Malvaceae subfam. Byttnerioideae

Burnett

Outlines Bot., 821, 1119. 1835.

Treatment appears in FNA Volume 6. Treatment on page 202. Mentioned on page 188, 197.

Herbs, subshrubs, shrubs [trees]. Leaf-blades usually unlobed, rarely lobed (Hermannia), margins serrate, dentate, or entire. Inflorescences axillary, terminal, or leaf-opposed, usually antisepalous or absent (Hermannia and Waltheria); gynoecium syncarpous. Fruits capsules or schizocarps, dehiscence loculicidal or septicidal. Seeds (1–) 5–10, usually glabrous.

Distribution

North America, Mexico, West Indies, Central America, South America, Asia, Africa, Australia, pantropical

Discussion

Genera 26, species ca. 650 (4 genera, 16 species in the flora).

Byttnerioideae comprise five tribes previously ascribed to the family Sterculiaceae (B. A. Whitlock et al. 2001). It is sister to Grewioideae; together they represent the earliest branching taxa in the family (C. Bayer et al. 1999; R. Nyffeler et al. 2005).

Selected References

None.

Key

1 Anthers 3-thecate; staminodes present; sepals distinct or connate. Ayenia
1 Anthers 2-thecate; staminodes usually absent; sepals connate > 2
2 Ovules 4–14 per locule. Hermannia
2 Ovules 2 per locule > 3
3 Ovaries 5-locular. Melochia
3 Ovaries 1-locular. Waltheria
Margaret M. Hanes +
Burnett +
lobed +  and unlobed +
septicidal +, loculicidal +  and dehiscence +
North America +, Mexico +, West Indies +, Central America +, South America +, Asia +, Africa +, Australia +  and pantropical +
sparse;copious +
actinomorphic +
unisexual +  and bisexual +
septicidal +, loculicidal +  and dehiscence +
antisepalous +, leaf-opposed +, terminal +  and axillary +
connate +  and distinct +
simple +, stipulate +, sessile +, subsessile +  and petiolate +
distichous +  and alternate +
entire +, dentate +  and serrate +
(1-)2-many +
5 +  and 4 +
Outlines Bot., +
septicidal +, loculicidal +  and dehiscence +
Mallow +
Malvaceae subfam. Byttnerioideae +
Malvaceae +
subfamily +
shrub +, subshrub +  and herb +