Boodlea vanbosseae Reinbold

Scientific Description

Habit and structure. Thallus forming low mats or cushions, medium to dark green, to 1–2 cm thick and often spreading laterally to the extent of the available substratum. Thallus with numerous straight or curved filaments, these densely entangled and attached to one another by rhizoids or attachment pads. Rhizoids formed terminally or laterally, often with crenulate attachment pads. Branching irregular; lateral branches arising almost perpendicular, singly or in pairs from distal end of bearing cell, cut off by a cross wall that remains almost vertical. Older nodes with basal cell of laterals in contact with bearing cell and adjacent distal cell, forming a ‘Y’ joint. Apical cells cylindrical with rounded tips, 150–240 µm in diameter, L:B 2–4. Cells of main axes are 190–340 µm in diameter, L:B 1.5–4. Rhizoidal cells 70–100 µm in diameter, up to 4200 µm long. Cell walls ca. 5 µm thick in apical cells, up to 16 µm thick in main axes, giving the thallus a rigid texture. Chloroplasts angular, 5–8 µm in diameter, interconnected by delicate strands to form a parietal network, each with a single pyrenoid, 4–5 µm in diameter. Many cells infected with a fungus (Ascomycota) growing inside the cell, on the distal face of the cross walls. Fungal thalli up to 800 µm high, composed of branched hyphae 8–12 µm in diameter.

Distribution. Known from several locations in the tropical waters of the Indian and West Pacific Oceans. In Australia from northern W. Aust., and south-eastern Qld.