24. Cryptostegia R. Brown, Bot. Reg. 5: plate 435. 1820.
[I]
Rubbervine [Greek kryptos, hidden, and stegein, to cover, alluding to enclosure of five-scaled crown within corolla tube]
Casie L. Reed
Alexander Krings
Lianas or subshrubs; latex white. Stems climbing or with self-supporting branches, unarmed, glabrous or eglandular-pubescent. Leaves persistent, opposite, petiolate; stipular colleters interpetiolar and intrapetiolar; laminar colleters absent. Inflorescences terminal cymes, pedunculate. Flowers: calycine colleters present; corolla white, pale pink, or purple-pink, infundibuliform, aestivation dextrorse; corolline corona 2-fid or entire; androecium and gynoecium not united into a gynostegium; stamens inserted at base of corolla tube; anthers connivent, adherent to stigma, connectives apiculate, locules 4; pollen in tetrads, not massed into pollinia, but shed onto translators; nectary absent. Fruits follicles, paired, deflexed, green to brown, fusiform, strongly 3-angled, striate or smooth, glabrous or minutely pubescent. Seeds oblong, flattened, not winged, not beaked, comose, not arillate. x = 11.
Species 2 (2 in the flora): introduced; Indian Ocean Islands (Madagascar); introduced also in Mexico, West Indies, Bermuda, Central America, South America, Asia, Africa, elsewhere in Indian Ocean Islands, Pacific Islands, Australia.
Cryptostegia is endemic to Madagascar, but its two species have been introduced pantropically. Hybrids between C. grandiflora and C. madagascariensis have been reported in cultivated landscapes in Florida. There is no evidence that these hybrids have become naturalized.
SELECTED REFERENCES Klackenberg, J. 2001. Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia 23: 205–218. Marohasy, J. and P. I. Forster. 1991. A taxonomic revision of Cryptostegia R. Br. (Asclepiadaceae: Periplocoideae). Austral. Syst. Bot. 4: 571–577.
