Malvaceae
Malvaceae (incl. Tiliaceae)
As here circumscribed the family Malvaceae is treated in a broad sense as to include Tiliaceae, in accordance with updated phylogenetic research (see for instance Alverson & al. 1999, Bayer & Kubitzki 2003).
Useful and up-to-date additional information on the Malvaceae family is available at: www.malvaceae.info
1. Tall trees. Flower stalks fused into a large narrowly oblong papery persistent bracteole dispersed with the fruit. Stamens fascicled but not united === Tilia
1. Herbs or shrubs. Flower stalks not fused into a persistent bracteole. Stamens united in a column === 2
2. Epicalyx absent === 3
2. Epicalyx present === 6
3. Style branches linear, not ending in capitate stigmas. Petals rose to pink. Perennial. Leaves (at least upper) divided in narrow segments === Sidalcea
3. Style branches ending in capitate stigmas. Petals variably coloured (yellow, blue or pinkish). Annual or (more rarely) perennial. Leaves never divided in narrow segments === 4
4. Mericarps with several seeds. Leaves palmately veined, densely felted hairy (at least when young) === Abutilon
4. Mericarps with one seed. Leaves pinnately or palmately veined, not felted hairy === 5
5. Petals bluish-purple (more rarely white or pinkish). Leaves hastate, palmately veined. Mericarps 10-20. Fruit a disk-like schizocarp, much enlarged in fruit (up to 30 mm across at maturity) === Anoda
5. Petals yellow. Leaves simple, pinnately veined. Mericarps 5-14. Fruit not conspicuously enlarged in fruit === Sida
6. Fruit a dehiscent capsule with 5 carpels === Hibiscus
6. Fruit a schizocarp (breaking up into several mericarps at maturity), with more than 5 carpels === 7
7. Epicalyx segments 6-10 === 8
7. Epicalyx segments 3 === 11
8. Robust, sticky-hairy perennial (up to 3 m tall). Leaves with 5-7 triangular, dentate lobes, long petiolate. Flowers axillary, peduncles 40-80 mm long. Petals white, ca. 25 mm long. Mericarps in several whorls, forming a spherical head === Kitaibela
8. Annual or perennial, not sticky hairy. Mericarps in a single whorl, forming a disc === 9
9. Petals 30-60 mm. Staminal column angled, glabrous === Alcea
9. Petals 10-20 mm. Staminal column terete, pubescent === 10
10. Perennial. Indumentum of stellate hairs only. Nutlets hairy (native) === Althaea
10. Annual. Indumentum of both simple and stellate hairs. Nutlets glabrous === Malva p.p. (incl. annual species of Althaea)
11. Petals yellow or orange-red === 12
11. Petals pink, salmon, purple, blue or white === 13
12. Stem erect. Flowers sessile or very shortly pedicellate in spikes or racemes. Petals yellow. Leaves serrate to crenate === Malvastrum
12. Stem prostrate to procumbent, rooting at nodes. Flowers solitary, pedunculated. Petals orange-red. Leaves shallowly lobed === Modiola
13. Mericarps in a single whorl. Epicalyx segments often narrower than sepals, linear to ovate === 14
13. Mericarps in irregular whorls in a globose head. Epicalyx segments at least as wide as sepals, ovate to orbicular === Malope
14. Stigma filiform. Corolla pink, purple, blue or white, never salmon. Plant glabrous to hairy, rarely velvety === Malva p.p. (incl. Lavatera)
14. Stigma capitate. Corolla salmon to pink. Entire plant stellate-velvety === Sphaeralcea
Literature
Alverson W.S., Whitlock B.A., Nyffeler R., Bayer C. & Baum D.A. (1999) Phylogeny of the core Malvales: evidence from ndhF sequence data. Am. J. Bot. 86: 1474-1486.
Bayer C. & Kubitzki K. (2003) Malvaceae. In: Kubitzki K. & Bayer C. (eds.), The families and genera of vascular plants, vol. 5. Springer Verlag, Berlin: 225-311.
Hanes M.M. (2015) Malvaceae. In: Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, vol. 6. Oxford University Press, New York: 187-375. [available online at: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=10534]