ONE HUNDRED COMMON MARINE ANIMALS OF SAN DIEGO BY WESLEY M. FARMEI l_l B R AS Y ,ine Biolcgical lebcrstory 1964 A\Non-Technical Guide WOCU^ hulE, MASS. Occasional Papers of the San Diego Society of Natural History Number 14 San Diego, California August, 1964 Cover Drawing - The lined shore crab, Pachygrapsus crassipes, is commonly seen along the coast's rocky shores. See page 16. ONE HUNDRED COMMON MARINE ANIMALS OF SAN DIEGO This guide will acquaint the visitor to the sea shore with the most common marine animals he will find. Although there is not space to mention all our marine animals, it describes and illustrates 100 animals found on the rocky coasts, sandy beaches, and bays. To observe and enjoy these animals, it is not necessary to destroy them. During seven months of 1957, Mr. Jack Littlepage and I watched the collecting of marine animals at Bird Rock, one of the best tidepool areas in La Jolla. By actual count, 1940 people collected 846 starfish and brittle stars, 966 crabs, and 3917 shellfish, including 376 green abalone, mostly under the legal size. We estimated that more than 10,000 animals were removed during this period. Although it is worth while to collect specimens for study, many people thoughtlessly take more than they need, only to discard them later. Most of the animals taken probably could better have been observed and then left for others to enjoy. Actually, most casual collectors are ignoring state laws. Anyone 16 years of age or over should have a sport fishing hcense ( $3 per year ) to take fish, shellfish, or crustaceans (lobsters, crabs, etc.), except when fishing from a public pier. Anyone collecting animals of other kinds is required to have a collecting permit; the fee is $5 per year or, for certain students, $1. For further information, call the local office of the California Department of Fish and Game. As a matter of conservation, you should always replace the rock that you roll to see what lurks beneath. Otherwise, the plants on the rock will die for want of sunUght, and the animals formerly beneath it will die of exposure. So roll it back. ACKNOWLEDGMENTS I am indebted to Miss Judy Strupp for comments in the early pre- paration of this guide and to Mr. Clinton Collier, Mr. Emery Chase, Dr. Reid Moran and Dr. Richard Banks for reading the manuscript and giving valuable suggestions. The large transparent shrimp is re- drawn from Johnson and Snook, Seashore Aninmls of the Pacific Coast, and the fish were redrawn from Bamhart, Marine Fishes of Southern California, University of California Press. All drawings are by the author. WHEN TO LOOK On boat docks, which rise and fall with the tide, one time is as good as another — just lean over and look. But for studying shore life, the lowest tides are best, especially on exposed rocky coasts. In late fall, winter, and early spring, the lowest tides are in the afternoon. In late spring, summer, and early fall, they are early in the morning, usually before daylight. WHERE TO LOOK Marine animals live in all possible habitats, including exposed rocky shores and sandy beaches of the ocean, sandy beaches or mud flats of bays, pilings, and bottoms of boats and other floating objects. Each habitat has its peculiar complement of animals, some occurring more generally, some very restricted as to depth, turbulence, or tem- perature of water and as to position on or under rocks, or in mud. In the intertidal zone, where exposure to the air varies with height, there is a corresponding zonation of animal life, many animals living there only in tide pools where they are never out of water. On rocks and other objects affording solid attachment, real estate is at a premium, and plants and animals cover all available space, even each other. One of the best places for rocks and tide pools is the Bird Rock area, where many small rocks provide shelter for a great variety of sea life. Sandy beaches, affording no foothold against the pounding surf, are relatively barren of life. But even here are animals, such as the burrowing sand crab, specially adapted to this difficult environment. And in the kelp hold fasts that have washed ashore, numerous animals can be found. Pier pilings support a crowded animal community. Usually mussels and barnacles predominate, but a closer look will reveal many other creatures. Likewise, pilings and floating objects in the quiet water of bays have their own crowded communities, as does the riprap on the sides of islands and points in the bays. The Mission Bay middle jetty has an assortment of sea life some- what different from that of other localities, perhaps because of the movement of water from the San Diego flood control channel. FURTHER INFORMATION This guide covers only the most common and conspicuous animals. To identify other animals that you may find, and to learn more about those included here, see the more complete books listed here. Hedgpeth, Joel, and Sam Hinton. 1961. Common Seashore Life of Southern California. Naturegraph Company, Healdsburg, Cali- fornia. 64 pp. Johnson, Myrtle E., and HaiTy J. Snook. 1927. Seashore Animab of the Pacific Coast. The Macmillan Company, New York. 659 pp. Light, S. F., et ah 1954. Intertidal Invertebrates of the Central Cali- fornia Coast. University of California Press, Berkeley and Los An- geles. 446 pp. MacGinitie, G. E., and Nettie MacGinitie. 1949. Natural History of Marine Animals. McGraw-Hill Book Company, New York. 473 pp. Ricketts, Edward F., and Jack Calvin. Revised by Joel W. Hedgpeth. 1952. Between Pacific Tides. Stanford University Press, Stanford, California. 516 pp. ANIMAL PHYLA The milHon-odd kinds of animals are built on about 15 different major plans and so fall into about 15 major groups, each called a phylum (plural phyla). Most of the largest and most familiar animals, the mammals (including ourselves), birds, reptiles, amphibians, and fish, all have backbones and have various other similarities in struc- ture: they belong to the phylum Chordata. The very numerous and also very familiar insects, spiders, and crabs are built on a very different plan, for example having their skeleton outside instead of inside: they belong to the phylum Arthropoda. Clams, earthworms, starfish, sponges, and jellyfish each are built on entirely different plans and each belong to a different phylum. Among the marine animals represented in this guide are many strange creatures, representing 10 phyla. SPONGES The sponges are very primitive sedentary animals, which you might scarcely recognize as animals at all. Some live in fresh water, but most are marine. Water taken in through pores and circulated through canals carries food and oxygen to all parts of the animal. The skeleton of the sponge is of fibrous material ( spongin ) or of glassy