Australian Tropical Rainforest Plants - Online edition
Aeschynomene americana L.
Linnaeus, C. von (1753) Species Plantarum : 713. Type: Lecto: Jamaica, B. W. I., Sloane. Fide V. E. Rudd, Contr. U.S. Nat. Herb. 32 (1955) 23-30.
Flowers and fruits as a herb or a shrub about 1-2 m tall.
Stipules +/- peltate, about 10-13 mm long, narrow, margins clothed in hairs, two-branched, longitudinally veined. Each compound leaf with 50-60 leaflets. Compound leaf axis clothed in long hairs, axes ending in a short point. Leaflets sessile, (or almost sessile) blades about 6-12 x 1-2 mm, margins hairy, with a small tooth on one side. Venation longitudinal and parallel with 3-5 longitudinal veins.
Each flower subtended by two hairy, lanceolate bracts each about 2-2.5 mm long. Calyx 4-4.5 mm long, lobes 2. Petals clawed, i.e. stalked. Stamens 10, filaments all fused to form a tube open on one side. Filament about 4 mm long, attached close to the base of the anthers. Pollen orange. Ovules 6-10 in each ovary.
Fruits about 2.5-3 cm long, clothed in simple, erect hairs. Fruits consist of a string of 2-8 segments each containing one seed. Segments attached on one side of a 'bean string' and breaking off as one-seeded nuts. Seeds glossy brown, about 3 x 2 mm. Embryo about 1.4-2 mm long. Cotyledons about 1.5 mm long. Radicle about 0.75 mm long.
Cotyledons ovate to elliptic, about 7 x 5 mm. Petioles less than 1 mm long. First pair of leaves compound with 13-20 leaflets, each leaflet about 4-6 mm long. At the tenth leaf stage: leaf compound with about 50-60 closely-spaced leaflets. Leaflets linear, about 10-15 x 2-3 mm. Leaflet margin with several hair-like teeth near the apex. Compound leaf petiole distinctly kinked about halfway along its length. Stipules hairs, medifixed with a total length about 15 mm, Each arm about 5-8 x 2 mm. Seed germination time 7 days.