Morphological studies of the pea tribe Bossiaeeae

Project summary

Bossiaeeae is a tribe in the pea family (Fabaceae) endemic to Australia. It currently comprises six genera: Bossiaea, Platylobium, Goodia, Muelleranthus, Ptychosema and Aenictophyton. The tribe contains herbaceous perennials, subshrubs and shrubs and has a widespread distribution, mostly in temperate and subtropical latitudes. The tribe is characterised most clearly by the aril of the seeds, which has a distinctive overarching lobe that connects to the funicle. Leaves are unifoliolate, trifoliolate or imparipinnate, stamens are uniform and mostly all fused to form an adaxially open sheath; calyx-lobes are imbricate in bud; and the standard and wing petals are yellow with varying patterns of reddish, brown or greyish pigmentation. Pods are mildly to strongly compressed and commonly become revolute post-dehiscence. Some species of Bossiaeadevelop flattened stems and may be leafless.

Historically, the Australian-endemic genera Hovea and Templetonia, now in tribe Brongniartieae, had been placed with the Bossiaeeae. However, more recent morphological and molecular studies have placed the Bossiaeeae as sister to or nested within tribe Mirbelieae.

Bossiaea comprises approximately 60 of the 72 species currently recognised in tribe Bossiaeeae, while the other five genera each currently comprise four or fewer species. Bossiaea is also the most widespread genus, although Goodiaand Muelleranthus also have widespread distributions. Muelleranthus,Ptychosema and Aenictophyton have predominantly eremean distributions, occurring predominantly in central latitudes and extending across much of the mainland. Goodia, Bossiaea and Platylobium, generally occupy regions of higher rainfall, although some species of Goodia and Bossiaea occur in arid or semi-arid areas.

The current classification of tribe Bossiaeeae will be reassessed in this project using morphological data and taking advantage of collections made since the most recent revisions in each genus. New species have been identified in most genera, and there are indications that changes to the generic classification are desirable. Papers describing the project findings are currently in preparation. Ultimately, it is expected that a complete treatment of tribe Bossiaeae will be produced for the Flora of Australia project.

Project team

  • Ian Thompson (Royal Botanic Gardens Melbourne, 2007–2012)

Project support

  • Australian Biological Resources Study (ABRS)