Description: Thin sheet or cushion covering rock in patches to 15cm or more in diameter. Red to reddish-orange. Crumbly. The oscules are fairly regularly distributed and reasonably obvious because of the presence of converging channels.

Habitat: On vertical rock faces in exposed places with strong wave action or tidal streams.

Distribution: Known from the south and west coasts of Ireland: Saltee Is., Co. Wexford; Sherkin Is., Co. Cork; Rathlin O'Birne Is., Co. Donegal.

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

iNaturalist: Microciona fallax at iNaturalist World Species Observations database.