Species description: This erect bryozoan forms dense colonies of bushy, irregular tufts and is cream to buff in colour, although can very often be covered in silt. Tufts are 1-4 cm in height. It has thin branches composed of alternating zooids, and the branches themselves are alternately branching. Ovicells have small, round pores, and they may occasionally have a two-pronged spine opposite these ovicells.

Habitat: Attached to artificial substrata in harbours and marinas, also on kelps and Sargassum muticum. Can occasionally be found on shores attached to hard substrata or algae.

Distribution: First recorded in Northern Ireland in 2011, from Bangor marina and Portrush harbour. Now present in Strangford Lough, Ardglass, Bangor, Carrickfergus, Glenarm, Rathlin, Ballycastle and Portstewart marinas. Some records in south and south-east of Ireland. Many records in southern Britain, and some scattered records in Scotland.

Similar Species: Could be confused with Scrupocellaria spp. or Bugulina spp., although Bugulina spp. have birds head avicularia which are absent in Tricellaria and Scrupocellaria spp. have whip-like vibracula that Tricellaria lacks.

Key Identification Features:

• Forms dense colonies of bushy, irregular tufts.
• Cream to buff in colour, but often covered in silt.
• Thin alternating branches, composed of alternating zooids.
• Small round pores on ovicell.

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

iNaturalist: Tricellaria inopinata at iNaturalist World Species Observations database.

WoRMS: Tricellaria inopinata at World Register of Marine Species. Accepted name: Tricellaria inopinata d'Hondt & Occhipinti Ambrogi, 1985. AphiaID: 111254.

Classification: Biota; Animalia; Bryozoa; Gymnolaemata; Cheilostomatida; Flustrina; Buguloidea; Candidae; Tricellaria