Crouania dampieriana Huisman

Scientific Description

Habit and structure. Thallus to 50 mm tall, light pink to dirty red, accumulating sediment and apparently occasionally lightly calcified; all axes generally with a distinct mucilage coating, although this occasionally absent. Structure filamentous, with erect and decumbent axes; indeterminate lateral branches arising from the distal end of axial cells. Whorl branches curved towards the apex, generally obscuring the axial filament but often not, unequally tri- to tetrachotomous at the basal cell, then trichotomous and ultimately dichotomous, but with 1 or 2 percurrent primary branches; terminal branch 1- or 2-celled, with elongate or ellipsoidal cells. Older parts of the thallus with whorl branches separate.

Reproduction. Spermatangia forming on outer cells of whorl branches. Developing cystocarp not resulting in cessation of growth of bearing branch, when mature the cystocarp well below the branch apex and appearing to cause a swelling due to growth of associated whorl branches. Gonimoblasts arising in clusters of up to 3 gonimolobes, each to 250 µm diam. and composed entirely of carposporangia 25–35 µm diam. Tetrasporangia borne singly or in sequentially maturing pairs on the basal cells of whorl branches, occasionally on more distal cells, spherical, 35–60 µm diam., tetrahedrally divided.

Distribution. Common in north-western Australia.

Habitat. Epiphytic and epilithic in the intertidal and shallow subtidal.

[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 362–364 (2018)]