or calcareous spicules. Bath sponges are the skeletons of certain tropical sponges— or were before the days of plastics. Our sponges have no commercial value. SULPHUR SPONGE, Verongia thiona. Sulphur sponges can grow to about 7 or 8 inches in diameter. The animal is yellow, with an occa- sional brown color on its surface, and has a sulphur-like odor. Local Distribution: On the underside of rocks in the low tide zone of the rocky coast. COELENTERATES The coelenterates are the major group including jellyfish, sea ane- mones, and corals. They are mostly marine, with a few in fresh water. The body has a single opening, the mouth, surrounded by tentacles that capture the food. The Portuguese man-of-war and various jelly- fish are known and feared for their painful stings; but the other coelen- terates also have tiny poison-hypodermics ( nematocysts ) . The stinging cells of the sea anemone cannot penetrate the thick skin of our fingers, but don't stick your tongue in one. GREEN SEA ANEMONE, Anthopleura xanthogrammica. The sea ane- mone in open or feeding position, with numerous radiating tentacles, is truly a flower of the sea. When disturbed or when exposed by low tide, it contracts into a flabby ball covered with small rocks and bits of sand. The green anemone may reach a diameter of 12 inches, but small ones 1 to 2 inches across are more common. The color varies from a deep green through white, lavender, and pink, but never red or maroon. Range: From Sitka, Alaska, to Panama. Local Distribu- tion: In the high tide zone. BROODING ANEMONE, Epiactis prolifera. The brooding anemone generally has a ring of 5 or 6 young around its base, where they develop from small pits. It is green-lavender, or brown, and up to % inch wide. Range: Puget Sound, Washington, to Point Loma. Local Distribution: On brown algae or under rocks along the rocky coast, and at times in Mission Bay. ^^••x.. ..-^^^i\ i'K ■^. %;'^-^^ t ■ y Sulphur Sponge Green Sea Anemone Brooding Anemone FLATWORMS The flatworms comprise a major group whose best-known members are parasites— the tapeworms and flukes. Several free-living flatworms may be seen by the visitor to the rocky sea shore. They are broad and flat, dark above and white beneath. One is the salt-and-pepper flat- worm, which attains a length of about 2 inches. It is white with black specks. Another is light orange, and still another olive drab. Local Distribution: Under rocks along the coast. MOSS ANIMALS The moss animals (Bryozoa) are tiny animals forming sedentary colonies which often are mistaken for delicate seaweeds. A hand lens will reveal the numerous individuals, often no more than 1/25 of an inch across, each with a beak-like structure. The colonies of different kinds vary from feather-like to disk-shaped and may be several inches wide. Living moss animals vary in color from deep red-brown to white. Some appear as white disks on the fronds of kelp or as white patches on other algae. Range: World-wide. Local Distribution: On floats and docks in Mission Bay, on jetties and in rocky areas at very low tide. SEGMENTED WORMS SERPULID WORM, Laeospira sp. This serpulid worm appears as a small white spot on just about everything. The calcareous tube is about 1/16 inch wide. The shell is white, but the living animal is bright red. Dexiospira spirillum is a similar animal, but is coiled to the right rather than to the left. Local Distribution: Very common on rounded rocks and on kelp fronds that have washed ashore, and occasionally on the backs of crabs and other solid surfaces. SIPUNCUUD WORMS RICH BROWN PEANUT WORM, Dendrostoma spp. When disturbed, the peanut worm is usually contracted into a peanut shape. If placed in a bottle of sea water for a while, it will extend its gill-tipped mouth, which is on the end of a long stalk. Dendrostoma pyroides lives under rocks in the sandy substrate, while D. zostericolum, a similar species, lives in the roots of surf grass. Both worms attain lengths of about 2 inches. They are smooth rich brown. Local Dis- tribution: Along the rocky coast at the low tide level. 6 Salt-and-pepper Flatworm Moss Animals Serpulid Worm Rich Brown Peanut Worm ARTHROPODS The arthropods make up the largest phylum of animals, including the insects, spiders, centipedes and some others, mostly on land, and the crustaceans, a major marine group. The arthropod wears its skele- ton outside like a suit of armor, with joints where it can bend. The name "arthropod" refers to the jointed legs. To grow after the skeleton has hardened, it must shed the skeleton and form a new one. The crustaceans include crabs, lobsters, shrimp, sand fleas, barnacles, and many others. CAPRELLID or SKELETON SHRIMP, Caprella spp. Caprellids are stick- like animals (amphipods) difficult to see because they blend so well with the tunicates, hydroids or algae to which they cling. They reach more than an inch long and are brownish. The female has a brood pouch to carry her eggs and larvae. There are about 18 kinds of caprellids found along the coast. Local Distribution: Found com- monly about the floats in bays. SAND PILL BUG, Tylos punctatus. This animal is similar to the garden pill bugs and will curl up into a ball (like a pill) when handled. It is about /4 inch long and is tan or light gray. Pill bugs belong to the group of crustaceans known as isopods. Range: Southern California. Local Distribution: Located by its mole-like holes on sandy beaches. ROCK LOUSE, Ligia occidentalis. This evasive animal is often seen moving about the rocks near the high tide line or in the spray zone. If submerged for a long time it will drown. It is about I/2 inches long and is olive drab or dark gray. Range: Sacramento River to the Gulf of California. Local Distribution: On rocks in the spray zone and under drying kelp washed ashore near the rocks. CALIFORNIA SPINY LOBSTER, Panulirus interruptus. The California spiny lobster is occasionally seen in the tide pools at very low tide, particularly in the summer. It is reddish-brown and up to 2 feet long. Range: Point Conception, California, into Mexico. Local Distribu- tion: On rocky shores near and below the low tide line. 8 Caprellid Sand Pill Bug Rock Louse California Spiny Lobster 9 LARGE TRANSPARENT SHRIMP, Hippolysmata californica. As many as a dozen large transparent shrimp can be found under a rock at the low tide level. They move about quickly and are difficult to capture. The large transparent shrimp is up to 2 inches long with even longer antennae. The body is transparent with numerous red stripes. Range: Santa Barbara, California, to Ensenada, Baja California. Local Dis- tribution: Under rocks at the low tide level along the coast. BROKEN-BACK SHRIMP, Spirontocaris picta. Though it is common, the broken-back shrimp is sometimes