Peyssonnelia confluens K.R.Dixon

Scientific Description

Habit and structure. Thallus pinkish to orange-red, extensively calcified internally, composed of closely and tightly appressed tuberculate crusts, with adventitious encrusting blades occasionally forming from the dorsal surface, to 550 µm thick. Hypothallus poorly defined, the filaments irregularly orientated and often indistinct. Perithallus composed of dorsally assurgent filaments, the lower cells thick-walled and heavily calcified, roughly isodiametric, 8–18 µm diam., but irregularly shaped due to numerous fusions with adjacent cells. Epithallus compact, deeply pigmented, composed of c. 6 tiers of relatively thin-walled cells c. 12.5 µm diam. [L:B <1, becoming 0.25–0.5 distally]. Rhizoids infrequent, short, clavate, c. 12 µm diam.

Reproduction. Reproduction not observed.

Distribution. Known from only a few collections from Adele Island, north-western Australia.

[After K.R. Dixon in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 220−221 (2018)]