Malvaceae Info (Home)
The tribe Lasipetaleae is a division of subfamily Byttnerioideae of the angiosperm family Malvaceae. Within this subfamuly it is the sister group to the tribe Hermannieae.
Species of Lasiopetaleae are shrubs or less commonly small trees. The inflorescences are often oppositifoliate, in contrast to the axillary or terminal condition of most Malvaceae. Stamens are usually few in number (as many as the sepals), staminodes are commonly present, and the petals are frequently reduced or absent. The seeds are usually strophiolate.
Lasiopetaleae consists of the genera Commersonia, Guichenotia, Hannafordia, Keraudrenia, Lasiopetalum, Lysiosepalum, Maxwellia, Rulingia, Seringia and Thomasia, with about 150 species in total. Lasiopetaleae is almost exclusively Australian. The monotypic genus Maxwellia is endemic to New Caledonia, and one species of Rulingia (madagascarensis) and one of Keraudrenia (macrantha) are to be found in Madagascar. Commersonia bartrami is widely distributed from South East Asia to New Caledonia as well in northern Australia, and there is also a species of Commersonia endemic to New Guinea, and another endemic to Vanuatu.
Currently 10 genera are recognised, containing about 125 species in total. Several of these genera are not only Australian, but have a distribution concentrated in south west Australia. The genera are
The poorly known Pimia rhamnoides of Fiji may also belong to this tribe
ndhF cpDNA sequence data divides the tribe into two distinct groups, one consisting of the genera Thomasia, Lasiopetalum, Guichenotia, Hannafordia and Maxwellia, and the other of Seringia, Keraudrenia, Rulingia and Commersonia. No sequence data is available for Lysiosepalum, but the pattern of historical synonymy suggests that it should be placed in first group.
The detailed phylogeny of Lasiopetaleae is unknown, but work is in progress. Maxwellia is morphologically aberrant, but is placed deep within the tribe by DNA sequence data. The distinction between Rulingia and Commersonia (single versus compound staminodes) does not appear to reflect a natural division . The dividing line between Guichenotia and Lasiopetalum is also unclear [a].
Malvaceae Info (Home)
© 2006, 2007, 2008 Stewart Robert Hinsley