Areschougia moniliformis Huisman

Scientific Description

Habit and structure. Thallus erect from a discoid holdfast, to 6 cm tall, dark red. Axes segmented, sparingly to regularly dichotomously (rarely trichotomously) branched; segments ellipsoidal to clavate, 3–5 mm long, 1.0–2.5 mm diam.; lower axes becoming terete and cartilaginous. Cells of the central axis very conspicuous, when mature 200–250 µm long and 70–100 µm diam. (including wall); each bearing a single periaxial filament from a medial or distal position. Periaxial filaments dichotomously branched and forming a sparse medulla. Cortex of 2 or 3 cell layers; innermost layer of large slightly flattened hyaline cells 25–35 µm wide, grading to an outer layer of subcuboidal pigmented cells, in surface view angular and 10–15 µm wide. Cortex in surface view with series of more elongate cells appearing as veins. Rhizoidal filaments forming a loose jacket around the central axis and a layer below the cortex, consisting of elongate cells 5–10 µm diam.

Reproduction. Reproductive structures not observed.

Distribution. Known from the type locality (Gnaraloo, Ningaloo, Western Australia) and an additional collection from Point Cloates.

Habitat. Benthic.

[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 154–156 (2018)]