Reassessing the generic status of Petalolophus (Annonaceae): Evidence for the evolution of a distinct sapromyophilous lineage within Pseuduvaria

Abstract

The genus Petalolophus (Annonaceae) consists of only one species, P megalopus, which is characterised by the possession of elaborate perianth wings that extend abaxially from the midrib of the inner petals. Recently published molecular phylogenetic data suggest that Petalolophus is congeneric with Pseuduvaria. Morphological and anatomical characteristics of both genera are critically re-examined and shown to support this conclusion: Petalolophus shares numerous characteristics in common with Pseuduvaria (particularly species from New Guinea) and it is only the autapomorphic possession of extended perianth wings that currently distinguish Petalolaphus from Pseuduvaria. Petalolophus megalopus is accordingly formally transferred to Pseuduvaria. Field observations reveal that the flowers of Pseuduvaria megalopus are visited by flies; it is likely that pollination is sapromyophilous, and that the inner petal wings attract flies by mimicking carrion. © Copyright 2005 by the American Society of Plant Taxonomists.