 |
Pachygrapsus
crassipes Randall,
1839 Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Brachyura, Family Grapsidae Lined shore crab; carapace trapezoidal with 2 antero-lateral teeth on each side; dark green-black with red or purple highlights on appendages; broken transverse lines across top of carapace, 40-45 mm across. Abundant, but fast, cryptic & pugnacious; high to mid-intertidal zone, exposed & protected outer coast; feeds on algal films & scavenges. Geogr. Range: central Oregon to BajaSynonyms: Similar species: Hemigrapsus nudus has purple spots on chelae. | back to spp. list | more info | refs. | SeaNet home | |
 |
Hemigrapsus nudus
(Dana, 1851) Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Brachyura, Family Varunidae Purple shore crab; carapace a rounded square lacking horizontal lines, 35-50 mm across; purple, yellow- green, red-brown; usually with purple spots on chelae. Moderately common; more sluggish & less aggressive than Pachygrapsus; under rocks & among seaweeds; mid- to low intertidal zone, protected outer coast. Geogr. Range: Alaska to Baja (uncommon south of Morro BaySynonyms: Similar species: Pachygrapsus crassipes has horizontal lines on carapace & no spots on claws. | back to spp. list | more info | refs. | SeaNet home | |
 |
Cancer
antennarius
Stimpson, 1856 Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Brachyura, Family Cancridae Adults 15-18 cm across reddish-brown carapace; claws tipped with black; underside of body with red spots; juvenile carapace usually covered with hairs. Common, but cryptic under rocks and algae; low intertidal zone & subtidal, protected outer coast. Preys on hard-shelled prey (snails, clams, etc). Geogr. Range: British Columbia to Cabo San Lucas, BajaSynonyms: Similar species: Cancer productus is also reddish with black-tipped claws, but it lacks red spots on ventral side & the teeth on its carapace are broader & rounder; its juveniles often have a striking zebra-stripe color pattern that is lacking in C. antennarius. | back to spp. list | more info | refs. | SeaNet home | |
 |
Petrolisthes
cinctipes (Randall,
1840) Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Anomura, Family Porcellanidae Porcelain crab; 3 pr. walking legs with 1 pr. broad flat claws; carapace square, antennae dk. red; carapace to 24 mm, lacks hairs; color light brown to dk. brown; mouth parts bright red; red-orange spot at base of dactyl on claws; readily autotomizes appendages when disturbed. Abundant under rocks, high to mid-intertidal zones; protected outer coast. Suspension feeder. Geogr. Range: British Columbia to Santa Barbara, Calif.Synonyms: Similar species: Petrolisthes eriomerus & P. manimaculus have more slender claws & occur lower on the shore | back to spp. list | more info | refs. | SeaNet home | |
 |
Pagurus samuelis
(Stimpson, 1857) Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Anomura, Family Paguridae Hermit crab; antennae red & unbanded; irregular patches of blue on tips of legs; small juveniles often with white bands on legs; carapace to 19 mm; dark olive green. Most common hermit crab in tidepools; high to mid-intertidal zones; protected outer coast; prefers turban snail shells. Geogr. Range: Vancouver Island to BajaSynonyms: Similar species: Pagurus granosimanus has blue or white bumps on carapace & claws; numerous spp. of hermit crabs occur in tidepools. | back to spp. list | more info | refs. | SeaNet home | |
 |
Pagurus
granosimanus (Stimpson,
1859) Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Eucarida, Order Decapoda, Infraorder Anomura, Family Paguridae Hermit crab; antennae red-orange, unbanded; dark olive green with blue or white wart-like granules, especially on chelae & walking legs. Common, in tidepools, lower mid- to low intertidal & subtidal. Geogr. Range: Aleutian Islands, Alaska to BajaSynonyms: Similar species: Pagurus samuelis lacks blue or white granules on legs & claws; numerous spp. of hermit crabs occur in tidepools. | back to spp. list | more info | refs. | SeaNet home | |
 |
Cirolana
harfordi (Lockinton,
1877) Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Peracarida, Order Isopoda, Family Cirolanidae Isopod; oval, dorsoventrally-compressed body to 20 mm (most closer to 10 mm), pale gray or tan to black. Abundant, under rocks resting in sand or gravel; also in mussel beds; mid-intertidal zone, exposed & protected outer coast; voracious scavenger / predator. Geogr. Range: British Columbia to BajaSynonyms: Similar species: many other spp. of isopods occur on rocky shores. Image: juvenile Chlorostoma funebralis (middle rt.) | back to spp. list | more info | refs. | SeaNet home | |
 |
Ligia
occidentalis Dana,
1853 Phylum Arthropoda, Subph. Crustacea, Class Malacostraca, Subcl. Eumalacostraca, Superorder Peracarida, Order Isopoda, Family Ligiidae High-shore isopod; dorsoventally-compressed body to 25 mm; elongate uropods (specimen in photo missing 1 uropod). Common, under stones & in crevices; high intertidal zone well above the highest tides; spends most of time out of the water, returning only to wet its gills; extremely quick and agile. Geogr. Range: Sonoma County to Central AmericaSynonyms: Similar species: many other spp. of isopods occur on rocky shores. | back to spp. list | more info | refs. | SeaNet home | |
All images copyright James Watanabe unless otherwise indicated