difficult to see because its color blends well with its tide pool background. It is up to an inch long. There are several similar shrimps, distinguished by head shape. Local Distribution: In the tidal pools of the rocky coast. PISTOL SHRIMP, Cragon dentipes. At times during a very low tide, one can hear the snapping sound caused by the elusive pistol shrimp. One claw is greatly enlarged and modified to produce this sound. If handled roughly, the claw will fall oflF, but later the animal will grow a new one. The pistol shrimp attains a length of about 2 inches and is greenish. Range: San Francisco, California, to Cape San Lucas, Baja California. Local Distribution: Generally found in the roots of surf grass at very low tide. LONG-FINGERED SHRIMP, Betaeus longidactylus. The sexes of the long-fingered shrimp can be distinguished by their claws. The male, pictured here, has two extraordinarily long claws, generally half as long as the body. The female is small-clawed. The long-fingered shrimp is about 2/2 inches long. It varies from blue and blue-green to olive brown. Range: Elkhorn Slough, California, to San Diego. Local Dis- tribution: Under rocks at low tide level. ROCKY SHORE GHOST SHRIMP, CaUianassa calif orniensis. The ghost shrimp lives in a tunnel in the sand in association with the blind goby. It is fairly common and can generally be found by digging a hole in the sand under rocks. ( One should always put the rocks back in place.) This shrimp may be 2/2 inches long. It is generally whitish or cream colored. One claw is greatly enlarged. Range: Santa Monica, California, to Todos Santos Bay, Baja California. Local Distribution: Under rocks of the protected rocky coast and in burrows in the sand substrate. 10 Large Transparent Shrimp Broken-back Shrimp Pistol Shrimp Long-fingered Shrimp Rocky Shore Ghost Shrimp 11 At first glance, you might never suspect that barnacles are related to sand fleas, pill bugs, and crabs, for they grow attached to rocks and whales and things, and they have coarse shells. But inside the shell, the body and legs are jointed. The swimming larva looks more like a normal crustacean, but then it settles down on its back, develops a shell, and kicks its feet in the water to catch food. Some barnacles have volcano-shaped shells, attached directly to the rock or whatever, but the goose barnacles have a flexible stalk. PACIFIC GOOSE BARNACLE, Pollicipes polymerus. The Pacific goose barnacle has a flexible stalk, and the upper end is encased in a series of valves through which food-capturing feet protrude. It attains a length of about 3 inches. Range: Bering Strait to central Baja CaH- fornia. Local Distribution: Rocky headlands and pier pilings in the upper tide range, often with the California mussel. RED-AND-WHITE BARNACLE, Balatius tintinnabulum. The red-and- white barnacle is about % inch across and is pink with white markings. Range: Southern California. Local Distribution: On rocky coasts and pilings. THATCHED BARNACLE, Tetraclita squamosa. The thatched barnacle is sometimes solitary, but usually lives in clusters. The sides of the scutum (shell) give the appearance of being thatched; hence its name. It is up to 2 inches wide. It is light pink, but at times it appears green because of green algae which grow on it. Range: Farallon Islands, Cafifornia, to Baja California. Local Distribution: On jetties and prominent rocks in the intertidal region. ACORN BARNACLE, Balanus glandula. The acorn barnacle is dingy white, with heavily ribbed plates. It reaches a diameter of nearly half an inch. Range: Aleutian Islands to Ensenada, Baja California. Local Distribution: Common on rocky coasts and especially on rocks in bays, in the upper tidal area. SMALL ACORN BARNACLE, Chthamalus fissus. The small acorn bar- nacle is found in close association with the acorn barnacle, from which it is readily distinguished by its neat smooth surface, its lesser width (about Vs inch), and its darker color (dark tan). Range: Santa Barbara, California, to northern Baja California. Local Distribution: Common in bays in the upper tidal zone and along the rocky coast. 12 Thatched Barnacle Acorn Barnacle Small Acorn Barnacle 13 HERMIT CRAB, Pagurus spp. When you see a small shell moving at more than a snail's pace, very likely the snail doesn't live there any more. The hermit crab sets up housekeeping in an abandoned snail shell, and on outgrowing it, moves to another. The crab generally pulls into the shell when disturbed but will soon reappear if held still. Living in the snail shell, near the opening, along with the hermit crab, the white slipper shell {Crepidula mimmaria) can often be found. Local Distribution: On rocky beaches near the high tide line and on floats in bays. COMMON SAND CRAB, Emerita analoga. The presence of the com- mon sand crab is shown by a characteristic V-shaped ripple in the sand after a wave moves back to the sea. This is caused by the protruding eyes and antennae. The common sand crab is yellowish brown or gray and up to an inch long. Range: Oregon to South America. Local Distribution: In sandy beaches. PORCELAIN CRAB, Petrolisthes spp. The porcelain crabs are extreme- ly flattened and rounded, with large, smooth, flat claws, which on occasion are quickly shed. They are olive drab and usually under half an inch long. The antennae are on the outer side of the eyes and are extremely long. One porcelain crab (P. cinctipes) is common on the outer coast; another (P. eriomerus), very similar in appearance, occurs in bays. Range: British Columbia to the Gulf of California. Local Distribution: Under rocks and in mussel beds and, in Mission Bay, on floats and pilings. KELP CRAB, Pugettia producta. The kelp crab is easily distinguished by the straight, parallel sides of the carapace ( back ) , each side bearing 2 large spines. The prominent rostrum (front) is deeply split. Small specimens under an inch are often found in algae. The carapace is smooth and up to 5 inches wide. The color varies with age: small individuals are olive-brown above and spotted with white below; adults are brilliant red above and red with white spots below. Range: Alaska to Baja California. Local Distribution: Common on algae and surf grass in rocky areas. SOUTHERN KELP CRAB, Taliepus nuttallii. The southern kelp crab lacks the prominent spines that the kelp crab has on the carapace. It is up to 4 inches across the carapace. It is dark red-brown. Range: Point Conception, California, to Ballenas Bay, Baja California. Local Distribution: In surf grass and algae below the low tide line. 14 Kelp Crab Southern Kelp Crab 15 RED CRAB, Cycloxanthops novemdentatus. The claws and the front part of the carapace of the red crab are covered with fine granules. The carapace is wider than