Common Southern California Rocky Intertidal

ANNELIDS Scientific Name Common Name Abbreviation Spirorbis sp. Coiled tube worm SPSP Description: A very small (less than 5 mm long) worm that makes a coiled white tube. Chaetopterus variopedatus Parchment tube worm CHVA Description: A large (up to 400 mm long) worm that creates a paper-like tube around itself for protection. Phragmatopoma californica Sandy tube worm PHCA Description: A solitary worm that builds a sandy tube to live in; They often clump together to form large “sand castles” CNIDARIANS (anemones & corals) Scientific Name Common Name Abbreviation Anthopleura elegantissima Aggregate anemone ANEL Description: Smaller (usually less than 100 mm across), colonial .; often cover their bodies with pebbles and shell fragments. Anthopleura xanthogrammica Green anemone ANXA Description: Large (up to 250 mm across), single animals; disk can be white to green in colour. Corynactis californica Strawberry anemone COCL Description: Small (less than 50 mm across), single animals, although they may be found in clumps; disk is often pink or red in colour. Balanophyllia elegans Orange cup coral BAEL Description: Very small (10 to 15 mm across), single animals, although they may be found in clumps; orange or yellowish-orange in colour. CRUSTACEANS BARNACLES: Nonmoving as adults, may be roughly volcano shaped, or hoof shaped and on stalks. Scientific Name Common Name Abbreviation Balanus glandula White acorn barnacle BAGL Description: B. glandula: bigger than C. fissus, up to 15 mm in diameter and 10 mm high; white to grey in colour; cone shaped, with a diamond-shaped operculum; and deeply ridged plates. Megabalanus californicus Red & white barnacle MECA Description: Large, up to 50 mm in diameter and 30 mm in height;plates are red with white lines; finely grooved; has distinct white sections between striped plates. Chthamalus fissus Brown barnacle CHFI Description: Small, up to 8 mm in diameter and 5 mm high; brown-greyish; smooth with oval operculum. Tetraclita squamosa Thatched barnacle TESQ Description: Diameter up to 40 mm; wall consisting of 4 obvious plates that are deeply grooved and reddish-grey. Pollicipes polymerus Goosenecked barnacle POPO Description: A stalked barnacle, with 2 large and many small lumpy plates on each side.

CRABS: Usually oval or triangular in shape; flattened top to bottom; have 2 large pinchers and 8 legs; antennae generally between the eyes. Scientific Name Common Name Abbreviation Pachygrapsus crassipes Striped shore crab PACR Description: Carapace is almost rectangular and green to purple, with lighter coloured stripes; probably the most common tidepool crab; up to 40 mm wide. Hemigrapsus nudus Purple shore crab HENU Description: Carapace is almost rectangular and red to purple in colour, with no stripes; up to 40 mm wide. Cancer antennarius Common rock crab CAAN Description: Carapace is very oval; the top of the carapace is brownish, while the bottom and legs are covered with small reddish or purple spots; can get very large.

Cancer productus Red rock crab CAPR Description: Carapace is very oval; the top of the carapace is generally red or reddish-purple; adults smaller than C. antennarius. Pugettia producta Northern crab PUPR Description: Adults grow up to 80 mm, not including legs; colour ranges from light yellowish-brown to dark olive-brown, carapace has 2 spines on each side. Petrolisthes cinctipes Flat porcelain crab PECI Description: Small crabs, usually less than 15 mm, with antennae outside the eyes; claws are long, relative to the body. Pagurus samuelis Blue-clawed hermit crab PASA Description: Commonly found in tidepools; claws and legs have blue bands near the ends; use discarded snail shells for protection.

LOBSTER and SHRIMP: Long in shape, flattened on the sides, with multiple legs and an obvious tail. Scientific Name Common Name Abbreviation Panulirus interruptus California PAIN Description: Adults grow up to 1000 mm in length; have long, spiny antennae, but no large claws; they are generally greenish brown as juveniles, turning reddish brown as adults. Lysmata californica Striped shrimp LYCA Description: Adults grow up to 50 mm in length; clear to white with lengthwise reddish stripes. Heptacarpus sitchensis Green shrimp HESI Description: Adults grow up to 25 mm in length; green in colour, with reddish vertical stripes near the head.

