The Lehmannianae: a Natural Group of Western Australian Eucalypts

Abstract

A new series of Eucalyptus L'Hérit. is defined. It includes E. lehmannii (Schau.) Benth., E. burdettiana Blakely & Steedman and E. megacovnuta C. A. Gardn. In addition, four new species (E. conferruminata, E. bennettiae, E. newbeyi and E. talyuberlup) are described. A long-standing misapprehension concerning the identity of E. lehmanniiis removed. E. macvocera Turcz. (as to type) with which E. talyubevlup and other species have been identified is shown to be synonymous with E. cornuta Labill. Four of the species of the series are lignotuberous and are therefore actually or potentially mallees. The others are small trees. All have spirally arranged adult leaves in three orthostichies (phyllotaxis (3 + I)) and seedling leaves and stems with emergent oil glands ('stellate hairs') crowned with radiately arranged unicellular hairs. The stomata of adult leaves are arranged in chains in crypts. The pith of the stem lacks oil glands. The cotyledons are forked or bilobed. The basitonic inflorescences bear sessile or subsessile flowers with horn-shaped opercula on deflexed, flattened peduncles which have multiple vascular strands. The phyllotaxis of series Lehmannianae and the form of the nectary in E. bennettiae are unique among eucalypts. All the species of the Lehmannianae are endemic to the south coastal region of Western Australia.