Observations on the genus Elymus (Poaceae : Triticeae) in Australia

In Australia, the genus Elymus L., as currently interpreted, includes two s pecies: E. scaber (R.Br.) A.Love [with two varieties E. scaber var. scaber and E. scaber var. plurinervis (Vickery) B.K.Simon]; and E. multiflorus (Ho ok.f.) Love & Connor. A third species, apomictic E. rectisetus (Nees) A.Lov e & Connor, which is naturalised in New Zealand from Australia has not been included in Australian regional Floras except as a synonym of E. scaber. A preliminary phenetic analysis of morphological characters of 19 specimens and reports on recent work indicate that at least four major entities exist : short-awned entities (E. scaber sensu Labillardiere); long-awned apomicti c entities (sensu E. rectisetus); long-awned entities with large glumes (E. scaber var. plurinervis); and very short-awned entities (E. multiflorus). In a study of seed set, long-awned entities of E. scaber exhibited relative ly low seed set (12-26%), a reported feature of E. rectisetus. The results, taxonomy, and recent studies of the reproductive biology, geographic distr ibution and genome constitution of taxa of Elymus common to Australia and N ew Zealand are discussed, and a revision of the current taxonomic ranking i s suggested.