FREE ESSAY ON BRITTLE STAR

BRITTLE STAR

BRITTLE STAR
PHYLUM: Echinodermata
SPECIES: Ophioderma panamense
GEOGRAPHIC RANGE: From Peru and through Southern California
HABITAT: They have been observed in the mid and low tide zones, abundant on the sea floor
underneath rocks and in crevices and moving about tide pools and in available habitats in
southern California
NICHE: Omnivoire and filter feeder 
ADDITIONAL NOTES: Sometimes often called serpent starts due to their snake like
movements. The mouth is located on the underside of the central disc. The aboral disc and
arms are dark brown to black, and the disc is usually about 25mm. in diameter and the
arms near 180 in length. They have rounded bodies with five slender, flexible arms that
are easily broken off by any external force but are readily regenerated. Their food
consists of decaying matter and microscopic organisms. Their disc is covered with thick
granules, which obscure the radial shields, the disc margin is almost straight between
the arms, and the arm spines are short. Pg. 276
Specimen#2
BAT STAR
PHYLUM: Echinodermata
SPECIES: Patiria miniata
GEOGRAPHIC RANGE: It can be found from Alaska down through Mexico and is one of the most
common species in Southern California. Also common in Alamitos Bay, Cabrillo Bay, Corona
del Mar, Dana Point and Marina del Rey.
HABITAT: Found in tide pools in the low intertidal and subtidal zones hiding in protected
bays on rocks under rocks and in and around wharf pilings.
NICHE: Omnivore and scavenger
ADDITIONAL NOTES: With short triangular arms it shape it truly "star" shaped. Bat stars
range in a variety of colors from whitish to yellow or orange, red, purple - brown. The
aboral face is scaly. They use tubed feet for locomotion. Batstars range from 1 inch in
diameter to 6 inches. They don't have a heart. The Bat star is almost always accompanied
by a small commensal worm (Ophiodromus pugettensis), which lives in the ambulacral
grooves of its host. They feed by extending their stomachs over a great variety of plants
and animals, dead or alive. Usually having 5 arms and sometimes found with less or more.
Pg. 271
Specimen#3
SOFT SEA STAR
PHYLUM: Echinodermata
SPECIES: Astrometis sertulifera
GEOGRAPGIC RANGE: They can be found in all areas from Washington to Baja and have been
observed at Corona del Mar and La Jolla.
HABITAT: Around zone 4 and tide pools and protected rocky shores
NICHE: Omnivore and scavenger
ADDITIONAL NOTES: The arms numbers are 5 or 6 and the aboral surface is green to brown
with orange and blue spines. The skeleton is composed of isolated ossicles and the arm
span is almost 20 cm. . After the digested food is absorbed, the sea star pulls its
stomach back inside its body and moves on. The skeletal structure allows specimens to
readily shed their arms when handled. Pg.272
Specimen#4
SCALED WORM SHELL 
PHYLUM: Mollusca
SPECIES: Serpulorbis squamigerus
GEOGRAPHIC RANGE: The know distributional range has gone from central to Baja California
and around Corona del Mar.
HABITAT: They are abundant in all avalible habitats but are common on the under surfaces
of rocks in the low tide zone.
NICHE: Passive filter feeder
ADDITIONAL NOTES: They are normally in large colonies attached to rocks and pilings .
These animals are enclosed in twisted while calcareous tubes and are often mistaken for
polychaete annelids. Pg. 134
Specimen#5
SEA HARE
PHYLUM: Mollusca
SPECIES: Aplysia californica
GEOGRAPHIC RANGE: This is an abundant species on all seashores of California from Elkhorn
Slough to San Diego.
HABITAT: Often observed swimming in shallow water or stranded on the beaches at low tide.
They live in the intertidal zone and subtidally to about 40 feet.
NICHE: Grazing herbivores
ADDITIONAL NOTES: The body may grow to a length of 45 cm. And like the octopus, it ejects
a purple fluid when handled or disturbed. The body is brown, or mottled brown with almost
black. They eat various kinds of algae and eelgrass. Sea hares can eat 10 percent of
their weight a day. They have a complicated multi system stomached digestive system so
they can cope with such food. Sea hares are simultaneous hermaphrodites which means they
can act as male and female at the same time, however cannot fertilize their own eggs. A
single sea hare can lay millions of eggs at once, which look like yellowish, yellowish
green, to pick eggs that kind of resemble spaghetti. Pg.144
Specimen#6
GIANT KEYHOLE LIMPET
PHYLUM: Mollusca
SPECIES: Megathura cremulata
GEOGRAPHIC RANGE: It is known for distribution is from central to Baja California and
Montery bay and Alamitos Bay.
