Saturday, April 2, 2016

Two mysteries solved

This is a tale of two mysteries solved.

This year, Eric and I have found several shell fragments of a mystery snail washed up on Salmon Creek Beach.  We have encountered five of them (one just today!), but here are the four that we had found by late March (in order of discovery, from left to right they range from ~2-3.5 cm long):


The first three pieces were fairly incomplete, and didn't provide enough clues to identify the snail.  However, the fourth piece was more substantial.  Here are two different views:




Finding this larger piece gave me hope, and I started looking through various identification guides for a match.  Unfortunately, I didn't have any luck identifying this snail using that method.  (Frustrating!)

Then, one day, I was browsing Jim Watanabe's website for a different reason, and I happened to scroll down to the bottom and realized I was looking at a beautiful picture of our mystery snail!  

Meet Carpenter's Turrid (Megasurcula carpenteriana).  You can see Jim Watanabe's picture of a live animal here.  It appears that Bodega Bay is the northern limit for this subtidal snail.

Then came the second epiphany.  Years ago, Jim Carlton brought me a broken shell that one of his students had found on a beach near Bodega Head.  None of us knew what it was at the time.  For years I have been keeping that shell in the back of my mind, hoping to identify it some day.


Just after I figured out that our shell fragments were Carpenter's Turrids, I realized that it was very likely that Jim's student's shell was also a Carpenter's Turrid.  Whew!  It's fun to have mysteries, but it's also nice to solve them.

P.S.  In 2014, I shared pictures of some wonderful snail larvae (veligers) that we thought might belong to a turrid snail.  As a group, turrids are predominantly southern, but now we're wondering if the veligers with the pretty orange spots could possibly be Carpenter's Turrids?  As is often the case, when one (or two) mysteries are solved, others appear!

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