Discovery Pools

Vocabulary flashcards covering key terms and definitions from the Discovery Pools notes.

Crimson Anemone (Cribrinopsis fernaldi)

Bright or light red-pink anemone with a column up to 10 inches tall; crown of slender, drooping tentacles; tentacles drape over the column and have zig-zag lines; can irritate skin; preyed upon by sea stars and some fish; diet includes invertebrates and fish.

Giant Plumose Anemone (Metridium farcimen)

About 1 meter tall at maximum, typically 50 cm or less; has 200+ thin tentacles; usually white but can be brown, tan, or pinky-orange; cauliflower-like shape; reportedly the world’s tallest polyp; base attaches to hard surfaces; resembles a white sock with a rock in the toe when tide is out; preyed upon by Pisaster sea stars; carnivorous—eats invertebrates, fish eggs, and some fish.

Painted Anemone (Urticina crassicornis)

Also known as Christmas anemone; color patterns range from blotched red and green to greenish, olive, brownish, or red; oral disk is pale yellow-green, pale lilac, or brownish; short radial bands outline the tentacles; tentacles usually the same color as the disk; can live up to 80 years; diet includes molluscs, crustaceans, sea urchins, and some fish.

Burrowing Green Anemone (Anthopleura artesmisia)

White tentacles line the oral disc used to attack invading anemones; column is pink or white on the buried portion and greenish/brownish on the exposed top due to symbiotic algae; preyed upon by sea stars; primarily eats invertebrates, fish eggs, and sometimes small fish.

Broadcasting (Sea Anemone Reproduction)

Reproduction by releasing eggs and sperm into the water for external fertilization.

Fragmentation (Sea Anemone Reproduction)

Asexual reproduction where part of the organism regrows into a new individual.

Nematocysts (Cnidarians)

Stinging capsule organs on cnidarian tentacles that often contain a venomous thread discharged to capture prey or defend against enemies.

Calcareous Tube Worms (Serpula vermicularis)

Live in calcium carbonate tubes they build; worm body up to 8 cm long; crown of radioles at the anterior end used for filter feeding and gas exchange; radioles can be red, pink, orange, with white bands.

Nemertean Ribbon Worm (Nemertea)

Range from a few millimeters to about 30 meters; most commonly ≤20 cm; unsegmented, without a differentiated head, often flattened; some species use other animals as hosts in mutualist, commensal, or parasitic relationships.

Polychaete Scale Worm (Polynoidae)

About 1 cm long; flat and broad with many short bristles along the sides; upper side shows a pattern of overlapping scales; well-developed head with long tentacles.

Common Acorn Barnacle (Balanus glandula)

Can extract oxygen from air and water; volcano-shaped shells white to gray often with a reddish-brown diatom coating; shell composed of 6 plates that fit tightly; 6 pairs of legs used for filter feeding.

Spot Prawn (Pandalus platyceros)

Brown with distinct white spots; largest shrimp in the North Pacific; protandric hermaphrodites (start male, become female); females larger than males; five pairs of swimmerets; bottom foragers feeding on shrimp, plankton, small molluscs, worms, sponges, and fish carasses; up to about 4 years; can change body color for camouflage.

Pacific Lyre Crab (Hyas lyratus)

Carapace resembles a lyre; typically brownish-red; legs have random orange-red banding; carapace often overgrown with barnacles; males typically larger than females.

Graceful Decorator Crab (Oregonia gracilis)

Decorates itself with algae, sponges, bryozoans, or hydroids attached by fine hooked setae; easily confused with longhorn decorator crabs but lacks white banding on claws.

Pygmy Rock Crab (Glebocarcinus oregonensis)

Oval carapace; dull brownish-red to reddish-orange; sometimes mottled, striped, or white; black claw tips; short hairy legs; carapace may have wart-like tubercles; nocturnal; feeds on barnacles and other invertebrates; can use body to plug shelter openings.

Rhinoceros Crab (Rhinolithodes wosnessenskii)

Carapace with triangular outline and a deep semicircular dorsal depression; claws and legs with spines and long setae; rostrum with a small horn; color typically yellowish-brown with white and orange.

