Description: A smooth rounded red sea squirt found in densely aggregated colonies. The small individuals have a common basal test, and increase in number by budding. The siphons have a six lobed appearance on partial contraction, which is distinctive. 5-8mm in diameter.

Habitat: Characteristic of the infralittoral, occurring on rock, kelp holdfasts and algae.

Distribution: Apparently a southern species in the British Isles, quite common on the south coast of England as far east as Dorset, and occurring on the west coast of Ireland. The record on the NBN map from Strangford Lough is likely to be Dendrodoa grossularia.

Similar Species: Easily and frequently mistaken for Dendrodoa grossularia, leading to confusion over distribution.

Key Identification Features:

• Dense aggregations of small shiny red individuals.
• 6-lobed appearance of siphons.
• Internal anatomy, with numerous small gonads scattered in body wall.

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

iNaturalist: Distomus variolosus at iNaturalist World Species Observations database.

GBIF data for Distomus variolosus

WoRMS: Distomus variolosus at World Register of Marine Species. Accepted name: Distomus variolosus Gaertner, 1774. AphiaID: 103890.

Classification: Biota; Animalia; Chordata; Tunicata; Ascidiacea; Stolidobranchia; Styelidae; Distomus