Halimeda heteromorpha N'Yeurt

Scientific Description

Habit and structure. Thallus to 5 cm tall, green, drying a pale olive- green, thick-set, growing from a limited fibrous holdfast attached to rock, mostly dichotomously or trichotomously branched, but some segments bearing up to 6 branches. Holdfast with 1 or 2 basal segments, these terete to compressed, bearing 1–4 suprabasal segments. Segments dull, rugose, mostly cuneate, occasionally lobed, with crenulate or incised margins, 4–7 mm long, 5–9 mm wide. Utricles in 2 or 3 layers; peripheral utricles pyriform or goblet-shaped in side view, polygonal in surface view, 40–75 µm diam., occasionally fusing laterally; outer wall sometimes slightly convex. Medullary siphons 40–100 µm diam., fusing and forming an adhesion belt at the nodes, communicating by small oval pores 25–30 µm diam.

Distribution. Widespread in the Indian and Pacific Oceans.

Habitat. Epilithic in the intertidal and subtidal.

[After Huisman & Verbruggen, Algae of Australia: Mar. Benthic Algae of North-western Australia, 1. Green and Brown Algae 131 (2015)]