Gymnogongrus crenulatus J. Agardh
For a long timeknown as G. norvegicus, but this name, in the strict sense, has been shown to refer to Chondrus crispus and not to this entity
Description: Cartilaginous, fleshy, flattened, dark red fronds, 60-100 mm high, with short cylindrical stipe arising from basal disc. Repeatedly dichotomous, branches strap-shaped, apices blunt-rounded (see picture below), often noticeably paler than the rest of frond (above). Margins of frond irregular and sculpted. Reproductive structures appear as external, wart-like excescenses (see below).
Habitat: On sand-covered rocks, lower intertidal, southern and western coasts, often locally abundant. Often turning an unhealthy colour with prolonged exposure during particularly low tides.