Gulf Wedge Clam from the Gulf of Mexico!

Are you interested in looking for non-native marine species?

Then this species might just be the thing for you! The brackish water bivalve mollusc Gulf Wedge Clam (Rangia cuneata) is considered to native in Gulf of Mexico, where it lives in estuaries, lagoons and coastal lakes.

It appears to prefer fine sand habitat, however in Europe they have been recorded mostly in silt, mud and clay. Specimens of the Gulf Wedge Clam were first found in August 2015 at Hubbert’s Bridge and Wyberton High Bridge (canals which drain into the Haven at Boston near The Wash, Lincolnshire UK).

Identification Features (sourced from Willing, 2016):

  • Size (length): Adults up to 60mm
  • Outer Shell:
    • Thick, heavy, moderately tumid shell
    • Obliquely oval, umbos set off-centre & curl towards anterior end of shell
    • Relatively smooth, with regular growth lines on shell surface
    • Ligament not visible externally
    • Light brown to grey in colour
    • Dull matt, slightly rough periostracum
  • Inner shell:
    • White with glossy areas
    • Dark brown internal ligament in deep triangular pit
    • Lateral teeth show very fine serrations
    • Pallial sinus clearly seen as infolding line

Please report any sightings of this species with a photograph if possible, location details, and any other details to alertnonnative@ceh.ac.uk -  Emma Holden, Environment Agency.

For more information on the known UK population of the Gulf Wedge Clam please contact emma.holden@environment-agency.gov.uk

Thank you.