Mini macaroni?

  

These tubular shells look a little bit like macaroni, don't they?  I had noticed examples of this family in shell books over the years, but I hadn't seen a live animal until this past summer. 

While examining some sediment samples, Maddy spotted these tiny snails crawling around among the sand grains.  They reach a maximum length of 2.5 mm (⅛ inch) — even smaller than a grain of rice.

 

 

Meet Caecum orcutti!  This species has been documented as far north as Pacific Grove, but this appears to be the first record north of San Francisco. 

Although the shells themselves are interesting, the live animals are even more intriguing.  Eric captured a few of them in a short video clip (see below).  They're quite speedy!  Note the long antennae, the short foot, and the circular operculum ("trap door") that seals the opening of the aperture (visible at ~0:44 seconds).  [If you can't see the video in your e-mail message, click on the title of this post to go to the NHBH web page.]

 

 

Many thanks to Maddy and Eric for finding and documenting these snails, and to Bret Raines (Natural History Museum of Los Angeles County) for confirming the identification.