Species description: A 6-plated barnacle that often has a red to pink colouration, especially at upper end of the outer body. Can be up to 12 mm in diameter but is often smaller, with a relatively large opercular opening. Outer body made up of 6 plates with a number of thin, vertical pink to red stripes, sometimes there are also horizontal stripes or streaks.

Habitat: A warm water species that is most often found on a range of mobile hard substrata such as marine litter, leisure craft or molluscs (e.g. whelks or scallops).

Distribution: So far all records are confined to the SW of Britain.

Similar Species: Could be confused with Amphibalanus amphitrite but that species has a much neater pattern of stripes and has four distinctive dark bands running across the tergo-scutal flap. Could potentially be confused with Perforatus perforatus but this is much more conical in shape and doesn’t have the same pattern of stripes and streaks, although it can have an overall pale pink colouration with darker lines.

Key Identification Features:

• 6-plated barnacle with a red to pink colouration, which is paler towards the rostrum.
• Plates have a number of vertical pink to red stripes, occasionally also some horizontal stripes or streaks.
• Does not have four dark bands running across tergo-scutal flap.

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

iNaturalist: Solidobalanus fallax at iNaturalist World Species Observations database.

WoRMS: Solidobalanus fallax at World Register of Marine Species. Accepted name: Solidobalanus fallax (Broch, 1927). AphiaID: 106208.

Classification: Biota; Animalia; Arthropoda; Crustacea; Multicrustacea; Thecostraca; Cirripedia; Thoracica; Thoracicalcarea; Balanomorpha; Balanoidea; Balanidae; Archaeobalaninae; Solidobalanus