ISOPODS: Long in shape, flattened top to bottom, with multiple legs and a tail. Ligia occidentalis Western sea roach LIOC Description: Roach-like crustaceans up to 50 mm long that are commonly found above the high water mark.

MOLLUSCS GASTROPOD MOLLUSCS: Molluscs with a single shell that often, but not always spirals outward as the grows. Scientific Name Common Name Abbreviation Haliotis cracherodii Black abalone HACR Description: Abalone have a large, flat shell with a curved row of holes along one side. The black abalone has a smooth, black shell. Fissurella volcano Volcano limpet FIVO Description: A tent-shaped shell with no spiral. Fissurella is small (to 30 mm) with an oval shell that has a small opening at the top. Colour varies, but they often have radiating stripes. Megathura crenulata Giant keyhole limpet MECR Description: The largest Southern California limpet (to 120 mm); mantle may be black or tan with brown markings; foot is generally orange; shell is oval, with a .5 to 1 mm central hole and radiating ribs. Lottia gigantea Giant owl limpet LOGI Description: A large limpet (up to 70 mm), oval in shape; generally brown with white markings. Collisella digitalis Finger limpet CODI Description: A small limpet (up to 25 mm), oval in shape with radiating ridges; has a smooth shell edge; generally brown with white markings. Collisella scabra Rough limpet COSC Description: A small limpet (up to 25 mm), has strongly radiating ridges and an irregular shell edge. black or grey to dirty white in colour. Collisella limatula File limpet COLI Description: A small limpet (up to 20 mm), with a very low oval shell that is smooth or has fine ridges; tan to grey in colour. Crepidula onyx Onyx slipper shell CRON Description: A small cone-shaped shell (up to 50 mm), smooth and dirty white outside with a small shelf inside that can be seen on dead shells. Serpulorbis squamigerus Tube snail SESQ Description: This stationary snail is generally found attached to rocks; the shell coils initially, but then becomes a long, squiggly tube. Olivella biplicata Purple olive shell OLBI Description: A small (up to 25 mm long) oval shaped spiral shell; light grey to dark purple in color; the shell opening is a long slit. Tegula funebralis Black turban snail TEFU Description: A medium sized (up to 30 mm) smooth, spiraled shell; no umbilicus; black in colour, but the black often wears off at the top; found in the upper intertidal zone. Tegula eiseni Banded turban snail TEEI Description: A small sized (up to 25 mm) snail with light, beaded ridges running along the spiral of the shell; open umbilicus; light to medium in colour, often patterned; found in the middle to low intertidal zone. Tegula aureotincta Gilded turban snail TEAU Description: A medium sized (up to 40 mm) snail with heavy ridges running along the spiral of the shell; open umbilicus coloured yellow or orange; grey or greenish grey in colour; found in the low intertidal zone. Norrisia norrisi Brown turban snail NONO Description: A medium sized (up to 50 mm) snail with a smooth, flat shell; brown in colour, with a bright green umbilicus and bright red on its foot. Littorina scutulata Checkered periwinkle LISC Description: A small (up to 10 mm long) snail with rounded, tapered shell; usually brownish with pale markings. Lithopoma undosa Wavy top turban LIUN Description: A large (up to 130 mm in diameter, 100 mm high) snail with a heavy, wavy edge; the shell is usually white, but often covered by stringy, brown membrane. Ceratostoma nuttalli Nuttall’s hornmouth CENU Description: A medium sized (up to 50 mm long) shell with a large opening; there is a large, tooth-like spike near the bottom of the opening, and it has obvious ridges running across the spiral; it is often banded brown and white in colour Pteropurpura festiva Festive murex PTFE Description: A small sized (up to 20 mm long) shell with a large opening; it has obvious ridges running across the spiral; it is often light brown with fine, dark brown lines. Ocenebra poulsoni Poulson’s rock shell OCPO Description: A medium sized (up to 50 mm long) shell with a large opening and a long, tapering spire; it may have white ridges running across the spiraled is otherwise a medium brown with white accents. Maxwellia gemma Gem murex MAGE Description: A small sized (up to 30 mm long) shell with a small opening near the middle, a short spire, and a long, grooved tail; the shell is white with brown bands. Acanthina spirata Angular unicorn ACSP Description: A small sized (up to 25 mm long) shell with a very large opening and a short spire; there is a sharp spine located along the lower lip of the opening; it is greyish-green with light bands. Acanthina emarginata Emarginate dogwinkle ACEM Description: A small sized (up to 25 mm long) shell with a large opening and a short spire; they are grey to brown to orange with white bands. Kelletia kelleti Kellet’s whelk KEKE Description: A large sized (up to 150 mm long) snail with a heavy, whorled shell that has a long, tapered spire; the shells are naturally tan to white, but often have a layer of green algae covering the shell. Conus californicus California cone shell COCA Description: A small sized (up to 25 mm long) brown snail who’s shell has a long slit opening and a short spire; it is found in the low intertidal.

