Chondria apiculata Huisman

Scientific Description

Habit and structure. Thallus soft and delicate, light pink, arising from a discoid holdfast, to 13 cm tall, with several percurrent axes bearing radially arranged lateral branches; ultimate branches fusiform when young, becoming clavate. All branches basally constricted, with rounded apices, but with an emergent pointed primary axis bearing a few trichoblasts. Trichoblasts rudimentary to well developed. All axes terete; main axes to 1.2 mm diam., tapering gradually to 350–300 µm diam. in distal regions, then to 150 µm diam. just below apices. Structure with 5 conspicuous pericentral cells, bearing outwardly 2–4 layers of cortical cells. Outer cortical cells longitudinally elongate in surface view [L:B 1.5–6].

Reproduction. Spermatangia in plate-like lateral stichidia, with a central region of spermatangia and a margin of a single row of sterile cells. Cystocarps sessile, to 900 µm diam., without a subtending spur. Tetrasporangia arising in a spiral pattern near branch apices, when mature c. 1/3 the width of the bearing branch, spherical, 120–190 µm diam., tetrahedrally divided.

Distribution. Known from Barrow Island and the Dampier Archipelago, Western Australia.

Habitat. Epilithic on sand flats in the subtidal.

[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 491–493 (2018)]