Echinophycus minutus Huisman

Scientific Description

Habit and structure. Thallus to 25 mm tall, partially decumbent, attached to the substratum by unicellular rhizoids. Axes terete, c. 35 µm diam. near the apices [segments L:B c. 0.7] and broadening to 200 µm near the base [segment L:B 1.2]. Trichoblasts in clusters of 4–7 from each basal cell, 5–7 cells and 700–950 µm long, with a short (to 20 µm long) mucronate apical cell.

Reproduction. Spermatangial heads ovoid to elongate, 95–125 × 60–95 µm. Spermatangia rod-shaped or clavate, 7–9 × 2 µm. Cystocarps spherical to ovoid, 200–220 µm diam.; pericarp bearing a trichoblast cluster. Tetrasporangia spherical, to 75 µm diam., with 2 pre-sporangial cover cells and 1 post-sporangial cover cell.

Distribution. Known only from the type locality and collection (Malus Island, Dampier Archipelago, Western Australia), which was dredged from a coarse sand/rubble habitat.

Habitat. Growing on an unconsolidated substratum.

[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 506 (2018)]