This is one of my favorite local marine snails, the Tinted Wentletrap (Epitonium tinctum). It's ~1.5 cm tall, slender, with tight whorls and well defined axial ribs (or varices). The ribs appear to spiral around the shell towards the apex, hence the name wentletrap, originally a Dutch term for a spiral staircase.
Tinted Wentletraps are specialized carnivores, feeding on sea anemones. On Bodega Head, they can be found nestled among Aggregating Anemones (Anthopleura elegantissima) — see below. This may be a little challenging, but how many wentletraps can you find in the photo below? (Note that some of the snails are partially buried in the sand and a little out of focus.)
There are 5 wentletraps. Along with the one in full view, there are four others:
When reading about this species, I learned that their egg capsules are coated with sand. After looking at the photo above I think there might be some egg capsules just to the left of the lower right snail (see next photo). They are larger and appear more rounded than typical sand grains at this site. (I'll explore further on another day and will report back.)
Although not the same species of wentletrap, I've always liked this drawing of wentletraps and their anemone prey from the 4th and 5th editions of Between Pacific Tides.
Some species of wentletraps pierce the columns or sides of anemones, but the Tinted Wentletrap attacks the anemone's tentacles! It's been suggested that the snails produce a toxin that anesthetizes the tentacles so they can't retract.