Taxonomic revision of the Salwoods: <i>Acacia aulacocarpa</i> Cunn. ex Benth. and its allies (Leguminosae: Mimosoideae: section Juliflorae)

Abstract

A taxonomic revision of Acacia aulacocarpa Cunn. exBenth. and its seven close relatives is presented. These species comprise the A. aulacocarpa group in the Acacia Mill. section Juliflorae and occur naturally in eastern and northernAustralia, New Guinea and Wetar, eastern Indonesia. In the past, the name A. aulacocarpa has been widely misapplied. This speciesis relatively uncommon but has an extensive geographic range extending fromthe Atherton Tableland region in Queensland, south to northern New SouthWales. Acacia aulacocarpa var. fruticosa C.T.White is considered conspecific with A. aulacocarpa . The name A. lamprocarpa O.Schwarz is reinstated for a northernAustralian taxon that extends from western Queensland through NorthernTerritory to the Kimberley region of Western Australia. Five new taxa aredescribed from A. aulacocarpa sens. lat ., namely A. celsa Tindale (Queensland), A. disparrima subsp. disparrima M.W.McDonald &amp; Maslin (northern New South Wales and Queensland), A. disparrima subsp. calidestris M.W.McDonald &amp; Maslin (Queensland), A. midgleyi M.W.McDonald &amp; Maslin (Queensland) and A. peregrina M.W.McDonald &amp; Maslin (New Guinea).A full description is provided for A. crassicarpa Cunn.ex Benth. Mainly on the basis of their mode of pod dehiscence, two subgroupswithin the A. aulacocarpa group are defined: A. aulacocarpa , A. celsa and A. disparrima comprise the A. aulacocarpa subgroup and have pods that dehisce alongthe dorsal suture; and A. crassicarpa , A. lamprocarpa , A. midgleyi , A. peregrina and A. wetarensis comprise the A. crassicarpa subgroup and have pods thatdehisce along the ventral suture. All species in the group, including theIndonesian species A. wetarensis , are illustrated and akey to the taxa is provided. Acacia celsa , A. crassicarpa , A. peregrina and A. midgleyi have considerable potential for wood production in tropical plantation forestry.