ASCLEPIADACEAE

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 70

CXLIII. ASCLEPIADACEAE 1

Shrubs or perennial herbs, sometimes with twining stems. Leaves usually opposite, simple, exstipulate, sometimes scale-like. Flowers in axillary or terminal cymes or umbels, actinomorphic, 5-merous. Corolla-lobes contorted or valvate in bud. Single or double corona, of 5 or 10 free or more or less connate segments, inserted at the base of the filaments. Anthers united in a ring and usually adnate to the stigma, forming a gynostegium. Pollen in pollinia or tetrads, becoming attached to translators (pollen-transfer devices) which consist either of a cochleariform body and an elongate portion ending in an adhesive disc, or of 2 arms and a claw. Ovary superior; carpels 2, free below, united at the stigma. Fruit a pair of follicles, though often only one developing. Seeds comose at apex.

1 Corolla-lobes deflexed at anthesis; follicles usually spiny

2 Corolla white; leaves 2-10 cm 3. Gomphocarpus

2 Corolla pink or purple; leaves (10—>15—23 cm 4. Asclepias

1 Corolla-lobes patent or erect at anthesis; follicles not spiny

3 Corona double, with 10 segments

4 Stems stronglytwining;leavesherbaceous 5. Cynanchum

4 Stems not twining; leaves scale-like 8. Caralluma

3 Coronasingle,with5 segments

5 Corona-segments awned; anthers opening by longitudinal slits 1. Periploca

5 Corona-segmentsnotawned;anthersopeningby apicalpores

6 Corolla 15-20 mm in diameter 2. Araujia

6 Corolla 5-12 mm in diameter

7 Corona-segments ±united by a membrane; inflorescences few-flowered; pollinia pendent 6. Vincetoxicum

7 Corona-segments free; inflorescences many-flowered; pollinia erect 7. Cionura

Subfam. Periplocoideae

Anthers adjacent to, but not adnate to the stigma, opening by longitudinal slits; pollen in tetrads. Translators consisting of a cochleariform body and an elongate portion ending in an adhesive disc.