HABITAT: They have been observed in all available habitats but known to live in the low
intertidal zone and to depths of 110 feet on rocky substrates.
NICHE: Grazing herbivore
ADDITIONAL NOTES: They often attain the length of 10 cm. They have an oval shaped shell.
In color they are noted, as the mantle is deep unicolorous black, or a tan with dark
brown markings. Pg. 130
Specimen#7
PURPLE SEA URCHIN
PHYLUM: Echinodermata
SPECIES: Stronglylocentrotus purpuratus
GEOGRAPHIC RANGE: Known from Alaska to Southern California, and Cook's inlet, and Baja
California.
HABITAT: Depth range from the low intertidal zone to 10 m. usually found in tide pools
in-between rocks.
NICHE: Grazing herbivore; passive carnivore
ADDITIONAL NOTES: Diameter about 3 to about 8.5 cm. , short purple spines. The color
ranges from a light purple to a dark purple, They have a complex five-part jaw the
five-part jaw described by Aristotle and know as Aristotle's lantern. The jaw is located
on the oral surface. The three jawed pinching organs are called the pedicellariae which
they use to clean and defend themselves with and it contains a powerful toxin. Kind or
resembles the look of a pincushion. The spines and tube feet are what help the urchin to
gather food. They feed on algae. Pg.281
Specimen#8
STRIPPED SHORE CRAB
PHYLUM: Arthropoda
SPECIES: Pachygrapsus crassipes
GEOGRAPHIC RANGE: It is know to be anywhere from Oregon to Baja California.
HABITAT: It is omniprescent in tide pools and among rocks and jetties.
NICHE: Primarily a scavenger
ADDITIONAL NOTES: The carapace varies in color from green to red, and is distinguished
from other grapsids by the transverse stripes on the dorsum of the carapace. The carapace
of mature individuals is between 3 - 4 cm. in length. Like lobsters and shrimps, a female
crab carries her eggs under her abdomen for protection until they hatch into small
larvae. Crabs have a hard outer shell, or exoskeleton, that protects them from crashing
waves as well as from biting fish. They are very agile and can scamper rapidly over the
sharp, jagged rocks on their nimble feet. The tips of their walking legs have short stiff
spines that grab on to the rock and prevent wearing away of the legs on the rough
surface. Pg. 240
Specimen#9
CONSPICUOUS CHITON
PHYLUM: Mollusca
SPECIES: Stenoplax conspicua
GEOGRAPHICAL RANGE: From Southern California and especially in Dana Point.
HABITAT: Found on the underside of large rocks during the daylight hours. Found in the
low tide zone.
NICHE: Grazing Herbivores
ADDITIONAL NOTES: They have an eight part calcareous shell that is embedded in a leathery
skin. They are nocturnal. It is negatively phototaxic and as a consequence will be found
under rocks. Their color is a gray green with a pinkish dorsal and color of the girdle is
gray green. Chitons are slow moving, but are not immobile. A chiton can roll itself up
into a ball, exposing only the hard shell, when it feels threatened. Chitons feed upon
seaweed and algae. Chitons clamp themselves to rocks using their foot and their girdle
(the part of the shell that encircles the chiton & 8 plates) to withstand weather & wave
action. It crawls by means of muscular undulations of the foot. The mouth, located in
front of the foot, contains a toothed scraping organ, the radula. Mature individuals are
almost 10 cm. in length. Pg.124
Specimen#10
CALIFORNIA SPINEY LOBSTER
PHYLUM: Arthropoda
SPECIES: Panulirus interruptus
GEOGRAPHICAL RANGES: San Luis Obispo, California to Rosalia bay and Baja California
HABITAT: Depths range from 10 to 60 m. Tide pools but usually small if seen there.
NICHE: Scavengers
ADDITIONAL NOTES: Spines cover their long antennae and the front of their bodies. They
lack having the large claw characteristics of the Atlantic lobster. Mostly nocturnal and
foraging at the bottom at night. Can reach the length to about 60 cm. and can weigh 25
pounds. Mature individuals can be observed in fish markets and occasionally a specimen is
observed in the water at times of the lowest tide. 45 species of spiny lobsters of the
Palinuridae family. The heavily armored antennae can inflict a tearing wound when the
lobster thrashes them whip-like against an opponent. Unlike the American lobster, spiny
lobsters seem to enjoy each other's company and often share their dens. They may warn
other lobsters of danger with loud rasping sounds they make by rubbing the base of their
antennae against serrated ridges below their eyes. Hundreds, sometimes thousands, of
spiny lobsters form columns of as many as 60 lobsters to migrate en masse, often after a
storm.