Biodiversity of the Central Coast
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Molluscs

This diverse group includes chitons; clams, mussels, scallops, and other bivalves; sea snails and limpets; octopuses and squid; and nudibranchs. The basic mollusc body form has a shell, though in some molluscs the shell is reduced or internalized, or has been lost altogether. Other general traits common to molluscs include gills, a muscular foot which is often used to attach to substrates, and a rough tongue-like structure called a radula. Despite these commonalities, molluscs vary widely in body form and size. Click here for more information on molluscs.

Chitons

Chitons belong to Class Polyplacophora (poly = many, placo = tablet, phoros = bearing); they have eight overlapping calcareous shell plates that are partially or completely embedded in tough girdle tissue. These animals are very slow-moving.
Black katy chiton (Katharina tunicata)

Black katy chiton (Katharina tunicata)

Mossy chiton (Mopalia muscosa)

Mossy chiton (Mopalia muscosa)

Giant pacific chiton (Cryptochiton stelleri)

Giant pacific chiton (Cryptochiton stelleri)

Lined chiton (Tonicella lineata)

Lined chiton (Tonicella lineata)

White-line chiton (Tonicella insignis)

White-line chiton (Tonicella insignis)

Hind's mopalia (Mopalia hindsii)

Hind's mopalia
(Mopalia hindsii)

Veiled chiton (Placiphorella velata)

Veiled chiton (Placiphorella velata)


Bivalves

Bivalves have two hinged shell valves. Many bivalve species are harvested for food.
California mussel (Mytilus californianus)

California mussel
(Mytilus californianus)

Blue mussel (Mytilus edulis, Mytilus trossulus, Mytilus galloprovincialis)

Blue mussel (Mytilus spp.)

Butter clam (Saxidomus gigantea)

Butter clam (Saxidomus gigantea)

Pacific littleneck clam (Leukoma staminea)

Pacific littleneck clam (Leukoma staminea)

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Baltic macoma (Macoma balthica)

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Bent-nose macoma
​
(Macoma nasuta)

Nuttall's cockle (Clinocardium nuttallii)

Nuttall's cockle (Clinocardium nuttallii)

Green false-jingle (Pododesmus macrochisma)

Green false-jingle (Pododesmus macrochisma)

Threaded pandora (Pandora filosa)

Threaded pandora (Pandora filosa)

Fat gaper (Tresus capax)

Fat gaper
(Tresus capax)

Pacific gaper (Tresus nuttallii)

Pacific gaper (Tresus nuttallii)

Pacific razor-clam (Siliqua patula)

Pacific razor-clam (Siliqua patula)

Western ringed lucine (Lucinoma annulatum)

Western ringed lucine (Lucinoma annulatum)

California sunsetclam (Gari californica)

California sunsetclam
​
(Gari californica)

Rock entodesma (Entodesma navicula)

Rock entodesma (Entodesma navicula)

Smooth pink scallop (Chlamys rubida)

Smooth pink scallop (Chlamys rubida)

Spiny pink scallop (Chlamys hastata)

Spiny pink scallop
(Chlamys hastata)

Rock scallop (Crassodoma gigantea)

Rock scallop (Crassodoma gigantea)

Weathervane scallop (Patinopecten caurinus)

Weathervane scallop (Patinopecten caurinus)

Purple varnish clam (Nuttallia obscurata)

Purple varnish clam (Nuttallia obscurata)

Japanese littleneck clam (Venerupis philippinarum)

Japanese littleneck clam (Venerupis philippinarum)

White-sand macoma ​(Macoma secta)

White-sand macoma
​
(Macoma secta)

Expanded macoma (Macoma expansa)

Expanded macoma (Macoma expansa)

Ample roughmya (Panomya ampla)

Ample roughmya (Panomya ampla)

Eastern soft-shell clam (Mya arenaria)

Eastern soft-shell clam (Mya arenaria)

Western bittersweet (Glycymeris septentrionalis)

Western bittersweet (Glycymeris septentrionalis)

Hooked surfclam (Simomactra falcata)

Hooked surfclam (Simomactra falcata)

Plain tellin (Tellina modesta)

Plain tellin
​
(Tellina modesta)

Bodegin tellin (Tellina bodegensis)

Bodegin tellin (Tellina bodegensis)

Kennerley's venus (Humilaria kennerleyi)

Kennerley's venus (Humilaria kennerleyi)


Snails

Grouped here are the sea snails and other similar univalves (single-shelled gastropods) that have coiled or curved shells. 
Northern abalone (Haliotis kamtschatkana)

Northern abalone
(Haliotis kamtschatkana)

Purple olive (Olivella biplicata)

Purple olive
(Olivella biplicata)

Lewis's moonsnail (Euspira lewisii)

Lewis's moonsnail
(Euspira lewisii)

Black turban (Tegula funebralis)

Black turban
(Tegula funebralis)

Dusky turban (Tegula pulligo)

Dusky turban
(Tegula pulligo)

Red turban  (Pomaulax gibberosa)

Red turban 
(Pomaulax gibberosa)

Picture

Blue topsnail (Calliostoma ligatum)

Northern striped dogwinkle (Nucella ostrina)

Northern striped dogwinkle
(Nucella ostrina)

Wrinkled amphissa (Amphissa columbiana)

Wrinkled amphissa (Amphissa columbiana)