long, is slightly flattened, and lacks the large triangular points typical of the Cancer crabs. A large individual may be 2/2 inches long and 4 inches wide. The red crab is brilliantly colored, varying from a bright red to a deep purple. Range: Monterey, California, to Baja California. Local Distribution: Found under rocks, half covered with sand. COMMON ROCK CRAB, Cancer antennarius. The common rock crab is much wider than long; it reaches a length of 4 inches and a width of 7 inches. Distinguishing characteristics are the black-tipped claws and the red spotting on its under surface; otherwise it is red-brown. The front edges of the carapace have prominent triangular projections. Range: British Columbia to Baja California. Local Distribution: Found half buried in sand around rocks. MASKING CRAB, Loxorhynchus crispatus. The masking crab is some- what triangular, with a widely split rostrum (front) which points slightly downward. It reaches a length of 4/2 inches. The related sheep crab (Loxorhynchus grandis), less often seen, may be distinguished by its upturned rostrum and larger size. The masking crab's inflated carapace (back) and the legs bear short stiff hairs, to which it attaches small bits of seaweed. The walking garden of seaweeds loses all resemblance to a crab. Range: Point Reyes, California, to San Diego. Local Distribution: Found occasionally under ledges overgrown with algae. LINED SHORE CRAB, Pachygrapsus crassipes. The Uned shore crab is the crab most often seen along our coast. It feeds on both plant and animal material and hides under rocks when disturbed. It is generally deep red or green and attains a width of about 2 inches. Range: Oregon to the Gulf of California. Local Distribution: In all rocky areas, occasionally on floats and pilings. MUD-FLAT CRAB, Hemigrapsus oregonensis. Hairy legs are a distinc- tive characteristic of the mud-flat crab. The mud-flat crab attains a width across the carapace of one inch. It is greenish-gray or muddy yellow. Range: Alaska to Mexico. Local Distribution: Under rocks in the mud of San Diego and Mission bays. 16 Red Crab Common Rock Crab Masking Crab Lined Shore Crab Mud-flat Crab 17 MOLLUSKS The mollusks is the major group including clams, snails, chitons, and octopuses. With some 60,000 kinds, mollusks are second only to the arthropods in numbers. They are soft-bodied, mostly with hard shells, but their shells and bodies are relatively massive and not delicately jointed like those of the arthropods. Most mollusks are marine, though some clams and many snails live in fresh water and many snails live on land. The mollusks fall into six classes, four of which are represented in this guide. The pelecypods or bivalves, such as clams and mussels, have two shells, or valves, hinged at the top, and an axe-shaped foot which many of them use for digging their way into sand or mud. The gastropods, such as snails and slugs, usually have a single spirally coiled shell, but may have none. The chitons have a shell of eight separate overlapping plates in a row. The cephalopods, such as octopuses and squids, have no external shell; they have eight or ten arms, with suction discs. TWO-SPOTTED OCTOPUS, Octopus bimaculoides. Below its true eyes the two-spotted octopus has two false eyes ringed with blue and darker than the rest of the body. It attains a diameter of about 2 feet. It lies in wait for a passing fish or crab, then darts out and captures it. Crabs seem to be its favorite food. The animal is usually some shade of brown; when disturbed it may become warty and change color rapidly. Range: San Pedro, California, to Panama. Local Distribu- tion: Rocky areas. BEAN CLAM, Donax goitldii. At times the sandy beach will be covered with thousands upon thousands of bean clams. The bean clam is about an inch long, varying in color pattern but generally cream with purplish-black markings. Often the clam is bearded with a tuft of hydroids (Clytia bakeri), a colonial coelenterate (see page 4). Range: San Luis Obispo, California, to Mexico. Local Distribution: Sandy beaches along the coast. BROAD-EARED SCALLOP, Pecten latiauratus. The broad-eared scallop attaches itself to the surface of rocks and algae by means of thin threads. When not attached, it can swim by "jet propulsion", snapping the valves of the shell rapidly together. It is light orange-brown and about an inch long. Range: Vancouver Island, British Columbia, to San Diego. Local Distribution: On kelp washed ashore, on eel grass and algae in bays and kelp beds, and occasionally on floats. 18 «=^irr«pit* ;er-ir^{«=» Two-spotted Octopus Bean Clam Broad-eared Scallop 19 CALIFORNIA MUSSEL, Mytilus calif ornianus. The California mussel shell has a tough brownish-black chitonous covering, which may be worn off in places to expose a purplish-black and white shell. It is commonly 4 inches long, rarely as much as 8 inches. Range: Alaska to Mexico. Local Distribution: On rocky headlands and on pier pilings. BAY MUSSEL, Mytilus edulis. The bay mussel lives in quiet waters, in contrast to the California mussel, which lives on the open coast. The shell of the bay mussel is about 2 inches long, smooth, and black. Range: Around the world in north temperate seas; on this coast from Alaska to Baja California, Local Distribution: On wharf pilings, floats, and rocks in bays. PLATFORM MUSSEL, Septifer hifiircatus. The platform mussel is a solitary mussel found under rocks. It is also known as the branch- ribbed mussel because of the numerous ribs on the shell. It sometimes attains a length of 2 inches. It is purplish-black, sometimes with white eroded areas. Range: Northern California to the Gulf of Cali- fornia. Local Distribution: Under rocks along the coast. NATIVE OYSTER, Ostrea lurid a. The native oyster is not very sym- metrical; it may be circular or elongated, nearly flat or bent. It is generally off-white and up to 2 inches wide. Oysters are good to eat and are cultivated in northern bays and sloughs. Range: Sitka, Alaska, to Cape San Lucas, Baja California. Local Distribution: In San Diego and Mission bays, on rocks and pilings. HARD-SHELL COCKLE, Chione tindutella. The hard-shell cockle can be found alive only by digging in the mudflats, though the empty shells can be found on the shores of the bay. The shell is yellowish-white, about 2?4 inches wide. Animals less than I/2 inches cannot be taken. Range: San Pedro, California, to Mexico. Local Distribution: In the sandy mudflats of bays. 20 California Mussel Bay Mussel Platform Mussel GOULD'S BUBBLE SHELL, Bulla gouldiana. This animal has an orange- yellow body and a thin shell of mottled brown, sometimes 2^ inches long. Because of the placement of the gills, the bubble shell is thought to be closely related to the nudibranchs. Range: