Below are a few examples of limpets living on Oregon’s exposed rocky shores. The photos are from northern Oregon unless noted. These are the most easy-to-spot limpets I’ve seen and photographed on the rocky shores I’ve visited—they’re the ones you can find with a light touch without turning rocks or creating disturbances. However, even though they are easy to spot, you might find that identifying some common limpets is tricky. I know I do. For those, I’m not sure my photos clear things up much, but maybe the different perspectives and habitat shots will help a little.
Organization-wise, I loosely follow Lamb and Hanby (2005). I refer to WoRMS for scientific nomenclature and other juicy tidbits; if I use common names, they’re my choice. Experts cover these limpets and many more in the books, field guides, and identification resources listed at the bottom of the page.
Let’s have a look at some limpets!
Lottia digitalis
Diodora aspera
If the shells are encrusted, which they tend to be, they blend in well with the background, making Diodora easy to overlook.
On the beach, drifted shells get tumbled and sand-scoured, which reveals their radiating dark purplish-brown stripes. The bigger shells are something of a beachcombing treasure. Crafty folks make them into Christmas tree ornaments but drifted Diodora shells are at their best on the beach, where they make their play with pebbles and patterns in the sand.
References
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.
Jensen, G. C. 1995. Pacific Coast Crabs and Shrimps. Sea Challengers, Monterey.
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
Biodiversity of the Central Coast’s Molluscs page. Accessed March 25, 2023.
Friends of Netarts Bay WEBS Mollusks page. Accessed March 25, 2023.
Pacific Northwest Shell Club’s Gastropods of the Pacific Northwest page.
Selected Accounts
Cowles, D. (2004). Diodora aspera. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed March 25, 2023.
Cowles, D. (2005, as edited). Lottia digitalis (Rathke, 1833). Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed March 25, 2023.
Unknown. 1983. Lottia digitalis. In: Oregon Estuarine Invertebrates: Rudys’ Illustrated Guide to 140 Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR. Accessed March 25, 2023.
I updated this page on March 25, 2023
theoutershores 