OTHER MOLLUSCS OPISTHOBRANCHS: Molluscs with no obvious shell; sea slugs. Scientific Name Common Name Abbreviation californica APCA Description: A large (up to 450 mm long) sea slug that secretes a purple ink when disturbed; they have 2 sets of oral tentacles, which give the appearance of ears; they are greyish green to red to brown with brown spots. Sea cow APVA Description: A very large (up to 900 mm long) sea slug that is usually jet black in colour; they have 2 sets of oral tentacles, which give the appearance of ears. Hermissenda crassicornis Opalescent sea slug HECR Description: A small (up to 50 mm long) sea slug with a bluish-grey body and white tipped orange projections down its back; it has a large red and yellow diamond shaped mark between its rhinopores. Navanax inermis Striped sea slug NAIN Description: A medium to large (up to 300 mm long) sea slug that has a black to grey body with 2 lines of blue spots and scattered yellow spots; they are fierce predators. BIVALVES: Molluscs with two paired shells that hinge together. Scientific Name Common Name Abbreviation Mytilus sp. Mussel MYSP Description: A medium to large (normally 30 to 150 mm long) bivalve with bluish- black ribbed shells; they generally occur in large groups, clinging to rocks and other surfaces by sticky threads; they are the most common bivalve on rocky shores. CEPHALOPODS: Molluscs with no external shell; they have multiple legs; they use a water jet to swim. Scientific Name Common Name Abbreviation Octopus bimaculatus Two-spot octopus OCBI Description: The most common octopus in rocky intertidal areas; they have good camouflage, and can be difficult to see.

CHITONS: Molluscs with 8 small, overlapping plates. Scientific Name Common Name Abbreviation Mopalia muscosa Mossy chiton MOMU Description: A medium (up to 60 mm long) chiton that has a very heavy, mossy looking girdle. Stenoplax conspicua Conspicuous chiton STCO Description: A large (up to 100 mm long) chiton that has greenish-white plates and a thin (for its size), pinkish girdle. Nuttalina fluxa California Chiton NUFL Description: A small chiton, usually 40 mm or less in length. The girdle is brown to pink in color and has several spine. The California chiton is found in pits in the rocks in the upper and mid-tidal zone and is the most common chiton in So California.