Tubeworm Hermit Crab (Discorsopagurus schmitti)

Lives in an abandoned tube worm casing; red-brown color mottled with purplish red and grey; spots of yellow on legs; body inside tube is not curled.

Bering Hermit Crab (Pagurus beringanus)

Has 10 legs, but not all function; only 3 pairs outside the shell and 2 of those have claws; legs banded, white/pale blue prominent; claws reddish and spiny.

Widehand Hermit Crab (Elassochirus tenuimanus)

Right pincer larger than left; purplish-blue patches on inner leg segments; carapace and appendages reddish-brown, orange, yellow, and white; preyed upon by gunnels, snailfish, clingfish; primarily scavenges dead organic matter and may eat small invertebrates.

Bluespine Hermit Crab (Pagurus kennerlyi)

Red and yellow abdomen marbled with brown and white; 1st and 2nd walking legs red/tan with white patches; claws dark; large blue or white spines.

Pacific Red Hermit Crab (Elassochirus gilli)

Bright red/orange; lives in snail shells; right claw larger than left; primarily scavenges dead organic matter.

Tube Feet (Echinoderms)

Small active tubular projections on the oral face of echinoderms used for locomotion and feeding; more discrete on brittle stars; feeding function prominent in feather stars.

Madreporite

Essential component of the echinoderm water vascular system; a sieve plate that controls water intake and expulsion through which water moves in a regulated manner.

California Sea Cucumber (Parastichopus californicus)

Largest sea cucumber in the northeast Pacific; mottled brown-red on top with lighter sides and cream underside; lacks a true brain; breathes through its anus; deposit feeds on organic matter; preyed upon by sea stars, fish, sea otters, and humans.

Daisy Brittle Star (Ophiopholis aculeata)

Color variability to confuse predators; top side often pink, red, orange, blue, green, gray, or black with mottled patterns; can shed rays when disturbed; star-shaped body with a hard calcium endoskeleton; 5–7 spiny arms; suspension feeders that also scavenge using tube feet.

True/Mottled Sea Star (Evasterias troschelii)

5 rays; color range brown to blue-gray to rust; common to find scale worms on the underside; carnivorous; preys on molluscs, barnacles, sea squirts and more; found in rocky coastal areas.

Blood Sea Star (Henricia leviuscula)

Small central disk with 4–6 skinny arms; top side bright red/orange, may be tan, purple, or mottled; feeds on sponge, bacteria, and microscopic particles; uses a mucus stream to entrap prey and cilia to move to the mouth.

Vermilion Sea Star (Mediaster aequalis)

Bright red; covered with tightly packed flat-topped plates; consumes detritus from mud, dead animals, algae, encrusting sponges, bryozoans, sea pens, and sea squirts; preyed upon by morning sun stars.

Leather Sea Star (Dermasterias imbricata)

Smooth skin that can exude mucous; lacks spines; six to eight rows of papulae for respiration on each arm; swallows prey whole and digests it internally; often noted for garlic-like smell.

Ochre Star (Pisaster ochraceus)

Can tolerate exposure to air for up to 50 hours when shaded or moist; small light-sensitive spots at arm tips help locate shelter; color ranges purple, red, and orange; predators include sea otters and gulls; carnivorous; preys on molluscs and barnacles; can evert stomach into shells; prefers rocky habitats.

Velcro Sea Star (Stylasterias forreri)

AKA fish-eating star; covered with numerous pedicellariae (up to 50,000) that resemble tiny fish-hooks; primarily feeds on gastropods and chitons; color ranges from grayish to black-purple.

Red Banded Sea Star (Orthasterias koehleri)

Also known as painted star; banded with reddish and white-cream colors; five long arms; color variation includes red, white, or blue; has prominent spines; feeds on a wide range of invertebrates.

Rose Sea Star (Crossaster papposus)

Named for red, pink, or purple radiating rings on its back; fast mover among sea stars; has 8–16 arms; aboral surface with concentric red/white or yellow/orange rings; preys on anemones, sea pens, sea slugs, bryozoans, tunicates, nudibranchs, bivalves, and sometimes small stars; can live up to about 20 years.

