1. MenuPreviousNext 6 - 1 Crustaceans - Underwater Arthropods Crustaceans – Underwater Arthropods Chapter 6 Pages 6-29 to 6-34

2. MenuPreviousNext 6 - 2 Characteristics of Crustaceans Crustaceans – Underwater Arthropods Chapter 6 Pages 6-29 to 6-30

3. MenuPreviousNext 6 - 3 Characteristics of Crustaceans nPhylum Arthropoda is the most numerous of multicellular animal phyla.  There are several intermediate classifications.  There may be many more than one million arthropod species. Some estimate 20 million.  Characteristics: segmented bodies, jointed legs, a chitinous exoskeleton. Crustaceans – Underwater Arthropods Chapter 6 Pages 6-29 to 6-30

4. MenuPreviousNext 6 - 4 Characteristics of Crustaceans nSuperclass Crustacea – an intermediate classification. Characteristics include:  A pair of appendages on each body segment.  Two pairs of antennae.  Mandibles for chewing.  Teardrop-shaped larvae.  Exoskeletons are shed as they grow. Crustaceans – Underwater Arthropods Chapter 6 Pagse 6-29 to 6-30

5. MenuPreviousNext 6 - 5 Special Attributes of Class Cirripedia nBarnacles unique lifestyle sets them apart into class Cirripedia.  Life begins as free-swimming larvae like other crustaceans.  When the larva finds a surface on which to live (rocks, boats, etc.) it fuses itself in place “upside down.”  The exoskeleton forms the carapace (hard shell) the barnacle can withdraw into for protection. Crustaceans – Underwater Arthropods Chapter 6 Pages 6-30 to 6-31

6. MenuPreviousNext 6 - 6 Special Attributes of Class Cirripedia Barnacle Anatomy Crustaceans – Underwater Arthropods Chapter 6 Pages 6-30 to 6-31

7. MenuPreviousNext 6 - 7 Special Attributes of Copepods nCopepods play a central role in the ocean food webs.  They are important primary and secondary consumers of phytoplankton and zooplankton.  Relatively few larger animals can consume the tiniest plankton, but many can eat the larger copepods. Fish, krill, and giant plankton feeders, including whale sharks, baleen whales, and manta rays all eat copepods.  Copepods are important to ocean food webs because they link the tiny primary producers and consumers to the large animals higher up the web. Crustaceans – Underwater Arthropods Chapter 6 Pages 6-31 to 6-32

8. MenuPreviousNext 6 - 8 Special Attributes of Decapods and Krill nClass Malacostraca includes two orders of interest due to their roles as food for humans and food for nature. nOrder Decapoda: lobsters, shrimps, and crabs  Have 10 functional legs (deca meaning ten and poda meaning foot).  Have claws and an extended carapace that encloses the gills. nBecause humans eat these shellfish, they are an important food source and resource on which the fishing industry relies. Crustaceans – Underwater Arthropods Chapter 6 Pages 6-32 to 6-34

9. MenuPreviousNext 6 - 9 Special Attributes of Decapods and Krill nOrder Euphausiacea: krill  Krill are small plankton crustaceans consumed by larger predators.  In subpolar food webs, they are vital. Whales, seals, sea birds, and penguins only survive in highly productive waters. Much of the food web above krill depends on it for life. Crustaceans – Underwater Arthropods Chapter 6 Pages 6-32 to 6-34