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. manhattensis the testis overlies the surface of the ovary and there are multiple testis follicles with separate male gonopores directed randomly.

Habitat: Hard substrata (e.g. bedrock, boulder or shells) including artificial substrata, down to around 90 m. Mostly recorded in harbours and marinas.

Distribution: A non-native that is now widespread around Britain and Ireland, although there are currently few records from the west coast of Ireland.

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

Key Identification Features:

• Solitary ascidian with stout spherical body and long siphons.
• Multiple testis follicles with separate male gonopores directed randomly.

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

iNaturalist: Molgula manhattensis at iNaturalist World Species Observations database.

GBIF data for Molgula manhattensis

WoRMS: Molgula manhattensis at World Register of Marine Species. Accepted name: Molgula manhattensis (De Kay, 1843). AphiaID: 103788.

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