Santa Barbara, CaH- fornia, to Mexico. Local Distribution: Abundant in San Diego and Mission bays along the tide line. NAVANAX, Navonax inermis. The navanax is a sea hare about 7 inches long, with many yellow dots and a few blue dots on a brown back- ground. It lays a light yellow stringy egg mass, which is frequently seen. When disturbed, the navanax extrudes a yellow fluid smoke screen to discourage intruders. Range: Morro Bay, California, to Mexico. Local Distribution: On rocky shores and in bays. COMMON SEA HARE, Aplysia californica. The sea hare is a naked mottled brown animal up to 15 inches long. When disturbed, it ex- trudes a purplish fluid like a smoke screen in the water. Its large stringy masses of eggs are seen intermingled with the algae during November and March. Range: Bodega Bay, California, to the Gulf of California. Local Distribution: Common about rocks in the breed- ing season. COW-LIKE APLYSIA, Aplysia vaccaria. The cow-like aplysia is smooth and firmly muscular, as compared to the common sea hare, which is soft to the touch. It is called cow-like because of its grazing habits on the brown algae, Egregia, its principal food. It attains a length of more than a foot. It is deep purplish-black, with fine gray to white spots. Range: San Pedro, California, to Baja California. Local Dis- tribution: Common; usually scattered about the tidal flats on or between rocks. 22 Gould's Bubble Shell Common Sea Hare Cow-like Aplysia 23 BROWN-RINGED SEA SLUG, Diaulula sandiegensis. The brown-ringed sea slug is light brown to white with numerous dark brown rings on its mantle. It reaches a length of about 3 inches. Range: Japan and the Aleutian Islands to Cape San Lucas, Baja CaHfornia. Local Dis- tribution: Under rocks along the coast and in bays. BROWN SEA SLUG, Dendrodoris albopiinctatus. The brown sea slug is often found suspended from the surface film of a tide pool. It attains a length of about 2 inches. It is yellow or reddish-brown, with numer- ous, very small white dots. The central portion of the mantle is darker than the edge. The gills are nearly white and set well back on the dorsal (top) side. Range: Monterey, California, to Puertecitos, Baja California. Local Distribution: One of the common sea slugs in the tide pools and under rocks. TWO-SPOTTED SEA SLUG, Cadlina flavomaculata. The two-spotted sea slug can be distinguished from other nudibranchs by its black rhino- phores, sensory horn-like processes on the head. It attains a length of about /2 inch. It has a row of yellow spots along each side of its white mantle. Range: Vancouver Island, British Columbia, to Point Eugenia, Baja California. Local Distribution: Under rocks along the coast. MAGENTA-AND-YELLOW SEA SLUG, Glossodoris macfarlandi. The magenta-and-yellow sea slug attains a length of about 2/2 inches. It is bright magenta, with a yellow band around the rim of the mantle and three yellow stripes down the back. The processes near the tail are gills. This animal is generally known as a dorid. Range: Monterey, California, to the Coronado Islands, Baja California. Local Distribu- tion: Under rocks at low tide. HERMISSEND A, Hermissenda crassicornis. Hermissenda is white, orange, and opalescent blue, with red-brown processes (cerata) on its back. It is about 2 inches long. The cerata contain a dark core of liver substance. Hermissenda feeds on hydroids. Range: Sitka, Alaska, to Angel de la Guarda Island, Baja California. Local Distribution: Found on floats and docks, under rocks, and on the surface film of tide pools. It is our most common nudibranch. 24 Brown Sea Slug Brown-ringed Sea Slug Two-spotted Sea Slug Magenta-and-yellow Sea Slug Hermissenda 25 LIVID MACRON, Macron lividus. The livid macron has a thick shell about /4 inch long. It has a dark brown epidermis when alive. Range: Farallon Islands, California, to Baja California. Local Distribution: Under rocks intertidally along the coast. NUTTALL'S HORN MOUTH, Ceratostoma mittallii. The shell of Nut- tail's horn mouth has a sharp horn at the outer edge of the opening, whence the name. It is commonly about I/2 inches long, but may reach two inches. It is white or brown, or a mixture of both colors. The shell is generally rather lumpy. Range: Monterey, California, to Baja California. Local Distribution: On the Mission Bay jetties and other rocky areas. ANGULAR UNICORN, Acanthina spirata. The shell of the angular uni- corn is about 1/4 inches long, with a small sharp horn at the opening. Near the opening there are 10 or 12 light colored lines, with dark markings giving the shell a checkered appearance. Range: Puget Sound, Washington, to Socorro Island, Mexico. Local Distribution: On rocky jetties and rocks near the upper tide zone. CALIFORNIA HORN SHELL, Cerithidea californica. During a minus tide, the California horn shell can be found in great numbers on mud flats. It is dark brown or sometimes almost black, and over an inch long. Range: Bolinas Bay, California, to Baja California. Local Dis- tribution: On the mud flats of Mission and San Diego bays. TUBE-BUILDING SNAIL, Aletes squamigenis. This interesting snail gen- erally attaches itself to a rock and grows like a tubeworm, for which it can readily be mistaken. It generally grows in clusters of several individuals and is easily detected. The shell is several inches long and whitish, but the animal is almost black. Range: Monterey, California, to Peru. Local Distribution: Under rocks near shore. 26 Livid Macron Nuttall's Horn Mouth Angular Unicorn California Horn Shell Tube-building Snail 27 GRAY LITTORINE, Littorina planaxis. Among the limpets and barnacles of the spray area great numbers of the gray littorine, or periwinkle, can be found. It can be found as much as 20 feet above high tide. The dingy gray shell may be % inch high. The inner margin of the opening is large and flattened. Range: Washington to Baja California. Local Distribution: In the spray area on rocky cliflFs along the coast. CHECKERED LITTORINE, Littorina scutulata. The checkered littorine occurs only a few feet above the high tide line. It is smaller and slimmer than the gray littorine ( about }i inch ) and lacks the flattened area. It is brown or black, checkered with white. Range: Alaska to Baja California. Local Distribution: Along the rocky cliffs of our coast. ONYX SLIPPER SHELL, Crepidula onyx. The onyx slipper shell can be found as many as three deep, one on top of the other. It is light brown and may be 2 inches long. The inner side of the shell has a white shelf. Range: Monterey, California, to Chile. Local Distribu- tion: On rocks and on other shells in bavs where there is mud. CUP-AND-SAUCER LIMPET, Crucibulum spinomm. The outer surface of this shell may or may not contain many spine-like projections. Inside