Most widespread and abundant phylum of animals ARTHROPODS Most widespread and abundant phylum of animals 3 out of 4 animals are arthropods!

Classification Two major subphylums that marine arthropods are found in Subphylum CRUSTACEA Suphlyum CHELICERATA

GENERAL CHARACTERISTICS Exoskeleton made of chitin Segmented body Specialized appendages Sensory, feeding, movement Mandible- Special mouthparts in arthropods for chewing food Can regenerate appendages Gills to obtain oxygen from sea water

Well developed organ systems Open CS Well developed NS Complete DT GENERAL CHARACTERISTICS cont… Well developed organ systems Open CS Well developed NS Complete DT Reproduction-separate sexes and sperm is usually directly transferred to the female

Arthropods molt-shed their shell & grow a new one as they grow. http://www.dnr.state.md.us/baygame/molt2.jpg

Crustaceans Largest marine group Biramous appendages- legs branch off into 2 parts www.obs-vlfr.fr/.../copepods_guide/help.html

http://1.bp.blogspot.com/_e-mPA_6ZQyg/RvXkxRqUXVI/AAAAAAAAECM/xZ4BQgLV00w/s400/crustaceans.gif

The swimming legs of crustaceans are called swimmerets. http://www.glf.dfo-mpo.gc.ca/photos/images/white_lobster.jpg http://home.earthlink.net/~wweinkle/crabinternal2.jpg

Crustacean Habitats Mostly a marine group Insects of the sea Important members of benthic communities dark nooks (under rocks and crevices)

Detritivores (scavengers) Parasites Carnivorous CRUSTACEAN FEEDING Detritivores (scavengers) Parasites Carnivorous

Maxillipeds- special appendages in crustaceans (arms)for cutting and manipulating food http://atiniui.nhm.org/glossary/image.mason?imageID=19&size=300

Serial homology of appendages as seen in a stomatopod Serial homology of appendages as seen in a stomatopod. From left to right appendages are: antennule, antenna, mandible, first and second maxillae, first through fifth maxillipeds, 3 walking legs, 5 pleopods with pinkish gills, and uropod. http://images.google.com/imgres?imgurl=http://www.ucmp.berkeley.edu/arthropoda/crustacea/images/serial_appendages_sm.jpg&imgrefurl=http://www.ucmp.berkeley.edu/arthropoda/crustacea/appendages.html&usg=__iENbe_1_g_87lJzQN9pPDvBhj28=&h=200&w=500&sz=21&hl=en&start=7&tbnid=fl05qzSmOmxIPM:&tbnh=52&tbnw=130&prev=/images%3Fq%3Dmandible%2Bmaxilloped%2Bcrustacean%26gbv%3D2%26hl%3Den%26safe%3Dactive

CLASS MAXILLIPODA SMALL CRUSTACEANS like:

-may be the most common animal Copepods -may be the most common animal -important as zooplankton and food source for larger consumers http://mysciencefairproject.net/images/macrocyclops1_zexs.jpg

Parasitic copepod in mako gills http://carlsafina.wordpress.com/2007/07/05/welcome-to-the-hotel-californshark-2/

Many copepods are parasites of fish. http://www.darwinsgalapagos.com/animals/parasitic_copepod_sm.jpg

usually attached to surfaces (very particular about where they attach) Barnacles filter feeders usually attached to surfaces (very particular about where they attach) http://shiftingbaselines.org/blog/Barnacle.jpg

Class Malacostraca Larger crustaceans like…..

Krill Swarming, shrimp like animals found in all oceans Important in polar waters as food source for whales, penguins, seals Declines in krill populations are a concern for food web Linked to melting sea ice Linked to commercial krill fishery http://www.mar-eco.no/learning-zone/__data/page/93/Krill3.jpg

Most diverse and widespread small crustacean Order Amphipoda Tiny and shrimp-like Most diverse and widespread small crustacean Found in almost all damp environments Some are parasitic http://www.reef-eden.net/Amphipod1.jpg

Found on ocean floor from shallow to deep ocean Isopods flat from top to bottom Found on ocean floor from shallow to deep ocean http://blogs.nature.com/news/thegreatbeyond/giantisopod.jpg http://oceanexplorer.noaa.gov/explorations/04etta/background/isopods/media/synidotea_laevidorsalis.html

1st pair of legs for defense and getting food Decapods 1st pair of legs for defense and getting food Well developed carapace (outer shell) Can feel pain http://www.flmnh.ufl.edu/fish/gallery/descript/alligatorgar/bluecrab.JPG

compound eyes on stalks well developed sense of smell scavengers Lobsters large front claws -walking decapod compound eyes on stalks well developed sense of smell scavengers www.metro.co.uk

Lobsters may live to be 100 years old. http://www.cryptomundo.com/cryptozoo-news/giant-crayfish/

Female lobster holds eggs in her swimmerets. www.helgoland-lobster.de/indexe.html http://www.penobscoteast.org/images/lobster_eggs.jpg

Shrimp Diverse group of crustaceans Found in salt and freshwater Important food source for humans and marine life http://www.dfw.state.or.us/MRP/shellfish/commercial/largeimages/shrimp_headroe_eggs_large_ODFW.jpg

Shrimp are scavengers that feed on small pieces of dead plant and animal material (omnivores). stilton.tnw.utwente.nl/shrimp/shrimp1.jpg

CRABS Small abdomen that is tucked under thorax Most scavengers Live along rocky shoreline Some terrestrial (return to sea only to release eggs)

Mouth Swimming legs

Female crab holds eggs in her abdomen. http://cache.daylife.com/imageserve/00DRgZO7DQehn/610x.jpg

The 2 grasping claws of crabs are also called pincers or chelipeds. http://www.animalwebguide.com/Fiddler-Crab-1.jpg

Wider abdomen is female Sexing crabs Narrow abdomen is male Wider abdomen is female http://hawaii.gov/dlnr/dar/images/Samcrabs.jpg

Class Merostomata horseshoe crabs Book gills for breathing Mouth parts for piercing called chelicerae living fossil http://horseshoe-crabs.com/horseshoe-crab-book-gills.html http://beachchairscientist.files.wordpress.com/2008/07/horseshoe-crab.jpg

Blood is used to test for bacteria in pharmaceuticals Critical food source for migrating shore birds like the red knot Conservation efforts to ban use of crab meat as bait

Pycnogonida Found worldwide Most are small and deep water Use a "proboscis " to pierce and suck liquid from seaweeds and various invertebrates.

The Japanese spider crab is the largest arthropod http://huynhwinsituation.files.wordpress.com/2009/03/japanese-spider-crab.jpg

Fiddler Crabs