Description: This solitary ascidian can grow alone or form very dense clusters. It reaches up to 3 cm in size although commonly found in the 1-3 cm size range. The test is an indistinct grey to green colour and the body is quite stout and spherical with long siphons giving it a 'teapot-like' appearance. Careful inspection of features of the reproductive system may be required to distinguish this species. In M. socialis the testis overlies the surface of the ovary and there is a single large testis follicle with a single male gonopores adjacent to the female gonopore.

Habitat: Hard substrata (e.g. bedrock, boulder or shells) including artificial substrata, down to around 90 m.

Distribution: Scattered records from around Britain and Ireland, potential identity confusion with Molgula manhattensis could make true distribution uncertain.

Similar Species: Could be confused with Molgula manhattensis, careful inspection of testis and male gonopores may be required.

Key Identification Features:

• Solitary ascidian with stout spherical body and long siphons.
• Single large testis follicle with single male gonopores adjacent to female gonopore.

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

iNaturalist: Molgula socialis at iNaturalist World Species Observations database.

GBIF data for Molgula socialis

WoRMS: Molgula socialis at World Register of Marine Species. Accepted name: Molgula socialis Alder, 1863. AphiaID: 103804.

Classification: Biota; Animalia; Chordata; Tunicata; Ascidiacea; Stolidobranchia; Molgulidae; Molgula