INTRODUCING the ARTHROPOD
CRUSTACEANS with species from southern California ROBERT PERRY Malibu High School & UCLA Ocean GLOBE
Pleuroncodes planipes
ABOUT THE COVER PHOTOGRAPH:
The pelagic red crab, Pleuroncodes planipes
Pelagic red crabs are occasional planktonic visitors from the south.
Pleuroncodes larva Pleuroncodes planipes
DISTRIBUTION OF Pleuroncodes planipes
They are often so abundant that they completely fill our trawls.
Pleuroncodes planipes
Pleuroncodes planipes
Commercial fishing for Pleuroncodes sp.
Phylum
ARTHROPODA Over 923,000 different species !!!!!!!! Arthropods have an external skeleton (exoskeleton) that covers the entire outer surface of the body. “Arthro” “pod” means ‘jointed-legs.’ Must shed exoskeleton to grow.
eukaryotes
porifera
ANIMALS
THE ANIMAL KINGDOM
cnidaria platyhelminthes
bryozoa arthropoda mollusca
annelida echinodermata
cho r
d at
a Animal cladogram based on DNA sequencing From National Museum of Natural History http://www.amnh.org/exhibitions/hall_tour/spectrum/graphics/cladogram.gif
Phylum Arthropoda. P h y lu m ARTHRO PO DA IN S E C T S
The most diverse group of animals on earth, but, alas! not in the ocean.
S P ID E R S
Don’t live in the ocean.
“Arthro” “pod” means ‘jointed-legs.’
Arthropods have an external skeleton that covers the entire outer surface of the body.
C la s s CRUSTACEA
Crabs, lobsters, barnacles, copepods, etc.
Class
CRUSTACEA
From the Latin, Crustaceus, meaning soft (refers to soft shell after moulting).
Mostly aquatic arthropods with 2 pairs of post-oral antennae.
Cancer antennarius
Phylum Arthropoda:
Class Crustacea
Benthic sand crab Benthic isopod
Planktonic copepod shrimp
Benthic barnacles
CRUSTACEANS MOULT THEIR SHELLS TO GROW
Panulirus interruptus
Graph - R. Perry
BRANCHIOPODA
Animation from Microscopy UK – Water Fleas http://www.microscopy-uk.org.uk/mag/artjun99/wflea.html
Branchiopod cladocerans are found in freshwater and seawater. They are often called “water fleas.� The most common genera we find are Podon and Evadne.
Evadne sp.
Cladocerans brood their young under their carapace until they are mature.
Arthropoda/Crustacea:
CIRRIPEDIA Cirri = tiny fingerlike hairs Pedia = on their legs
Barnacles are like tiny shrimps lying on their backs inside an outer shell, kicking food into their mouths. Balanus spp.
Balanus spp.
Balanus tintinabulum and Tetraclita squamosa attached to wooden pier pilings, on the Santa Monica Pier.
Human consumption of barnacles - “Seaparrot.”
Barnacle eggs hatch as planktonic nauplius larvae. All crustaceans undergo a nauplius stage as their first stage of development.
Pollicipes polymerus
“Gooseneck� barnacles, Pollicipes polymerus, seen close-up Extending their legs to feed. Attached to the Santa Monica Pier.
Arthropoda/Crustacea:
COPEPODA Copepod ( Kope = Greek for "oar" Podos = Greek for "foot")
- Images and text from the Smithsonian Institute http://www.nmnh.si.edu/iz/copepod/
3D computer generated model. http://jaffeweb.ucsd.edu/pages/celeste/Stills/StillBottomOblique.jpg
After Marshall & Orr (1972)
eye Primary antenna
maxilla
Thoracic limb
abdomen
Calanoid copepod – right lateral view
Tiny planktonic copepods are the most abundant animal in the sea. Their biomass exceeds that of all other animals combined.
Copepods swim by moving their primary antennae down, similar to the breast stroke.
Calanoid copepod – dorsal view
Water flow fields created by a calanoid copepod. Note the strongest fields are around the mouth. These are the feeding currents.
