Author:
Qjure
Book:
Qjurious
Type:
Info
Chapter:
3-655.30.00
Malvales
English: Malva order.
Members: 204 genera; 2300 species.
Content: sesquiterpenes; sesquiterpene quinones; thorbromine; caggeine; flavonols; cyclopropenoid fatty acids; mucilage!; oxytocin.
Use: ropes, fibres, cotton, kapok, jute; fruits and flavourings, cacao, cola, durian, okra; timber of linden, basswood, balsa; ornamentals like Althaea, Ceiba, Hibiscus, Malva, Lavatera.
Botany
Stem phloem stratified with fibrous and soft layers; bark fibrous and tough.
Leaves: with malvoid teeth, palmate; stipulate; lobed; simple; entire.
Flowers 5 connate sepals, 5 petals; stamens numerous, adnate to gynoecium; develop centrifugally from a few bundles; nectaries of glandular hairs; typical infloresence; epicalyx of bracts.
Fruit: inside wall often hairy, hairs stellate.
Seeds: oily or starchy; with woolly appendices.
Taxonomy
The order of the Malvales has been established a long time. But the exact placement has been problematic. It was for a long time thought to be connected with the Rosales. In the Cronquist system Malvales included Malvaceae, Sterculiaceae, Bombacaceae, Tiliaceae and Elaeocarpaceae
Numerous molecular phylogenies have shown that those families as traditionally defined are paraphyletic and closely related. This has resulted in expanding Malvaceae to include the other families. The traditional families are now treated as subfamilies of the extended Malvaceae. The membership though of many genera has been transferred to other subfamilies and new subfamilies have been created:
Byttnerioideae, Grewioideae, Sterculioideae, Tilioideae, Dombeyoideae, Brownlowioideae, Helicteroideae, Malvoideae, Bombacoideae.
In the Apg3 classification 3 groups can be distinguished in Malvales: the Families Thymelaeaceae and Neuradaceae that are early diverging, Cistales and Malvaceae.
In the Plant theory the order of the Malvales is split into 3 clades: Malvales, Cistales and Thymelaeaceae with Neuradaceae. Malvales is placed in Phase 3 of Malvidae. Cistales, with Cistaceae and Dipterocarpaceae is placed in Phase 5 of Malvidae. Thymelaeaceae and Neuradaceae are placed in Huerteales in Phase 2.
The extended Malvaceae is raised to the level of Order, Malvales and the subfamilies are treated as families.
Subphases
1. Sterculiaceae.
2. Malvioideae
3. Malvaceae.
4. Tiliaceae.
5. Bombacaceae.
6. Byttneriaceae
7. Grewiaceae.