TUNICATA : APLOUSOBRANCHIA : Polycitoridae | SEA SQUIRTS |
![]() |
Archidistoma aggregatum |
Description: This inconspicuous colonial ascidian consists of small globular heads with short stalks, grouped together in a patch arising from a thin sheet of shared test. It is almost colourless, with a brown or grey overall hue and no obvious markings. Each head is about 5mm in diameter and consists of about 10 zooids arranged around a common central exhalent opening.
Habitat: Found normally in sand-scoured sites with significant tidal streams.
Distribution: Found from Plymouth and Salcombe in southern England north to the Irish Sea and North Channel. Probably under-recorded due to its inconspicuous appearance and small size.
Similar Species: Compare with Synoicum incrustatum and Polyclinum aurantium. These are both bigger colonies than Archidistoma aggregatum.
Key Identification Features:
Distribution Map: NBN map : National Biodiversity Network mapping facility, data for UK.
WoRMS: Species record : World Register of Marine Species.
iNaturalist: Species account : iNaturalist World Species Observations database
![]() |
Picton, B.E. & Morrow, C.C. (2016). Archidistoma aggregatum Garstang, 1891. [In] Encyclopedia of Marine Life of Britain and Ireland. https://www.habitas.org.uk/marinelife/species.asp?item=ZD230 Accessed on 2023-11-29 |
Copyright © National Museums NI, 2002-2023 |