Sunflower Sea Star (Pycnopodia helianthoides)

Largest, heaviest, softest, and fastest sea star in the North Pacific; up to about 3 feet in diameter; moves 5–10 feet per minute; aggressive predator that can steal prey from other sea stars; feeds on bivalves, snails, barnacles, chitons, sea urchins, other sea stars, sea cucumbers, sand dollars, and various crabs; eats entire prey; large, flexible body with a loosely articulated skeleton regulated by the madreporic system.

Stimpson’s Sun Star (Solaster stimpsoni)

9–12 arms with a dark purplish-blue stripe radiating from the central disk; body colors range orange, red, or pink; feeds on sea cucumbers, sea squirts, and sea pens; preyed upon by morning sun star.

Green Sea Urchin (Strongylocentrotus droebachiensis)

Smallest urchin along the Alaskan coast; typically eats kelp and other algae; can scavenger on fish and invertebrates; colors range green with dark banding; spines.

Purple Sea Urchin (Strongylocentrotus purpuratus)

Purple urchin with lighter or brighter purple spines; teeth renewed every ~75 days; indicator species for pollution; preyed upon by sea otters; diet includes brown and red algae and kelp; gonads (uni) used in sushi.

Red Sea Urchin (Strongylocentrotus franciscanus)

Largest urchin on the west coast; colors red or purple; predators include sea otters and sunflower stars.

Rock Jingle (Pododesmus macrochisma)

Thin-valved bivalve with the right valve cemented to the substrate; left valve has a dark muscle scar opposite the perforation and is otherwise polished inside; flesh is bright orange; dead shells make a jingling sound when struck.

Whitelined Chiton (Tonicella insignis)

8 plates with distinctive central triangles created by narrow, wavy white lines; end plates show pattern; girdle smooth and brown to green; length up to 6 cm.

Lined Chiton (Tonicella lineata)

8 smooth plates with zigzag pink, blue, red, and/or white lines; dislodged individuals roll into a ball to protect their undersides; feeds on microorganisms on algae surface and occasionally eats small crustaceans.

Gumboot Chiton

A species of chiton (mollusk) listed among chitons; not described in detail in notes.

Keyhole Limpet (Diodora aspera)

Rough-textured shell with a circular apex opening off-center; every fourth rib larger; shell gray-white with brownish-purple rays; can bite sea stars to make them move; omnivore feeding on bryozoans.

Whitecap Limpet (Acmaea mitra)

Usually white but can be tan or brownish; apex near the center; feeds on detritus, polychaete worms, chitons, bivalves, gastropods, sea urchins, sea stars, and tunicates.

Chinaman’s Hat (Calyptraea chinensis)

Limpet-like shell; apex with small nipple-shaped beaks, often slightly coiled; shell exterior white or yellow, interior pearly white; size up to 15 mm across and 5 mm high.

Dove Snail (Columbellidae)

Very small snails (1–2 cm) usually hidden under stones; well camouflaged; shells may contain tiny hermit crabs; thick shell with a narrow opening; long siphon.

Dotted Dove Snail (Euplica scripta)

1.5–2 cm; thick pale shell sometimes patterned with black and yellow markings; body plain with two tentacles and a long siphon.

Turtle Dove Snail (Pardalinops testudinaria)

1.5–2 cm; shell thick, white with net-like dark lines resembling a tortoise shell.

Lightning Dove Snail (Pictocolumbella ocellata)

1.5–2 cm; shell thick, dark with white or yellow zig-zag stripes; some forms are orange or red; lip of the shell opening thickened and often purplish on the inner side; long siphon.

Hairy Triton (Fusitriton oregonensis)

Largest intertidal snail in the Pacific Northwest; shell covered with brown spirally arranged bristles; nocturnal feeder on sea urchins, sea stars, chitons, and detritus; also preys on detritus, polychaete worms, bivalves, gastropods, sea urchins, sea stars, and tunicates; note: urchins attacked by hairy tritons can have tar-like scars.