In: Phyton, 50 Fasc. 1 (2010), S. 69-89 with 6 figures

Key words: Mulga, Acacia aneura, Acacia ayersiana, Acacia craspedocarpa, Acacia paraneura, Acacieae, Mimosaceae, Mimosoideae. – Anatomy, morphology, pods, taxonomy. – Flora of Western Australia.

Summary

Rutishauser R., Pfeifer E., Reid J. E. & Maslin B. R. 2010. Pod characters of the Mulga group (Acacia aneura and close relatives), an important arid zone species-complex from Australia. – Phyton (Horn, Austria) 50 (1): 69–89, with 6 figures.

Mulga (Acacia aneura F. Muell. ex Benth. and its close relatives) is a very diverse, taxonomically complex and important group of species that is wide-spread and common in many parts of the inland, arid Australia. This preliminary morpho-anatomical examination of Mulga pods is based on selection of taxa that represent the range of carpological and taxonomic variation within the group. Although Mulga pods are somewhat variable they are always laterally flattened structures that are relatively short and broad, normally thin-textured, reticulately veined and possess either a wing or rim along their ventral and dorsal sides. This contrasts with the presumed closest relatives of Mulga which have ± terete or quadrangular pods that are more elongate (i.e. have a greater length : width ratio) and which are never winged. From both a taxonomic and phylogenetic perspective the most important Mulga carpological character relates to structure of the pod margins, whether they are winged or rimmed (i.e. wingless). Although wings and rims normally look very dissimilar, anatomically these structures appear to be homologous. In an associated study these pod margin characters, in conjunction with attributes of the branchlet resin, are used to define three major taxonomic assemblages within Mulga, namely, the Green alliance (pods rimmed, resin translucent), the Grey-green alliance (pods winged, resin translucent) and the Blue alliance (pods winged, resin opaque).