Manajú / Sea Purslane

Overview

Sea purslane or manajú (Sesuvium portulacastrum) is a low, creeping, succulent-leaved herb of high-salinity coastal habitats around the warm-water world. The stems are reddish, jointed and prostrate; they root at the nodes and form dense mats that can cover bare salt flat and stabilize sand. Leaves are smooth, fleshy and cylindrical-flattened — built like a true desert succulent because, ecologically, a salt flat is a physiological desert (water is abundant but unusable due to osmotic stress). Flowers are small but striking pink-to-magenta stars; capsules are tiny, with many seeds dispersed by both water and wind.

The species is pantropical — the same plant occurs on beaches in the Caribbean, West Africa, India, and the Pacific. It is also edible (the basis of the name “sea purslane”) and used in coastal cuisine in many parts of its range, though raw consumption requires desalting.

Why Tortuguero

Sesuvium portulacastrum sits in one of the harshest plant habitats in the park — the high-salinity, frequently flooded transition between beach and brackish estuary. Few plants tolerate this strip; Sesuvium is one of the reliable ones, alongside salt-tolerant grasses and the occasional young mangrove seedling washed in by tide.

Functionally, it traps sediment, holds the otherwise loose surface, and reduces evaporation from salt flats — modestly modifying the local microhabitat in ways that allow other species to colonize. This is the first link in many coastal-succession sequences.

How to see them (honestly)

• Look at the sand-to-mangrove transition at the river mouth and along sheltered estuary edges. The matted, reddish-stemmed groundcover with small fleshy leaves is Sesuvium.
• Easier to spot in flower — the pink stars stand out against the otherwise drab salt flat.
• The species is unmistakable once you’ve seen the stem-and-leaf combination; nothing else at the salt-flat zone looks quite like it.

Status note

IUCN classifies Sesuvium portulacastrum as Least Concern — its pantropical distribution and high reproductive capacity make it ecologically secure. Local pressures are coastal development, removal of salt-flat habitat for shrimp ponds or fill, and substrate disturbance. The species is one of the more resilient elements of the back-beach community: it tolerates trampling and recovers quickly from physical disturbance, which is part of why it persists on relatively used sections of beach.