Field Guide For Hopkins Marine Station’s Common Intertidal Invertebrates Prepared by Kimberly Heiman 4/9/01 Anthopleura sola 15cm diam. Anthopleura xanthogrammica, Solitary anemone, Oral disk has 18cm diam dark strips. Shells attached. Giant green anemone, green oral Mid- intertidal disk, no shells attached, found submerged Mid, Low-intertidal exposed Anthopleura elegantissma, 5cm Corynactis californica ~10 mm diam diam Strawberry anemone, red orange, pink Aggregating anemone, mats caused with white tentacles. by clone division, shells attached. Low-intertidal Mid-intertidal Phragmatopoma californica ~10mm diam opening. Tube Spirorbids ~3mm across worm, tubes made of shell Tube worm, small white tube coiled fragments or sand, often on one time. Mid-intertidal lower parts of boulders. High-intertidal, protected Lottia limatula ~25mm Lottia digitalis ~25mm Limpet, egg-shaped, file-like Limpet, worn-looking, oval shaped, ribs, does not conform to rocks. apex anterior quarter High, Mid-intertidal High-intertidal ‘Collisella’ scabra 25mm Lottia pelta ~30mm Limpet, conforms to rocks, Limpet, dark, medium-high anterior and posterior slopes profile, apex anterior third, ribed straight. High-intertidal High, Mid-intertidal Lottia asmi ~10mm Limpet, high profile, dark, apex Lottia gigantea ~60mm anterior 3rd, smooth cone Owl limpet, low profile, apex associated with Tegula. anterior, broad ribs, egg shaped Mid-interidal High-intertidal, exposed Acmaea mitra ~30mm Fissurella volcano ~30mm Limpet, high profile, apex Keyhole limpet, pink-red in subcentral, straight slopes, color, associated with coralline light. Mid-intertidal algae. Mid, Low-intertidal Littorina keenae Littorina scutulata ~10mm diam ~10mm diam Periwinkle, wider less elongated shell, Periwinkle, elongated white strip on inner lip. Highest-intertidal Highest-intertidal Tegula funebralis Calliostoma ligatum ~22mm diam ~20mm diam Topsnail, conical chocolate brown Black turban snail, Dark shell shell w tan spiral ridges. Blue interior, with light apex, black foot. orange foot. Mid, Low- intertidal High, Mid-intertidal Tegula brunnea Crepidula adunca ~10mm ~28mm diam Hooked slipper snail, associated Brown turban snail. Shell with other snails, anterior hook often overgrown with red alga, Mid, Low-intertidal rust-orange foot. Low-intertidal Acanthina punctulata ~30mm Ocenebra circumtexta 17mm high high, Spotted unicorn whelk, Black Circled rock whelk, outer lip bumpy dashes on surface, smooth lip with due to connection with outer ridges, a tooth. black marks in concentrated bands. Mid-intertidal, protected. Mid-intertidal, protected Nucella ostrina ~35mm high Emarginate Dogwinkle, Thick purple Sepulorbis squamigerus lip, associated with barnacle & ~10mm diam openings mussel beds, shell color variable Fixed snail, furrowed and ridged (orange, dark stripped) tube. Mid, Low-intertidal protected Mid-intertidal, exposed (variable) Lepidochitona hartwegii Nuttallina californica 40mm 28mm long, Chiton, smooth wide long, Chiton, Long narrow, green plates, orange foot moderately hairy dark brown foot. found under Pelvetia. High-intertidal High-intertidal Mopalia muscosa ~55mm Haliotis cracherodii ~18cm long. Chiton, Dark broad Black abalone, dark shell, black plates, dark hairy foot mantal extends over shell Mid-intertidal, Exposed Mid-intertidal~subtidal Pollicipes polymerus 6cm long. Mytilus californianus 10cm long Gooseneck barnacle, fleshystalk, Mussel, blue-brown, with strong ribs articulated shell w two main plates Mid-intertidal, exposed on each side. Mid-intertidal exposed Chthamalus spp. 8mm diam Balanus glandula, 15mm diam Acorn barnacle, gray with Acorn barnacle, tall white, ridged, darker gray beak. hooked plates. High-intertidal High-intertidal Tetraclita rubescens ~30mm diam Pagurus samuelis Barnacle, red, ridged, tan legs Carapace 18mm long Hermit crab. Mid, Low-intertidal, exposed Blue bands on legs. Tidal pools Pagurus hemphilli Strongylocentus purpuratus Carapace 18mm long, Hermit crab, 60mm diam red legs. Tide pools Purple sea urchin. Low-intertidal Asterina miniata ~5cm Pisaster ochraceus ~12cm Bat Star, webbed arms, color Ochre Starfish, web-like ridges on surface, variants include: yellow, orange, hard white spins, color variants include: red, and tan. orange, purple, and brown. Low-intertidal~ subtidal Low-intertidal ~subtidal exposed.