Description: The gametangial thallus is somewhat flattened and much branched to 30 cms in length, opposite lateral branches alternately unequal in length. The tetrasporangial phase is a prostrate crust.

Habitat: Both the gametangial and tetrasporangial phases are low littoral or sublittoral to 15 m.

Distribution: Generally found around the British Isles: England, except the eastern coast, Ireland, Wales and Scotland including the Shetlands, the Isle of Man and the Channel Isles. Europe: Mediterranean, Portugal to Norway. Further afield: Morocco.

Similar Species: Bonnemaisonia hamifera can be distinguished by its large hooks by which it attaches itself to other algae.

Distribution Map from NBN: Bonnemaisonia asparagoides at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Bonnemaisonia asparagoides at iNaturalist World Species Observations database.

WoRMS: Bonnemaisonia asparagoides at World Register of Marine Species.