Contains 7 accepted taxa overall.
Characteristics
This genus is being revised, and some species (i.e. sect. Furcaria, sect. Muenchhusia, sect. Trionum) will move to other genera (Hanes et al. 2024).
Classification
Citation
HIBISCUS Linnaeus, Sp. Pl. 693. 1753, nom. cons.
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TYPE: Hibiscus syriacus Linnaeus, typ. cons.
Species
| Scientific Name | Common Name | Herbarium Specimens | Status | Photos |
|---|---|---|---|---|
| Hibiscus aculeatus | Savanna Hibiscus, Comfort-root | |||
| Hibiscus coccineus | Scarlet Hibiscus | |||
| Hibiscus grandiflorus | Large-flowered Hibiscus | |||
| Hibiscus laevis | Smooth Rose-mallow, Halberd-leaved Marsh-mallow, Showy Hibiscus | |||
| Hibiscus moscheutos | Eastern Rose-mallow | |||
| Hibiscus syriacus | Rose-of-Sharon, Althaea | |||
| Hibiscus trionum | Flower-of-an-hour, Venice Mallow |
Identification Key
1. Largest leaf blades to 6.5 cm long, to 7 cm wide; corolla 1.6-3(-4) cm long; fruit 1-1.5 cm long
2
1. Largest leaf blades to 30 cm long, to 30 cm wide; corolla 3-14 cm long; fruit 1.2-3.5 cm long
3
2. Plants perennial; leaf blades shallowly 3-lobed to unlobed, coarsely dentate; flower nodding or pendulous; primary veins of calyx not zigzag; corolla red
2. Plants annual; most leaf blades 3-5 lobed, the lobes pinnately undulate to lobed; flowers ascending to erect; primary veins of calyx zigzag; corolla cream, yellow, to purplish with purple-brown basal spot
3. Leaf blade lower surface conspicuously tomentose or scabrous
4
3. Leaf blade lower surface glabrous or with few hairs or prickles along veins
9
4. Leaf blade scabrous
4. Leaf blade tomentose
5
5. Stems densely tomentose; calyx often hispid; epicalyx bract bifid at the apex
5. Stems glabrous to densely tomentose; calyx tomentose; epicalyx bract not bifid at the apex
6
6. Leaf blade unlobed to lobed, the margins coarsely, irregularly crenate-dentate, the inner pair of lateral veins divergent from the midrib >45 degrees
7
6. Leaf blade usually unlobed, the margin regularly dentate, the inner pair of lateral veins ascending at an angle <45 degrees to the midrib
8
7. Pedicel and calyx eglandular; free portion of filaments secund; capsule apex apiculate; seeds verrucose-papillose
7. Pedicels and calyx glandular-hairy; free portion of filaments not secund; capsule apex impressed; seeds with long straight hairs dorsally and dorsolaterally
8. Upper and lower leaf blade densely tomentose and usually concolorous; epicalyx densely coarsely pubescent with both short-stellate hairs and longer spreading simple hairs especially near the margins; capsules densely pubescent throughout
8. Upper leaf surface glabrous or sparsely pubescent, darker than the tomentose lower surface especially when dry; epicalyx uniformly, minutely canescent; capsules glabrous or sparsely pubescent on sutures
9. Epicalyx bract setose, lobed, or bifid
10
9. Epicalyx bract entire
12
10. Nectary absent on leaves and calyx
10. Nectary present on midrib of leaf blade lower surface and calyx lobe midrib
11
11. Stems and leaves often dark red; epicalyx bract sometimes appendaged; corolla reddish with darker veins and base
11. Stems and leaves generally green, sometimes with red veins; epicalyx bracts without an appendage; corolla yellowish, often with a dark purple center
12. Leaf blade unlobed
13
12. Leaf blade lobed, usually at least some
14
13. Flowers horizontal to declinate; petals not pinnatifid-laciniate, spreading or slightly reflexed; epicalyx bract 0.3-3 cm long
13. Flowers pendulous; petals pinnatifid-laciniate, strongly reflexed; epicalyx bract to 0.2 cm long
14. Usually at least some leaf blades 3-lobed with lateral lobes perpendicular to the midrib
14. Leaf blades with 3-5 palmately radiating lobes or the inner lateral lobes ascending
15
15. Leaf blades with 3-5 palmately radiating lobes; petals red
15. Leaf blades unlobed to shallowly 3-lobed; petals white to pink or bluish
Genus Synonyms
| Synonym | Full Citation | Basionym | Type |
|---|---|---|---|
| No synonyms found. | |||