Ipomoea cairica (L.) Sweet

Global description

Ipomoea cairica is a creeping and climbing herbaceous liana that can completely cover a tree or shrub. Tuberized root and fasciculate roots at the nodes of the stem in contact with the ground. Brown reddish hairless stem, woody at the base. Leaves simple and alternate. Petiole as long as limb. Leaves glabrous with palmate blade cut into 5 deeply indented segments. Edge of the limb smooth. The flowers are purple, cone-shaped, clustered at the end of small secondary branches. The corole consists of 5 petals welded in a thin tube at the base and which is widening. The fruit is an oval capsule (1 cm in diameter) dehiscent slightly apiculate, which opens in 4 valves and contains 4 seeds covered with a strong pubescence.

Cotyledons


The cotyledons are remarkable for their V-shape with narrow branches. They are stalked at the base. The branches with obtuse apex, are traversed by 2 parallel longitudinal ribs, a little prominent on the upper face.

First leaves

The first leaves are alternate, simple and deeply cut into 3 or 5 well individualized lobes. The seedling is smooth and hairless. Its stem becomes progressively twitchy.

General habit

It is a lianascent, vivacious herb with a ramified twining stem that can reach up to 8 m long.

Underground system

Tuberized rhizomes and fairly developed roots.

Stem

The stem is cylindrical with a diametre of 2 to 3 mm (up to 12 mm in an old plant), branched, it is 2 to 5 m long, but can reach up to 8 m. Young twigs are very twining, with a tendency to curl from left to right. It is glabrous, smooth and has small warty asperities.

Leaf

The leaves are alternate and simple. The petiole is 2 to 10 cm long, it often has a base of more or less deciduous pseudostipules, which have been reduced. The blade smooth and glabrous, circular in shape, palmatilobate with lobes whose base reaches almost the petiole. The lamina seems digitate. It is 2 to 8 cm wide by 2 to 9 cm long. The lobes, 5 to 7, are narrow ovate elliptic, with apex acute or obtuse acuminate and mucronate, attenuated at the base. The median lobe is bigger.

Inflorescence

Solitary axillary flowers or few-flowered cyme (2 to 5 flowers).

Flower

Floral pedicels 1 to 2 cm long are borne by peduncles 0.5 to 8 cm. The calyx is composed of 5 to 6 oval sepals subacute to obtuse or round mucronate, 10 mm long, arranged in 2 rows. They are green, with scarious margin. The funnel corolla, with a long tube of 5 to 6.5 cm, is widely spread at the top. It reaches 7 to 8 cm in diameter. It is typically pale purple or white with purple throat but can be entirely white. The 5 stamens unequal, 3 small and 2 large, are included in the tube and welded at its base. The conical ovary is prolonged by a style of 10 to 12 mm long.

Fruit

The fruit is a globose capsule 10 to 15 mm in diameter, with 4 apiculate valves. The sepals are persistent. It contains 4 seeds.

Seed

The seeds are trigonal-globular. They are 5 to 6 mm long and 4 to 5 mm thick. The tegument is dark brown, pubescent, with a white pubescence more developed on the angles.

https://www.gbif.org/fr/species/2928531