- Kingdom: Plantae
- Phylum: Rhodophyta
- Class: Florideophyceae
- Order: Bonnemaisoniales
- Family: Bonnemaisoniaceae
- Scientific name: Bonnemaisonia hamifera
- Norwegian: rødklo, krokbærer
Brownish red, feathery fronds, sometimes cover the sea bed, like cotton wool. The flattened stipe is only 1 mm wide, but may reach a length of 35 cm.
It is usually found during spring in the lowest tidal or in the subtidal zones. It seems to prefer sunny locations.
It was probably introduced in Europe from the western Pacific, late in the 19th century. It is known from the western Pacific, North-East Atlantic Ocean and the Mediterranean.