Malvaceae Info (Home)
Composition | Position | Division
Byttneriina is a clade roughly corresponding to elements of the traditional Tiliaceae and Sterculiaceae. It also contains the New Caledonia endemics Maxwellia (formerly placed in Durioneae) and Oceanopapaver (formerly assigned, by different authors, to Tiliaceae, Capparaceae, Papaveraceae, Cistaceae, or a monogeneric Oceanopapaveraceae).
The elements of Tiliaceae included in Byttneriina are the tribes Grewieae and Sparrmannieae. The elements of Sterculiaceae which are included in Byttneriina are the tribes Byttnerieae (including Kleinhovia), Theobromeae, Hermannieae and Lasiopetaleae. These elements of Sterculiaceae, plus the tribe Dombeyeae, were sometimes recognised as the family Byttneriaceae. However the tribe Dombeyeae does not fall into the Byttneriina clade.
In total Byttneriina has about 1200 species in about 50 genera. Approaching half of the species belong to the 4 largest genera (Grewia, Corchorus, Byttneria and Hermannia).
Bytteriina is an element of Malvaceae sensu APG. Within The Malvaceae Pages is it treated as the sister group to the remainder of Malvaceae (Malvadendrina). Alternatively it may be considered as one element in a 7 way polytomy with Malvatheca, Sterculioideae, Helicteroideae, Tilioideae, Brownlowioidea and Dombeyoideae. (The internal structure of Malvaceae is poorly resolved at several points, and further sequence data is awaited.)
The ndhF data set shows a clear division of Byttneriina into two clades - the Grewioideae (elements of traditional Tiliaceae) and Byttneroideae (elements of former Sterculiaceae). The further division of these into smaller clades (tribes) is less clear, but weakly supports a 6 tribe classification, with the former divided into Grewieae and Sparrmannieae, and the latter divided into Byttnerieae, Theobromeae, Hermannieae and Lasiopetaleae. Within published data set Kleinhovia is sister to the rest of Byttnerieae, and may warrant the retention of the tribe Kleinhovieae.
Elements of Grewioideae have been granted familial rank by some authors, under the name Sparrmanniaceae
Elements of the Byttnerioideae have also been granted familial rank by some authors, under the names Cacaoaceae, Hermanniaceae, Lasiopetalaceae, Melochiaceae and Theobromataceae.
Recently Thorne raised both subfamilies to the rank of family, as Grewiaceae and Byttneriaceae, in a classification which divided Malvaceae sensu APG into three families (the 3rd being Malvaceae).
The division between Grewieae and Sparrmannieae is not completely clear; a clade containing Heliocarpus and Triumfetta is only weakly associated with Sparrmannieae to the exclusion of Grewieae.
Byttnerieae is the sister group to the remaining 3 tribes, which form an unresolved trichotomy. Lasiopetaleae is divided into two distinct clades, and may not be monophyletic, though biogeographical evidence favours its monophyly.
A large tribe, with several hundred species.
A large tribe, with several hundred species. Includes one of the world's major fibre crops, Corchorus olitorius (jute).
A moderately sized tribe of about 270 species in 8 genera, mostly shrubs or climbers. Pantropical in distribution, but most diverse in the neotropics.
Also spelled Theobromateae. A primarily neotropical tribe, including a significant crop plant, Theobroma cacao (cacao). Confined to the neotropics, except for the monotype genus Glossostemun, which is found in North Africa and South West Asia. The neotropical genera are Theobroma, Herrania and Guazuma.
A moderately sized tribe, with a pantropical distribution, consisting of 4 genera - Hermannia, Waltheria, Melochia and Dicarpidium.
A moderately sized tribe, mostly confined to Australia, also including the New Caledonian endemic Maxwellia, and with a few species in Madagascar, Malesia and Melanesia. It is divided into two clades, which are perhaps worthy of the rank of sub-tribe, or even tribe. One is primarily temperate, and has a distribution centred on south west Australia (but also includes Maxwellia); the other is primarily tropical, and has a distribution centred in northern Australia. The former includes Thomasia, Lysiosepalum, Lasiopetalum, Guichenotia and Maxwellia; the latter Commersonia, Rulingia, Keraudrenia and Seringia.
Malvaceae Info (Home)
© 2002, 2003, 2004 Stewart Robert Hinsley