Opisthobranch of the Week is Okenia angelensis

Image courtesy of Merry Passage and Phil Garner
Photo by Merry Passage
Divesite: Rock Pile, Santa Monica Bay, Calif

Image courtesy of Merry Passage

Okenia angelensis Lance, 1966

Jim Lance named this species after Bahia de Los Angeles where the type specimens were collected. Other specimens were collected from San Francisco Bay, Monterey Bay, Santa Barbara Yacht Harbor, and Mission Bay, San Diego. Although having a very wide distribution, San Francisco to Chile, South America, it is a rather uncommon species. Merry's photo here shows all the the key features: the cylindrical processes on the notum, the yellow, white and brown flecks and patches, and rhinophores with just 2 small lamellae. If I could wager a guess, I would say this specimen is crawling on its prey, a small arborescent bryozoan.

Nice find Merry.

Dave Behrens
Sammamish, WA 98074
Feb., 2018
Send Dave email at davidwbehrens@gmail.com

"...Last Sept., I found an extremely small Okenia angelensis on a rock-pile in Santa Monica Bay . On 12/18/2017, I got incredibly lucky in finding a slightly larger one on the Hyperion 1-mile outfall pipe. The outfall pipe provides a unique habitat, elevated above the sea floor and surrounded by nothing except sandy plain. The pipe is covered with stunning gray moon sponges, tiny anemones, hydroids, bryozoans and mussels. It's an apparent oasis for Trapania velox, Dendronotus venustus, Doto kya, Doto form A, Trinchesia albocrusta, and a handful of other common, local species..."

Merry Passage worked as a genetics research scientist at Harbor UCLA for three decades. After retiring she has used her degrees from Arizona State University and laboratory experience as an aid to scuba diving. She spends countless hours researching many of the animals we find underwater. Her home office is filled with binders and identification books from algae to whales.

Send Merry email at pacificcoast101@yahoo.com

From left to right, Terry Gosliner, Angel Valdes, Dave Behrens La Jolla, Calif.

Send Dave email at davidwbehrens@gmail.com