there is a small cup. The cup-and-saucer limpet attains a diameter of about an inch. This limpet is almost white. Range: Northern Cali- fornia to Chile. Local Distribution: On stones and backs of shells in San Diego and Mission bays. SOUTHERN MOON SNAIL, Polinices recluziana. A particularly inter- esting fact about the southern moon snail is that it mixes sand and eggs together into a sand-colored egg "collar", formed around its very large foot. The shell itself is a rich tan and may be 2 inches wide. Range: Crescent City, California, to Chile. Local Distribution: In San Diego and Mission bays on muddy sand. 28 Gray Littorine Checkered Littorine Onyx Slipper Shell Cup-and-saucer Limpet Southern Moon Snail 29 FILE LIMPET, Acmaea limatula. The file limpet has coarse ribs like the teeth of a file. The shell is about an inch long, tan or gray-green outside, white inside with black around the edge. Range: Crescent City, California, to San Diego. Local Distribution: In the high tide area of the rocky shore. ROUGH LIMPET, Acmaea scahra. The rough limpet is characteristically deeply scalloped along the edge and ribbed along the sides. It is relatively flat and measures up to /4 inch long. It is generally light tan. Range: North-central California to Socorro Island, Mexico. Local Distribution: On and under rocks. FINGER LIMPET, Acmaea digitalis. The finger limpet is rough textured, with a varied pattern because of erosion. It is generally greenish-tan or grayish and may be an inch long. Range: Aleutian Islands to San Diego. Local Distribution: Collected in clusters in the high tide area on rocky surfaces, generally about cracks. SEAWEED LIMPET, Acmaea insessa. The seaweed limpet grows on the stipe (stem) of the feather boa {Egregia, a brown alga) and appar- ently is rather limited to this habitat. The shell is smooth and reddish- brown, and about % inch long. Range: California. Local Distribution: On the brown alga Egregia. OWL LIMPET, Lottia gigantea. The meat of the owl limpet is reported to be very palatable when prepared like that of abalone. The shell is up to 3 inches long, rough and dull brown outside, but bluish-white toward the center and dark toward the edge inside. Range: Crescent City, California, to Cedros Island, Baja Cahfornia. Local Distribu- tion: Common in the high tide area of rocky beaches. VOLCANO LIMPET, Fissurella volcano. The volcano limpet is gener- ally oval, with an oblong "keyhole" at the center, suggesting the shape of a volcano. It is ashy-pink with 13 to 16 purplish rays and may be an inch long. Range: Crescent City, California, to Panama. Local Distribution: In the high tide zone on rocks. GIANT KEYHOLE LIMPET, Megathtira crenulata. The giant keyhole limpet is oblong and massive, sometimes 7 inches long. The foot of the living animal is orange-yellow. The shell is nearly covered by a black or tan mantle, as is the "keyhole." Range: Monterey, California, to Baja California. Local Distribution: On jetties and rocks along the coast. 30 File Limpet Rough Limpet Finger Limpet Seaweed Limpet Owl Limpet Volcano Limpet Giant Keyhole Limpet 31 SMOOTH BROWN TURBAN, Norrisia norrisii. The smooth brown tur- ban is about 2 inches wide. The shell is rich brown, and the living animal is a bright red. Range: Monterey, California, to Baja California. Local Distribution: On brown algae of the Mission Bay jetties and about rocks at very low tide along the coast. BLACK TURBAN, Tegiila fimebralis. The black turban is one of the first animals found at the rocky beach. It hides under rocks during the day and comes out at night. The shell is black, often with a purple tinge, although the top is usually worn away, exposing a white surface. It commonly reaches almost an inch in diameter. Range: Vancouver Island, British Columbia, to Baja California. Local Distribution: Upper tidal zone in rocky areas. RUSTY-BANDED TURBAN, Tegiila ligulata. The rusty-banded turban is generally found lower than the black turban. It is less than an inch high. It is a rusty-brown, its beaded lines spotted with black. Range: Monterey, California, to Mexico. Local Distribution: In the medium-low tide area of rocky beaches. WAVY TOP, Astraea undosa. Wavy top shells are conical and often more than 4 inches wide. The under surface is pearly, and the sides are covered with a fibrous brown epidermis giving it a rough appear- ance. Often the shell is covered with algae and hydroids. The oper- culum or "door" is thick and has two prominent curved ridges. Range: Laguna Beach, California, to Cedros Island, Baja California. Local Distribution: On rocky beaches and jetties. BLACK ABALONE, Haliotis cracherodii. The black abalone is smooth, greenish-black and up to 10 inches in length. It has 5 to 9 openings near the edge of its shell for the passage of oxygen-laden water. Range: Oregon to Baja California. Local Distribution: Under rocks along the coast. SOUTHERN GREEN ABALONE, Haliotis fulgens. The southern green abalone is about 10 inches long and dull reddish-brown, with 30 or 40 spiral ridges, and with 5 or 6 small slightly elevated circular openings along its edge. It is relatively low and flattened compared to the other abalones, which tend to be deeper bodied. Range: Farallon Islands, California, to the Culf of California. Local Distribution: Found in rocky intertidal areas, usually at the low tide level. 32 Smooth Brown Turban Black Turban Rusty-banded Turban Wavy Top Black Abalone Southern Green Abalone 33 CALIFORNIA CONE, Conus calif or nicus. The California cone has a con- ical shell about an inch long, upturned at the end of the long, narrow aperture. It is dull brown when alive. Range: Farallon Islands, Cali- fornia, to Baja California. Local Distribution: On rocky beaches and the flood control channel of the San Diego River. PURPLE OLIVE, Olivella biplicata. The purple olive snail can be de- tected in its home under the sand by a depressed trail. Digging in the sand at the end of the trail will usually produce the snail. The shell is highly polished, white and purplish, and up to % inch long. Range: Vancouver, Washington, to Baja California. Local Distribu- tion: In sandy areas of bays and the San Diego River flood control channel. CALIFORNIA MARGINELLA or "WHEAT SHELL", Hyalina californica. The California marginella has a highly polished smooth shell. As many as 6 or 7 may sometimes be found under a single rock. It is pale yellowish-white with a dark central band. Range: San Pedro, California, to Mexico. Local Distribution: Under rocks along the coast. HARTWEG'S CHITON, Cyanoplax hartwegii. Hartweg's chiton is oval, somewhat flattened, and appears relatively smooth to the naked eye. It attains a length of \)i inches. It has 8 olive green valves. Range: Alaska to the Gulf of California. Local Distribution: Found inter- tidally under rocks along the coast. CONSPICUOUS CHITON, Stenoplax conspicua. The conspicuous chiton reaches 4 inches in length. It is green, with white and pink in the centers of the valves. Range: Monterey, CaHfornia, to the Gulf of California. Local Distribution: Adhering to the underside of smooth rounded rocks that are partially buried in a sandy substratum. MOSSY CHITON, Mopalia muscosa. The mossy chiton usually has en- crusting plants and animals on the greenish-brown plates, causing it to blend well with its background. It reaches a length of about 2 inches. Along the mantle there are numerous hairy projections. Range: Shumagin Islands, Alaska, to Baja California. Local Distribution: In deep depressions that the animal has made in the rocks. 