widespread through southern and eastern Australia, contains 28 species (Wilson 1970, 2013; Kubitzki et al. 2011; Australian Plant Census 2007-). Several species show considerable morphological variation and several more species may require recognition. In particular, 'P. squamulosum' Vent. exhibits considerable polymorphism, with nine subspecies currently recognised by Wilson (2013) in the last major revision of the genus. One of these, 'P. squamulosum' subsp. 'verrucosum' Paul G.Wilson, then known from few collections, was thought to be narrowly endemic to the Macleay River gorge system (Weston and Harden 2002, 2012) with Wilson (2013) presenting a wider distribution, citing a collection from Gloucester Tops.