most widespread and abundant phylum of animals 3 out of 4 animals are arthropods!
TRANSCRIPT
• Most widespread and abundant phylum of animals
• 3 out of 4 animals are arthropods!
Two major subphylums that marine arthropods are found in
Subphylum CRUSTACEA
Suphlyum CHELICERATA
Classification
CHARACTERISTICS
• Exoskeleton made of chitin
• Segmented body
• Appendages specialized –Sensory, feeding, movement
–Can regenerate appendages
• Gills to obtain oxygen from sea water
Well developed organ systems –Open CS–Well developed NS –Complete DT
• Reproduction-separate sexes and sperm is usually directly transferred to the female
GENERAL CHARACTERISTICS cont…
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
Crustaceans molt-shed their shell & grow a new one as they grow.
http://www.dnr.state.md.us/baygame/molt2.jpg
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
Mostly a marine group
Insects of the sea
Important members of benthic communities
dark nooks (under rocks and crevices)
Crustacean Habitats
Detritivores (scavengers)
Parasites
Carnivorous
CRUSTACEAN FEEDING
Maxilopeds- special appendages (arms)for cutting and manipulating food
Mandible- Special mouthparts for chewing food
• 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
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.
-may be the most common animal
-important as zooplankton
and food source for larger consumers
Copepods
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
• filter feeders
• usually attached to surfaces (very particular about where they attach)
Barnacles
http://shiftingbaselines.org/blog/Barnacle.jpg
Tiny and shrimp-like
Most diverse and widespread small crustacean
Amphipods
http://www.reef-eden.net/Amphipod1.jpg
• flat from top to bottom
• successful on land too
Isopods
http://blogs.nature.com/news/thegreatbeyond/giantisopod.jpg http://oceanexplorer.noaa.gov/explorations/04etta/background/isopods/media/synidotea_laevidorsalis.html
• shrimp-like
• important in polar waters as food source for whales, penguins, seals
Krill
http://www.mar-eco.no/learning-zone/__data/page/93/Krill3.jpg
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
Lobsters -large front claws - 4 pairs of jointed walking legs-compound eyes on stalks
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.
http://www.penobscoteast.org/images/lobster_eggs.jpg
www.helgoland-lobster.de/indexe.html
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)
Swimming legs
Mouth
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
Narrow abdomen is maleWider 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://beachchairscientist.files.wordpress.com/2008/07/horseshoe-crab.jpghttp://horseshoe-crabs.com/horseshoe-crab-book-gills.html
• 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