Below is a selection of chitons I’ve been lucky to find and photograph in northern Oregon’s exposed rocky intertidal habitats. They’re the most easy-to-spot chitons—the ones you can find with a light touch without turning rocks or creating disturbances. However, easy-to-spot doesn’t translate to easy identification, at least not for me. Experts cover these and many more chitons in the guides and online resources at the bottom of this page. Organization and common names are my choices; unless noted, the photos are from northern Oregon.

Here’s to the chitons!

I’m pretty confident these are lined chitons Tonicella lineata. They are relatively abundant in the mid and low intertidal zones, something I’m grateful for because each one is pure living beauty.

Katharina tunicata, Katy chiton
Katies don’t try too hard to hide. (But sometimes they’ll nose into a shadow.) Look for them on mid and low intertidal rocks, where you won’t confuse them with any other chiton.

The gallery provides just a glimpse of variation among the easy-to-spot Mopalia. (I’m not entirely confident in my selections, but I think they are all Mopalia.)

It’s not too uncommon to find drifted valves washed up on the beach.


Gotshall, D. W. 2005. Guide to Marine Invertebrates, Alaska to Baja California. 2nd Edition (Revised). Shoreline Press.

Harbo, R. M. 2011. Whelks to Whales: Coastal Marine Life of the Pacific Northwest. 2nd ed. Harbour Publishing Co.

Kozloff, E. N. 1993. Seashore Life of the Northern Pacific Coast. 3rd ed. University of Washington Press.

Lamb, A. and B. P. Hanby. 2005. Marine Life of the Pacific Northwest. Harbour Publishing.

Sept. J. D. 2019. The New Beachcomber’s Guide to the Pacific Northwest. Harbour Publishing.

Online Resources

Pacific Northwest Shell Club’s Chiton page. Accessed April 25, 2023.

Aaron Baldwin’s Illustrated Keys to the Chitons (Polyplacophora). Accessed April 25, 2023.

Biodiversity of the Central Coast’s Molluscs page. Accessed April 25, 2023.

Common Sea Life of Southeastern Alaska: A field guide by Aaron Baldwin & Paul Norwood. Accessed April 25, 2023.

Friends of Netarts Bay WEBS Mollusks page. Accessed April 25, 2023.

Cowles, D. (2005). Tonicella lineata (Wood, 1815). Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed April 25, 2023.

Lunsford, R. (2002). Katharina tunicata. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed April 25, 2023.

I updated this page on April 27, 2023.