|
Acanthaceae
Acanthus Family
By: George Rogers
A large mostly tropical family of about 2000 species and 200
genera (BA1) of herbs to shrubs having opposite simple leaves without stipules.
Stems often square with a small ledge connecting the leaf bases. Flowers usually
bilaterally symmetrical, typically with 4 or 2 stamens, the flowers often
associated with conspicuous bracts, these frequently spiny. Fruits distinctive:
two valves separating like the two halves of a clam shell, each valve with
fingerlike organs called “jaculators” protruding inward and helping in seed
dispersal. An extensive treatment
of Acanthaceae in Florida is available as "Acanthaceae in Florida Gardens" by D.
Burch and E. Demmy (Proc. Fl. Hort. Soc. 99: 186-188. 1986) presented on-line
at:
http://www.fshs.org/Proceedings/Password%20Protected/1986%20Vol.%2099/186-188%20(BURCH).pdf
Key to Acanthaceae Important in South Florida Landscaping
1. Leaves deep metallic purple…Persian-Shield (Strobilanthes
dyerianus)
1. Leaves otherwise…2
2. Plants vines…3 (note 6 possible choices for question 3)
2. Plants subshrubs or shrubs…4
3A. Flowers yellow…Black-Eyed Susan Vine (Thunbergia
alata)
3B. Flowers orange with a dark blotch in the throat…Hummingbird Vine (Ruttya
fruticosa)
3C. Flowers coral colored…Coral Creeper
(Barleria
repens)
3D. Flowers large (> 2” across), blue (rarely white); climbing
vine with entire leaf-margins, the blades green…Clock Vine (Thunbergia
grandiflora) (Thunbergia
battiscombei is similar but the flowers are purplish, and the plants are
smaller and less aggressive.)
3E. Flowers small (<1” across), white; sprawling vine with dentate-crenate leaf
margins, the blades partially purplish…Red-Ivy (Hemigraphis
alternata)
3F. Flowers to 5 cm long, the stigma cup-shaped, having sepal-like bracts and a
tiny multi-toothed calyx…Fragrant Clock Vine (Thunbergia
fragrans)
(See
Hemigraphis page for comments on
similar species.)
4. Leaves with parallel creamy-yellowish or white stripes
following the veins…5
4. Leaves green, or the markings not parallel stripes…6
5. Leaf stripes creamy; flowers in
loose spikes with small bracts…Sanchezia (Sanchezia
speciosa)
5. Leaf stripes white; flowers in
dense heads with congested yellow bracts…Zebra Plant (Aphelandra
squarrosa)
6. Flowers white and lost in a massive head of purplish bracts…Brazilian Cloak (Megaskepasma
erythrochlamys)
6. Plants otherwise…7
7. Flowering bracts showy bright yellow…Lollipop Plant (Pachystachys
lutea)
7. Flowering bracts not yellow or not apparent…8
8. Leaves multicolored…Caricature Plant (Graptophyllum
pictum)
8. Leaves green…9
9. Flowers and bracts white…White Candles (Whitfieldia
elongata)
9. Flowers and bracts otherwise…10
10. Woody shrubs; flowers strongly curved, the basal portion of the tube white,
the outer portion blue to purple with a yellow eye; leaves ovate…Kings Mantle (Thunbergia
erecta)
10. Plants otherwise…11
11. Flowers orange…12
11. Flowers otherwise…13 (note 3 choices)
12. Orange flowers with black markings in the throat…Hummingbird Vine (Ruttya
fruticosa)
12. Orange flowers with no black markings…17
13A. Flowers scarlet…14
13B. Flowers bright yellow…Yellow Barleria (Barleria
oenotheroides)
13C. Flowers otherwise…15
14. Spikes with conspicuous bracts…Cardinal's Guard (Pachystachys
coccinea)
14. Spikes with bracts absent or not conspicuous…Firespike (Odontonema
tubaeformae) (some have purple flowers)
15. Flowers usually purplish or white, variably colored, the bracts
spiny…Philippine-Violet (Barleria
cristata)
15. Bracts not spiny…16
16. Flowers nearly blue-lavender in dense bracteate spikes…Blue Sage (Eranthemum
pulchellum)
16. Flowers not blue or lavender, or not in dense bracteate
spikes…Mexican-Petunia (Ruellia simplex)
17. Plants 2’ tall, the petals spreading into a fan shape…Firecracker (Crossandra
infundibuliformis)
17. Plants to 7' tall. Flowers
narrowly tubular…Mexican Honeysuckle (Justicia
spicigera)
Other plants in the manual include:
Hygrophila polysperma
|
