An awn typology for Australian native grasses (Poaceae)

摘要: Australia has a large diversity of native grasses. The diaspores many species possess awns that vary considerably in their number and shape. Some variations awn shape have been found to be effective at diaspore dispersal. Although morphological descriptions exist for most grass species, the extent variation is unknown. This makes it difficult determine evolutionary importance potential function various morphologies. aim this study was construct an typology based on collated from published flora databases will quantify type all Australia, inform relationships help clarify role differing morphologies We 42.1% 1000 Australian grasses with single were determined ‘significant’ awn. These could classified into one 20 types, common being (1) single, apical, geniculate (once-sharply bent) (93 species; 28 genera, especially Iseilema), (2) three, apically-attached, straight (59 mainly Aristida) (3) bigeniculate (twice-sharply (46 Austrostipa). Among grasses, slightly (though significantly) more C3 (49.2%) had than C4 (39.9%), although types both contained sharply bent (bigeniculate respectively). Our classification system improve our understanding amount enable further investigation important ecological fitness.