Dendrobium speciosum (Dendrocoryne : Orchidaceae) complex in north Queensland

Abstract

Dendrobium speciosum Sm. has received insufficient taxonomic study north of St Lawrence, Queensland, where plants display much morphological variation in diverse habitats. Two varieties have been described previously, variety pedunculatum, occurring north of Townsville, and variety curvicaule for plants between the Connors Range south of Mackay and Annan River, south of Cooktown. In this multivariate analysis of 107 representative plants sampled from areas between St Lawrence and Cooktown, cluster analysis and principal coordinates analysis, were used to categorise the variation. Three overlapping varieties are revealed. North of Townsville variety pedunculatum intergrades with a medium-to-t..