Pterocladiella capillacea

Thallus caespitose, cartilaginous forming dense tangled tufts, (1.5–)3–15 cm high, dark purplish-red. Creeping axes terete, give rise to erect, lanceolate flattened axes to 2 mm wide. Branching distichous, 2–3 times pinnate, pyramidal in outline, with opposite or alternate branchlets. In transverse section, cortex composed of 1–2 rows of roundish or square cells, to 10 μm across; medulla composed of roundish to oblong cells 22.5–30×17.5–25 μm surrounded by slender thick-walled cells of rhizoidal filaments in the inner medulla, 3.5–5 μm diam. Tetrasporangia spherical or ovoid, 20–30 μm diam., cruciately divided. Cystocarps 250–300 μm diam., formed in the middle of branchlets on one side. Attachment by padlike rhizoids descending from creeping axes. Growing on intertidal to subtidal rocks.

Temperate and tropical waters.