Barrel bubble

  

Caroline spotted this intriguing gastropod in Tomales Bay on 7 August 2024.  It's a species we hadn't seen before, so Eric took some documentary photos and videos (see the wonderful video below!).

Although we need to confirm with experts, we think this is a barrel-bubble snail, Acteocina inculta.  This is generally described as a southern species, from either Monterey Bay or Morro Bay southward.  There are a couple of museum records for San Francisco, but it's possible this is the first record for Marin County — we'll need to do more research on museum records.

Acteocina inculta is a small head-shield slug (this individual's shell was a little over 3 mm long).  Note the head-shield in front of the shell — and that the back edge of the head-shield is split into two rounded lobes.

Eric captured some very nice video footage of this hard-to-find species, so here you go!  

[If you can't see the video player in the e-mail message, click on the title of post above to go directly to the NHBH website.]

With many thanks to Caroline for her sharp eyes and hard work!