Trapania velox in Carmel, California, USA

January 25, 2006
From: Hans van den Crommenacker

I spotted this tiny nudibranch while diving south Monastery beach in Carmel, California. It looked very different than the usual ones we see in Monterey. I carry an Olympus C5050 camera without a strobe and I take snapshots to ID what we see.

Locality: South Monastery Beach, Carmel, California, USA. Pacific Ocean. Depth: 43 feet. Length: 8-10 mm. 21 January 2006. At the south end of a reef parallel to the beach about 400 yards out from shore. Photographer: Hans Crommenacker

The pictures led me to believe it was a Trapania velox....The northern range of  Trapania velox listed in Behrens' Pacific Coast Nudibranchs is Hazard Canyon, San Luis Obispo County, which is about 100 miles south of Carmel. Searching the local dive reports there was an October 2004 sighting nearby.

My dive buddy, Joel, contacted Clinton Bauder who regularly contributes to the forum. He confirmed seeing it on the same type of sponge in 2004.

The excitement of seeing a new-to-me nudibranch and having a few reasonable pictures prompted me to email David Behrens and Hans Bertsch. Their kind responses confirmed that we saw a Trapania velox. I did not realize that just seeing a nudibranch could generate this much excitement and fun.

Happy diving,


van den Crommenacker, H., 2006 (Jan 25) Trapania velox in Carmel, California, USA. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Hans,
Dave Behrens has included Clinton Bauder's record from Carmel in his recent Eastern Pacific Nudibranchs  (Behrens & Hermosillo, 2005) which I sgould be reviewing soon. It is nice to get a confirmatory report to show it wasn't just a once-off aberration. It is also nice to add another species to the Forum. Although species of Trapania are generally associated with sponges, they don't actually feed on sponges, but instead feed on small stalked animals called entoprocts which are often found growing on particular sponges.
Best wishes,
Bill Rudman

Rudman, W.B., 2006 (Jan 25). Comment on Trapania velox in Carmel, California, USA by Hans van den Crommenacker. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from


Trapania velox