Conserving Acacia Mill. with a conserved type : what happened in Melbourne?

Abstract

We here document what happened in Melbourne, Australia, in July 2011, regarding the confirmation of the inclusion of Acacia Mill. with A. penninervis as its conserved type in the Vienna Code. The procedures followed by the Nomenclature Section of the XVIII International Botanical Congress (IBC) are outlined and briefly described as far as they pertain to Acacia. The 2005 outcome of the controversial proposal to retypify Acacia Mill. from an African to an Australian type was confirmed by the Nomenclature Section following the ratification of the 2006, Vienna, International Code of Botanical Nomenclature (ICBN or Code) including the entry for Acacia. This, and other, decisions of the Nomenclature Section were in turn ratified by the final closing plenary session of the IBC held on 30 July 2011. The now-effective Code (incidentally in the future the International Code of Nomen clature for algae, fungi, and plants) emanating from the XVI II mc, will therefore include Acacia, with a conserved type, in the Appendix dealing with "Nomina generica conservanda et rejicienda". If the traditional classification system is 'followed that applies the name Acacia in a broad sense to an assemblage of legume species comprising a number of subgenera, this decision holds no implications at generic rank. However, should the alternative classification which segregates a broadly defined Acacia into a number of genera be followed, then the name Acacia would apply in a strict sense to the mainly Australian wattles (formerly Acacia subg. Phyllodineae, now Acacia subg. Acacia).