ECHINODERMS Scientific Name Common Name Abbreviation Asterina miniata Bat star ASMI Description: A somewhat puffy 5-armed sea star that is commonly found in the intertidal zone; orange and red are common colours, but some are speckled, and they can also be grey, purple or yellow; diameter can reach up to 400 mm. Pisaster ochraceous Ochre star PIOC Description: A normally 5-armed sea star that is often found in the intertidal zone; yellow, orange, brown and purple are common colours, and all have patterns of white beading on the surfaced Diameter can reach up to 1 meter. Pisaster giganteus Giant sea star PIGI Description: A normally 5-armed sea star that is often found in the intertidal zone; they are usually greyish-brown with blue and white spots over their top surface; diameter can reach up to 1 meter. Ophioplocus esmarki Smooth brittle star OPES Description: This brittle star has short (up to 60 mm), smooth arms coming from a round, flat central disc that is 10-12 mm in diameter. Ophionereis annualta Striped brittle star OPAN Description: This brittle star has long (up to 120 mm), banded arms and a puffy spines, and a puffy central disc that is 10-12 mm in diameter. Ophioderma panamense Soft brittle star OPPA Description: This dark coloured brittle star has long (up to 180 mm) arms with white bands near the tips that emerge from a large (up to 25 mm), puffy, pentagon- shaped central disc. Ophiothrix spiculata Spiny brittle star OPSP Description: This brittle star is generally yellowish brown, but parts can be bright red, bright orange, or even bright blue; the central disc is star shaped, puffy, and usually about 15 mm in diameter; the legs are banded, very spiny, and about 90 mm long. Parastichopus parvamensis Warty sea cucumber PAPA Description: This echinoderm is orange, and shaped like a cucumber; it has tube feet along the bottom, and a number of wart-like projections. Strongylocentrotus purpuratus Purple (green) sea urchin STPU Description: This echinoid has short, blunt green (when young) or purple (when adult) spines coming from its ovoid body, which grows to be about 120 mm in diameter. Strongylocentrotus franciscanus Red sea urchin STFR Description: This echinoid has long, sharp red spines coming from its ovoid body, which grows to be about 200mm in diameter. VERTEBRATES: While there are many fish that swim through the intertidal area, you may find some of these under rocks. Scientific Name Common Name Abbreviation Gobiesox rhessedon California cling fish GORH Description: A small fish (to 60 mm) with a large head that looks like a tadpole; they have a sucker on the bottom of their heads that they use to attach to rocks and other surfaces. SPONGES: Sponges are stationary, amorphous animals that grow on rocks, dead shells, and some slow moving animals. Scientific Name Common Name Abbreviation Acarnus erithacus Red volcano sponge ACER Description: This sponge is bright red with small volcano like projections. Taxodocia spp White sponge TASP Description: This sponge is white or yellowish-white with small volcano like projections. Verongia aurea Sulphur sponge VEAU Description: This sponge is bright yellow with small volcano like projections. PLANTS: There’s only 1 plant that grows in rocky intertidal areas. Scientific Name Common Name Abbreviation Phyllospadix scouleri. Surf grass PHSC Description: A thin bladed grass that attaches to rocks. ALGAE: They can be green, brown or red. They have no vascular structures like most plants do. GREEN ALGAE: Green plant-like organisms, grow attached to rock or sand Scientific Name Common Name Abbreviation Cladophora sp. Green pincushion algae CLSP Description: Tufts of green algae that looks like moss. Codium fragile Dead man’s fingers COFR Description: A solid, branching dark green algae that attaches to rocks. Enteromorpha sp Filamentous algae ENSP Description: A stringy green algae. Ulva californica Sea lettuce ULCA Description: A wavy green algae that looks a little like lettuce leaves. : Brown plant-like organisms typically attach to rocks Colpomenia sinuosa Bubble algae COSI Description: A brown algae that grows in clumps that look like bubbles. Egregia menziesii Feather boa kelp EGME Description: A brown algae with long, fringed fronds. Eisenia arborea Sea palm EIAR Description: A stalked brown algae with many fronds at the top that looks like a small palm tree. Pelvetia fastigiata Green rock weed PEFA Description: A flat, branching greenish brown algae that attaches to rocks. Sargassum agardhianum Sargasso weed SAAG Description: A dark brown algae with very thin fronds that have many branches with lots of bubbles on them. : Purplish-red to reddish green algae, may turn brown when they dry. Usually attach to rocks or shells Fauchea laciniata Iridescent red algae FALA Description: A soft, flattened red algae with which has a bluish irridescent sheen. Plocamium cartilagineum Soft red algae PLCA Description: A soft, flexible, branching red algae. Porphyra perforata Red sheet algae POPE A membranous red alga that grows as deep purple to light red sheets. It is shiny and glossy in appearance when wet, and turns to a greenish brown or pinkish brown as it dries. CORALINE ALGAE: Either short, stiff, branching tufts of pink to white or encrusting white or pink growths. Corallina vancouverensis Red coralline algae COVA Description: A hard, branching pinkish red algae. Lithothamnia spp. Encrusting coralline algae LISP Description: A hard white, pink or red algae that grows directly on rocks and shells.