Description: Thalli arising from a small attachment disc to form small fronds which devide dichotomously into flattened branches 10 cms (or more) long. Often with an interrupted midrib formed by cystocarps.

Habitat: Epilithic and on shells, sublittoral to 13 m deep.

Distribution: Generally south-western in the British Isles, south Wales, south-west England, the most northerly records being from Northern Ireland. Europe: Azores, Portugal and Spain. Further afield: Canary Islands, widely in the Pacific.

Similar Species: Specimens without a mid-rib resemble Rhodymenia pseudopalmata.

Key Identification Features:

• The mid-rib is a distinguishing feature when the plants have developing cystocarps.

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

iNaturalist: Stenogramme interrupta at iNaturalist World Species Observations database.