Friday, April 13, 2012

Phyla of Kingdom Animalia

This is just 10 of the Phyla belonging to the Animal Kingdom, I am putting these up here to help me study for my Biology test.  So I am listing the classification.  Click on each phylum to see characteristics, and more information and pictures!  Hope this is useful for someone - please leave a comment!
Click to enlarge  (Source)
Phylum Porifera - Sponges

  • Choanocytes (also called collar cells) - flagellated cells that trap and ingest food
  • Filter feeders - water goes in through a pore, up through the spongocoel (body cavity), and out the osculum (mouth) where food particles are trapped in the choanocytes
  • Parazoa - not true animals
  • No true tissues
  • Amoebocytes - Cells in the mesohyl ("middle matter") that transport nutrients to the sponge,  make spicules of CaCO3 (Calcium carbonate) for the skeleton, and can differentiate into any type of cell for the sponge
  • Cribrostatin - a chemical made by the sponge that has antibiotic properties (big in medical research)

Source prior to my extra labels
Phylum Cnidaria
  • Cnidocytes - stinging cells that insert a toxic string into prey
  • All carnivores
  • diploblastic
  • radial symmetry
  • single mouth/ anus
  • 2 body forms - medusa and polyp

  1. Class Hydrozoa ("water animal") - hydras
    • alternate between medusa and polyp forms
    1/2 cm long - Source
  2. Class Scyphozoa ("cup animal") - jellies
    • medusa form predominant
    Photo by me - Oregon Coast Aquarium, June 2012
  3. Class Cubozoa ("cube animal")- box jellies
    • medusa form only
      Box Jelly - source
    • most deadly venom in the world
    • painful sting will put a human into shock and they usually drown before reaching shore
    • Also called "sea wasps" and "marine stingers"
    • Each tentacle has about 5,000 stinging cells
    • Not triggered by touch, but by a chemical on the outside of their prey
    • Sea turtles are unaffected by the sting, and regularly eat the jellies  (Info from "Animal Society" blog)

  4. Class Anthezoa ("flower animal")- anemones, coral
    • polyp form only
    Giant Green Sea Anemone and orange Cup Coral
    Photo by me - Hatfield Marine Science Center, July 2012

Phylum Platyhelminthes - flatworms
  • Acoelomates
  • Flattened dorsoventrally
  1. Class Turbellara - planarians
    • Only non-parasitic flatworm
  1. Class Cestoda - tapeworms
    Click for Source
    • Head called scolex is equipped with suckers and hooks used to bore into intestinal wall in human host and take nutrients and just hang out there. 
    • Body segments called proglottids contain reproductive organs (hermaphroditic).  These segments, full of eggs, break off sometimes and are excreted in the feces where they can be spread if poor hygeine and sanitation don't interfere. 

  1.  Class Trematoda - flukes
  2. Class Monogenae
Phylum Nematoda - round worms
Phylum Rotifera
Phylum Annelida - segmented worms
  1. Class Clitellata - earthworms
    • Have clitella which houses the reproductive organs (hermaphroditic)
  1. Class Hirudinea - leeches
Phylum Echinodermata
  • deuterostomes
  • sessile, marine, bottom-dwelling
  • pentaradial symmetry
  • has water vascular system used for locomotion, feeding, and gas exchange
  1. Class Asteroidea - sea stars (Link to a post on specific sea stars and more on their anatomy) 
  2. Class Concentricycloidea - sea daisies
  3. Class Echinoidea - sand dollars & sea urchins
  4. Class Uphinoidea - brittle stars
  5. Class Crinoidea
  6. Class Holomuroidea - sea cucumbers 
Phylum Mollusca
  • Have 3 parts to their body
    • visceral mass
    • mantle (this is the part that secretes the shell)
    • muscular foot (modified into tentacles in cephalopods)
  1. Class Gastropoda - Snails
  2. Class Cephalopoda ("head foot") - Squid, Octopus
  3. Class Bivalvia - clams, oysters
  4. Class Polylacophora
Phylum Arthropoda
  1. Subphylum Hexapoda
    1. Class Insecta
  2. Subphylum Myriapoda
    1. Class Chilopoda - centipedes
    2. Class Diplopoda - millipedes
  3. Subphylum Crustacea
  4. Subphylum Trilobitomorpha - trilobites (extinct)
  5. Subphylum Cheliciformata
    1. Class Meristomata - horseshoe crabs
    2. Class Pycnogonida - sea spiders
    3. Class Arachnida
      1. Order Araneae - spiders
      2. Order Acari - mites & ticks
      3. Order Opiliones - harvestmen
      4. Order Scorpiones - scorpions  
Phylum Chordata
  • At some point in their development, all chordates have the following:
    • Notochord
    • Hollow dorsal nerve cord
    • Pharyngeal slits
    • Post-anal tail
  1. Subphylum Urochordata
  2. Subphylum Cephalochordata - lancelets
  3. Subphylum Vertebrata
    1. Class Agnatha - no idea
    2. Class Chondrichthys - cartilaginous fish
    3. Class Osteichthys - bony fish
    4. Class Amphibia - frogs, salamanders, etc.
    5. Class Reptilia - snakes, turtles, lizards, etc.
    6. Class Aves - birds
    7. Class Mammalia - you


  1. There's a mistake with the Scyphozoans. You said they're just medusoid but this is actually the most obvious stage, they do have a polyp stage too.

  2. Okay, good distinction. I updated it to say "medusa form predominantly" instead of "only", hopefully that makes it more accurate. Thank you for pointing that out!

  3. there are 7 classes under mollusc