Dire whelk (Lirabuccinum dirum)

Dire whelk (Lirabuccinum dirum)

Purple-ringed topsnail (Calliostoma annulatum)

Purple-ringed topsnail (Calliostoma annulatum)

Leafy hornmouth (Ceratostoma foliatum)

Leafy hornmouth (​Ceratostoma foliatum)

Frilled dogwinkle (Nucella lamillosa)

Frilled dogwinkle (Nucella lamillosa)

Checkered periwinkle (Littorina scutulata)

Checkered periwinkle
​
(Littorina scutulata)

Sitka periwinkle (Littorina sitkana)

Sitka periwinkle (Littorina sitkana)

Black periwinkle (Littorina plena)

Black periwinkle (Littorina plena)

Hooked slippernsail (Crepidula adunca)

Hooked slippersail (Crepidula adunca​)

Oregon triton (Fusitriton oregonensis)

Oregon triton (Fusitriton oregonensis)


Limpets

Grouped here are the true limpets, keyhole limpets, and similar cone-shaped univalves (single-shelled gastropods).
Ribbed limpet (Lottia digitalis)

Ribbed limpet (Lottia digitalis)

Mask limpet   (Tectura persona)

Mask limpet  
(Tectura persona)

Whitecap limpet (Acmaea mitra)

Whitecap limpet (Acmaea mitra)

Unstable limpet (Lottia instabilison)

Unstable limpet (Lottia instabilison)

Rough keyhole limpet (Diodora aspera)

Rough keyhole limpet (Diodora aspera)

Two-spot keyhole limpet (Fissurellidea bimaculata)

Two-spot keyhole limpet (Fissurellidea bimaculata)


Nudibranchs

Also known as sea slugs, these gastropods have lost the typical mollusc shell. There are various nudibranch body forms: some are relatively smooth, flat, and oval-shaped, while others are more elongated and have elaborately-branched or frilled structures projecting off their backs.
White-lined dirona (Dirona albolineata)

White-lined dirona (Dirona albolineata)

Monterey sea lemon (Doris montereyensis)

Monterey sea lemon (Doris montereyensis)

Hooded nudibranch  (Melibe leonina)

Hooded nudibranch 
(Melibe leonina)

Opalescent nudibranch (Hermissenda crassicornis)

Opalescent nudibranch (Hermissenda crassicornis)

Leopard dorid (Diaulula sandiegensis)

Leopard dorid (Diaulula sandiegensis)

Barnacle nudibranch (Onchidoris bilamellata)

Barnacle nudibranch (Onchidoris bilamellata)

Bushy-backed nudibranch (Dendronotus frondosus)

Bushy-backed nudibranch (Dendronotus venustus)

Red sponge nudibranch (Rostanga pulchra)

Red sponge nudibranch
(Rostanga pulchra)

Clown nudibranch (Triopha catalinae)

Clown nudibranch (Triopha catalinae)

Giant nudibranch (Dendronotus iris)

Giant nudibranch (Dendronotus iris)

Picture

White-and-orange-tipped nudibranch (Janolus fuscus)

Giant white dorid (Doris odhneri)

Giant white dorid (Doris odhneri)

Orange peel nudibranch (Tochuina tetraquetra)

Orange peel nudibranch (Tochuina tetraquetra)

Heath's dorid (Geitodoris heathi)

Heath's dorid (Geitodoris heathi)

Cockerell's nudibranch (Limacia cockerelli)

Cockerell's nudibranch (Limacia cockerelli)

Variable dendronotid (Dendronotus albus)

Variable dendronotid (Dendronotus albus)

Red-gilled nudibranch (Flabellina verrucosa)

Red-gilled nudibranch
​
(Flabellina verrucosa)

Three-lined aeolid (Flabellina trilineata)

Three-lined aeolid (Flabellina trilineata)

Nanaimo dorid (Acanthodoris nanaimoensis)

Nanaimo dorid (Acanthodoris nanaimoensis)

Striped nudibranch (Armina californica)

Striped nudibranch
​
(Armina californica)

Yellow-rimmed nudibranch (Cadlina luteomarginata)

Yellow-rimmed nudibranch (Cadlina luteomarginata)

Shag-rug nudibranch (Aeolidia papillosa)

Shag-rug nudibranch
​
(Aeolidia papillosa)


Other Opisthobranchs

Nudibranchs belong to a subclass of gastropods known as Opisthobranchia. This group includes bubble shells, pteropods, sea hares, and more. The majority of opisthobranchs have a reduced shell, internalized shell, or no shell at all. Listed here are the other opisthobranchs, which tend to be recognized less than nudibranchs.
Sea butterfly (Corolla spectabilis)

Sea butterfly (Corolla spectabilis)


Octopuses and Squid

Squid and octopuses, as well as cuttlefish and nautlilus, are cephalopods (cephalo = relating to the head or skull, pod = foot). These animals have diverse body forms. Squid have an internalized and reduced shell in the form of a chitinous pen, while octopuses have lost the typical molluscan shell altogether.
Giant Pacific octopus (Enteroctopus dofleini)

Giant Pacific octopus (Enteroctopus dofleini)

Pacific red octopus (Octopus rubescens)

Pacific red octopus (Octopus rubescens)

Opalescent squid (Doryteuthis opalescens)

Opalescent squid
(Doryteuthis opalescens)

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