34 California Cone Purple Olive California Marginella Hartweg's Chiton Mossy Chiton Conspicuous Chiton 35 ECHINODERMS The echinoderms is the major group including starfish, sea urchins, sand dollars, and sea cucumbers. All are marine. They move or attach themselves by means of small but very numerous tube feet, each with a suction cup at the end. The echinoderms fall into five classes, of which four are represented in this guide. Starfish and sea urchins have many tiny pincers ( pedicellariae ) , which keep the animal free of homesteaders. If the starfish is held next to the back of your hand, the pedicellariae will pinch the hairs and as the starfish is moved away they will pull on them. SOUTHERN CALIFORNIA SEA CUCUMBER, Stichopus parvimensis. The southern California sea cucumber is a very soft cylindrical animal some 18 inches long, varying from yellow-brown to red-brown. The upper surface is covered with pointed warts, and the lighter under- side bears tube feet. Range: Laguna Beach, California, to Baja Cali- fornia. Local Distribution: On the surface of sand and algae or under rocks. PURPLE SEA URCHIN, Strongylocentrotiis purpurattis. The purple sea urchin is covered with short, blunt, moveable spines. It may reach a diameter of 2 inches. The color varies from green in the young to a deep purple in the adults. Range: Alaska to Cedros Island, Baja Cali- fornia. Local Distribution: Common locally on rock ledges and jetties, and under rocks. COMMON SAND DOLLAR, Dendraster excentricus. The sand dollar is, essentially, a flat sea urchin, and reaches a diameter of about 4 inches. Close examination will reveal tiny spines, corresponding to those of a sea urchin, though these are missing from the dead shell or "test" commonly found on the beach. Range: Alaska to Baja Cali- fornia. Local Distribution: Found in the flood control channel of the San Diego River, Mission Bay and La Jolla Shores. SEA BAT, Patiria miniata. This starfish may be distinguished by its short webbed rays. It may reach a diameter of 6 inches, but a more common size is 1 to 2 inches. The color varies from red to purple and orange to yellow. Range: Sitka, Alaska, to La Paz, Baja California. Local Distribution: Common on jetties and around rocks; large individuals are often found in Mission Bay. 36 Southern California Sea Cucumber Purple Sea Urchin ,.„*/„ , p:;c:i:cS^;.j:-Ji5S Common Sand Dollar Sea Bat 37 VARIABLE STARFISH, Linckia columhiae. This is a small starfish, some- times 5 inches wide, which is highly variable as to form and number of arms; it is almost never symmetrical. Often the central disk bears only one or two arms. The arms are round and smooth, varying from a dull red, spotted with orange or yellow, to a dull tan with brighter specks. Range: San Pedro, Cahfomia, to the Galapagos Islands. Local Distribution: Under rocks at low tide. SOUTHERN TWO-COLORED STARFISH, Fisaster giganteus. This is sim- ilar to the ochre starfish but smaller, and attains a length of about 5 inches. The knobby spines on the back are larger and do not form a pentagon on the central disk. One of the most distinctive character- istics of this animal is the color, usually an opalescent blue with the spines ringed with white. Range: San Luis Obispo, California, to Ensenada, Baja California. Local Distribution: Among rocks. OCHRE STARFISH, Pisaster ochraceus. This is a large stiflF-armed star- fish, densely covered with short rounded spines, which form a small pentagon on the central disk. It reaches a diameter of about 15 inches, but smaller specimens are more common. The color varies from yellow to brown or red to purple. This is by far the most common starfish of southern California. Range: Point Conception, California, to below Ensenada, Baja California. Local Distribution: Common on break- waters, jetties, and piers, and occasionally under rocks. SOFT STARFISH, Astrometis sertulifera. This animal is distinguished by the slender soft flexible arms, covered with many small spines. It may reach a diameter of 7 inches. It is reddish-brown, with a faint tinge of bluish-green around the base of the spines. Range: Santa Barbara, California, to the Gulf of California. Local Distribution: Under rocks. SOUTHERN SAND STAR, Astropecten armatus. The southern sand star is purplish-gray, and rarely more than 10 inches wide. A buried sand star can usually be located at low tide by a star-shaped disturbance in the sand. Range: Newport Bay, California, to Panama. Local Dis- tribution: On sand flats in San Diego and Mission bays. 38 Soft Starfish Southern Sand Star 39 RINGED SERPENT STAR, Ophionereis annulata. The ringed serpent star is brown and attains a diameter of 4 inches. The slender arms are ringed or spotted and have spines at acute angles. Range: San Pedro, California, to Central America. Local DisxRiBimoN: Under rocks along the coast. SAND-COLORED BRITTLE STAR, Ophioplocus esmarki. This animal re- sembles the banded-armed brittle star but is smaller, reaching a diameter of only 3/2 inches, with shorter arms, only about three times the diameter of the central disk. The disk is covered with small swollen scales, which give it a pebbled appearance. It is a uniform light sandy-pink. Range: Pacific Grove, California, to San Diego. Local Distribution: With other brittle stars under rocks. BANDED-ARMED BRITTLE STAR, Ophioderma panamensis. The banded- armed brittle star is one of the most abundant in this area and is one of the largest, sometimes reaching a diameter of 7 inches. It is dark brown with alternating light and dark bands encircling the arms. The solid-colored disk is finely granulated, with a notch over each arm. Range: San Pedro, California, to Panama. Local Distribution: Abundant under rocks. BLUNT-SPINED BRITTLE STAR, Ophiopteris papillosa. The blunt-spined brittle star may reach a diameter of 7 inches. It is brown, with numer- ous darker bands encircling the arms. Each arm bears 5 rows of close-set, erect, small, square-cut spines. Range: Pacific Grove, Cali- fornia, to Mexico. Local Distribution: Under rocks. SPINY BRITTLE STAR, Ophiothrix spiculata. The arms of the spiny brittle star are covered with spines that are longer, thinner, and more numerous than those of the blunt-spined brittle star. The central disk is so thickly covered with small spines that it often appears fuzzy. It attains a diameter of 7 inches. The color is highly variable but often is greenish-brown. Range: Monterey, California, to Central America. Local Distribution: Under rocks. 