The Ultimate Sea Slug and Nudibranch Compendium for the Pacific Northwest
Pacific Northwest Sea Slug & Nudibranch Database
Research Grade Observations from iNaturalist
Common Nudibranchs
Horned Nudibranch
Horned Nudibranch
Hermissenda crassicornis
Kodiak Island, Alaska to Northern California
Diamondback Tritonia
Diamondback Tritonia
Tritonia festiva
Kachemak Bay, Alaska to Baja California, Mexico
Sea Clown
Sea Clown
Triopha catalinae or Triopha modesta
Southeast Alaska to Gulf of Mexico (T. catalinae) · Alaska to California and trans-Pacific (T. modesta)
Striped Nudibranch
Striped Nudibranch
Armina californica
Gulf of Alaska to Panama
White and Orange Tipped Nudibranch
White and Orange Tipped Nudibranch
Antiopella fusca
Kenai Peninsula, Alaska to central California; also northern Japan
Barnacle-eating Dorid
Barnacle-eating Dorid
Onchidoris bilamellata
Circumboreal: both sides of the North Atlantic, Bering Sea, Alaska south to California
Shag Rug Nudibranch
Shag Rug Nudibranch
Aeolidia papillosa or Aeolidia loui
A. papillosa: Washington northward · A. loui: Oregon to San Diego
White Lined Dirona
White Lined Dirona
Dirona albolineata
Alaska to San Diego, California
Sea Lemons
Sea Lemons
Doris montereyensis, Peltodoris nobilis, or Geitodoris heathi
Kachemak Bay, Alaska to San Diego (all three)
Nanaimo Dorid
Nanaimo Dorid
Acanthodoris nanaimoensis
Baranof Island, Alaska to Santa Barbara, California
Leopard Dorid
Leopard Dorid
Diaulula odonoghuei or Diaulula sandiegensis
D. odonoghuei: Sea of Japan to N. California · D. sandiegensis: BC to Mexico
Hood Nudibranch
Hooded Nudibranch
Melibe leonina
Alaska to Baja California; also Japan
Cockerell's Dorid
Cockerell's Dorid
Limacia cockerelli
Vancouver Island, British Columbia to San Diego, California
Doppelgangers
Modest Clown Dorid
Modest Clown Dorid
Triopha modesta
Alaska to California; also Korea, Japan, and the Russian Far East
Clown Dorid
Clown Dorid
Triopha catalinae
Southeast Alaska to the Gulf of Mexico
Monterey Dorid
Monterey Dorid
Doris montereyensis
Kachemak Bay, Alaska to San Diego, California
Noble Dorid
Noble Dorid
Peltodoris nobilis
Alaska to Baja California
Heath's Dorid
Heath's Dorid
Geitodoris heathi
Alaska to Baja California
Northern Leopard Dorid
Northern Leopard Dorid
Diaulula odonoghuei
Sea of Japan to northern California
San Diego Leopard Dorid
San Diego Dorid
Diaulula sandiegensis
Barkley Sound, British Columbia to Puerto Penasco, Mexico
Shag Rug Nudibranch
Shag Rug Nudibranch
Aeolidia papillosa
North Atlantic and North Pacific; Washington northward on the Pacific coast
Warty Shag Rug Nudibranch
Warty Shag Rug Nudibranch
Aeolidia loui
Cape Arago, Oregon to San Diego, California
Cockerell's Dorid
Cockerell's Dorid
Limacia cockerelli
Vancouver Island, British Columbia to San Diego, California
McDonald's Dorid
McDonald's Dorid
Limacia mcdonaldi
Salt Point, Sonoma County to Bahia de los Angeles, Baja California
Horned Nudibranch
Horned Nudibranch
Hermissenda crassicornis
Alaska to Northern California
Opalescent Nudibranch
Opalescent Nudibranch
Hermissenda opalescens
Sea of Cortez to Northern California