Halimeda minima (W.R.Taylor) Hillis-Col.

Scientific Description

Habit and structure. Thallus to 18 cm tall (although varying considerably, depending on habitat), grass-green, drying pale olive-green to white, arising from a single holdfast, erect or pendant when growing on undercuts, sparingly dichotomously to trichotomously branched, with sequences of up to 10 unbranched segments. Segments mostly in one plane; basal segments terete to flattened, occasionally trilobed; others discoid, reniform or trilobed, mostly ribbed, often of a uniform size and shape throughout the thallus, 4–6 mm long, 5–9 mm wide. Utricles in 3 or 4 layers; secondary and inner utricles cylindrical and essentially undifferentiated, only slightly constricted if at all; peripheral utricles polygonal in surface view, (20–) 25–35 µm diam., cup- or goblet-shaped, not disassociating after decalcification. Medullary siphons 35–90 µm diam., fusing briefly in groups of 2, 3 or more at nodes; walls thickening and faintly brownish, with large pores developing at fusion sites.

Distribution. Widespread in the Indo-West Pacific.

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 135 (2015)]