40 Blunt-spined Brittle Star Spiny Brittle Star 41 CHORDATES The chordates is the major group that includes the vertebrate animals — fish, amphibians, reptiles, birds, and mammals — all of which have backbones. The chordates also include three small groups of marine animals without backbones but with other striking points of resemblance to the vertebrates. The adult tunicate is sedentary, either solitary or forming colonies that might be taken for sponges. But the free-swimming tadpole-Hke young have gill slits and in other ways resemble fish. Tunicates are so called because of their tough outer "tunic", of a cellulose-like material. Though most larger fish retreat with the ebbing tide, some small ones survive the low tides in tide pools, where a little bit of high tide is trapped. They hide under rocks and seaweeds. STALKED SIMPLE TUNICATE, Styela montereyensis. The stalked simple tunicate is leathery brown, and about 8 inches long. Range: British Columbia to San Diego. Local Distribution: On the floats of docks and on pilings in bays. SIMPLE TUNICATE, Ciona intestinalis. The simple tunicate grows in great clusters, in the spring and summer, on the floats and docks in bays. It reaches a length of about 3 inches. It is greenish-yellow, with the internal anatomy showing through the thin body wall. Local Distribution: On pilings, floats, and docks in Mission and San Diego bays. CALIFORNIA MORAY EEL, Gymnothorax mordax. The moray eel has very sharp teeth and a vicious temper. It reaches 5 feet long, but 3-footers are seen in the tide pools. It is dark brown with yellowish markings. It generally feeds on octopus and fish. Range: Point Con- ception, California, to Cedros Island, Baja California. Local Dis- tribution: Intertidal areas at low low tide. OPALEYE, Girella nigricans. The opaleye can be distinguished in the tide pools by the white blotch on each side of its back, contrasting with its light to dark green overall color. It has eyes of an opalescent blue. It attains a length of 15 inches, but small ones about 3 or 4 inches are the rule in tide pools. The opaleye feeds on seaweeds covered with animal life, such as bryozoans and hydroids. Range: San Francisco, California, to Cape San Lucas, Baja California. Local Distribution: In rocky areas and tide pools. 42 Simple Tunicate Opaleye 43 BLIND GOBY, Typhlogobiiis calif or niensis. The blind goby is uniformly pink and has no scales. It grows to a length of 2/2 inches. When young, it has two black dots in the usual location of the eyes; within 6 months the cornea becomes twisted and overgrown by flesh, making the eye non-functional. Range: Point Vicente, California, to Cedros Island, Baja California. Local Distribution: Fairly common at Bird Rock, La Jolla, though seldom seen because it lives under the surface. One or two blind gobies may be found in the burrow of a ghost shrimp. WOOLY SCULPIN, Clinocottus analis. The wooly sculpin is often seen on the bottom of a tide pool, moving about in a jerky manner. It attains a length of 7 inches, although small specimens about 3 inches long are more common. Its color changes to match its background, but commonly it is mottled, pale greenish or blackish, and spotted with white dots. Range: Southern California into Baja California. Local Distribution: In tide pools. SPOTTED KELPFISH, Gibbonsia elegans. When a tide pool is ap- proached, its occupants generally hide in the algae or under rocks. If you wait quietly for a while, the spotted kelpfish, which blends well into the background, will begin to move about and can be detected readily. The spotted kelpfish, about 4 inches long, is brown- ish, with two prominent blue or brown spots on each side of the tail and above the pectoral fin. Range: Point Conception, California, to Ensenada, Baja Cahfornia. Local Distribution: In tide pools at very low tide. CALIFORNIA CLINGFISH, Gobiesox rhessodon. The chngfish is a flat- tened fish about 2 inches long with characteristically A-shaped pelvic fins with which it adheres to rocks. It is light brown. It is seldom seen because of its size, its protective color, and its ability to hide. Local Distribution: Under rocks at low tide. 44 Blind Goby Wooly Sculpin Spotted Kelpfish .5i*5r- California Clingfish 45 INDEX Abalone 32 Acanthina 26 Acmaea 30 Aletes 26 Anemone 4 Anthopletira 4 Aplysia 22 Arthropods 8 Astraea 32 Astrometis 38 Astropecten 38 Balanus 12 Barnacles 12 Beach hopper 8 Betaeus 10 Brittle star 40 Bryozoa 6 Bubble shell, Gould's 22 Bulla 22 Cadlina 24 Callianassa 10 Cancer 16 Ceratostoma 26 Cerithidea 26 Chiton 34 Chione 20 Chordates 42 Chthamalus 12 Ciona 42 Clam, bean 18 Clinocottus 44 Clingfish, California 44 Clytia 18 Coelenterates 4 Cockle, hard-shell 20 Cone, Cahfornia 34 Conus 34 Crab 14,16 Cragon 10 Crepidula 14,28 Crucibulum 28 Cucumber, Southern Calif. 36 Cyanoplax 34 Cycloxanthops 16 Dendraster 36 Dendrodoris 24 Dendrostoma 6 Dexiospira 6 Diaulida 24 Donax 18 Echinoderms 36 Emerita 14 Epiactis 4 Fissurella 30 Flatworms 6 Gibbonsia 44 Girella 42 Glossodoris 24 Gobiesox 44 Goby, blind 44 Gymnothorax 42 Haliotis 32 Hemigrapsus 16 Hermissenda 24 Hippolysmata 10 Horn mouth, Nuttall's 26 Horn shell, Cahfornia 26 Hyalina 34 Isopod 8 Kelpfish 44 Laeospira 6 Ligia 8 Limpet 28,30 Linckia 38 Littorina 28 Pisaster Littorine 28 Polinices Lobster, California spiny 8 Pollicipes Lottia 30 Pugettia Loxorhynchus 16 Rock louse Macron, livid 26 Sand dollar, common Marginella, California 34 Sand flea Megathura 30 Scallop, broad-eared Mollusks 18 Sculpin, wooly Moon snail, southern 28 Sea hare, common Mopalia 34 Sea slugs Moray eel, California 42 Sea urchin, purple Moss animals 6 Septifer Mussel 20 Shrimp Mytilus 20 Slipper shell Navanax 22 Spirontocaris Norrisia 32 Sponge, sulphur Octopus 18 Sponges Olivella 34 Starfish Olive, purple 34 Stenoplax Opaleye 42 Stichopus Ophioderma 40 Strongylocentrotus Ophioplocus 40 Styela Ophiopteris 40 Taliepus Ophionereis 40 Tegula Ophiothrix 40 Tetraclita Orchestia 8 Tube-building snail Ostrea 20 Tunicate Oyster, native 20 Turban Pachygrapsus 16 Tylos Pagurus 14 Typhlogobius Panulirus 8 Unicorn, angular Patiria 36 Verongia Pecten 18 Wavy top Periwinkle shells 28 Wheat shell Petrolisthes 14 Worms Pill bug, sand 8 MBL WHOI Libra 5 WHSE 00004