A morphometric analysis of Struthanthus phillyreoides and S. dichotrianthus (Loranthaceae) suggests these represent one single variable species1,2

Abstract

Abstract Struthanthus is a large and diverse genus in Loranthaceae in the New World Tropics. In Venezuela, there are six species in the pedunculate triads-sessile flowers group to which Struthanthus phillyreoides Eichler and Struthanthus dichotrianthus (Kunth) Blume belong. The identification of S. dichotrianthus and S. phillyreoides has frequently been confused as both have lanceolate leaves, with an acute apex and base and 2-radiate umbellate inflorescences. An assessment of herbarium specimens revealed considerable morphological variation within S. dichotrianthus and this variation overlapped with S. phillyreoides. To objectively evaluate the identity of both species, multivariate analyses were performed on a morphological data set of 28 characters based on 131 specimens, collected over a wide geographical range. These analyses did not separate the two species but separated the specimens into two groups based on sex alone. When male and female subsets and vegetative characters were analyzed separately,...