Mouth region of Euchaeta, a large carnivorous copepod that rakes in smaller species of copepods.
Cyclopoid copepod females lateral brood view their eggs on their abdomen. dorsal view
Some copepods are parasitic on fish and mammals.
dorsal view Robert Perry
Smithsonian Institute
MALACOSTRACA
Diver with “spider crab” Loxorhyncus grandis
The author, on a night dive with the “sheep crab” Loxorhynchus grandis.
Loxorhyncus grandis
Human consumption of Loxorhynchus grandis
Another species, Loxorhynchus crispatus, “decorates” is own shell with sessile benthic organisms. This species has tiny microscopic hooks that project from its shell. The crab “hooks” bits of seaweed and other debris all over its dorsal surface. In this photograph, bryozoan colonies and a red anemone have been attached.
Loxorhyncus crispatus
Unfortunate L. grandis entangled in a gill net – Channel Islands National Marine Sanctuary, Anacapa Island. This is known as “by-catch.”
Loxorhyncus grandis
Cancer magister
Many malacostracans are good to eat ! Cancer magister, San Francisco Fisherman’s Wharf.
Human consumption of Cancer anternnarius etc.
Cancer antennarius
CARAPACE ON CEPHALOTHORAX REGION
ABDOMEN (PLEON)
PRIMARY ANTENNA EYE
SECONDARY ANTENNA
THORACIC LIMB 1. CHELA
MANDIBLE
MOUTH MAXILLA
TL 2.
TL 3.
Cancer antennarius
ABDOMEN (PLEON)
TL 4. TL 5.
Crab females brood thousands of eggs under their abdomen.
Cancer antennarius
Crab zoea larvae have spikes on their nose and head.
DEVELOPMENT IN ANOTHER DECAPOD: Blepharipoda occidentalis
VENTRAL SIDE OF FEMALE WITH EGG MASS
CLOSE VIEW OF EGG MASS
CLOSER VIEW OF EGG MASS AT AN EARLY STAGE OF DEVELOPMENT
CLOSER VIEW OF EGG MASS AT A LATER STAGE OF DEVELOPMENT
EXTREME VIEW OF EGG MASS AT AN EARLY STAGE OF DEVELOPMENT
EXTREME VIEW OF EGG MASS AT A LATER STAGE OF DEVELOPMENT
CLOSER VIEW OF EGG MASS AT A LATER STAGE OF DEVELOPMENT - BACKLIGHT
VIEW OF NEWLY HATCHED MASSES OF ZOEA LARVAE
VIEW OF NEWLY HATCHED ZOEA LARVAE AND LATE EMBRYONIC EGG STAGE
ZOEA
LATE EMBRYO
ZOEA LARVAE
ZOEA LARVAE (COMPOSITE IMAGE OF FRONT AND BACK LIGHTING)
CALIFORNIA SPINY LOBSTER
Many crustaceans are good to eat. The california spiny lobster, Panulirus interruptus, was once so abundant that these men captured them in the tide pools. Panulirus interruptus
The California spiny lobster, Panulirus interruptus, at home on a rocky subtidal reef.
Panulirus interruptus
Note the two pairs of pre-oral antennae !
In the spring, males transfer a gummy sperm packet to the underside of the female.
Panulirus interruptus
During the summer, when lobster season is closed, the females use the sperm packet to fertilize thousands of orange eggs, which are kept under her pleopods.
Panulirus interruptus
The eggs hatch out as planktonic phyllosoma larvae and drift away.
x40
3 mm
Panulirus interruptus
Licensed lobster boats set traps in rocky subtidal areas. Their traps are marked by floating buoys.
On the bottom, the lobster traps provide a one-way entrance.
Panulirus interruptus
Human consumption of lobster: WEST COAST
Simple, tastey lobster tails full of delicious meat.
EAST COAST
Messy, tedious, picking and cracking and sucking to get the meat.
Human consumption of Panulirus interruptus:
Panulirus interruptus
THE END Please direct all comments to perry@smmusd.org