Alternanthera echinocephala

Description

Alternanthera echinocephala is a much-branched shrub up to 2 m (7 ft) tall. Its leaves are arranged oppositely and are narrow and pointed (lanceolate) with untoothed margins, 7-9 cm (2.8-3.5 in) long. The flowers are grouped into somewhat rounded spikes ("heads") about 10-15 mm (0.4-0.6 in) across. Each flower has one large and two small bracts below it, which form the most conspicuous part of the flower head. The bracts are greenish-white, sometimes with pinkish tones. The small sepals are similar in colour, only 5-10 mm (0.2-0.4 in) long. The flowers have no petals and five stamens. Thirteen species of Alternanthera are found in the Gal-pagos Islands, of which six are endemics; A. echinocephala is said to be easy to distinguish based on its relatively large flower heads with their spiny appearance.