Subphylum Mandibulata

1
Subphylum Mandibulata

• Order Decapoda

2
Order Decapoda

• Large carapace that covers the thorax on the
  dorsal and sides
• Segmentation is only visible from the ventral
  surface

3
Shrimps

• Active and efficient swimmers pleopods are
  well-developed for swimming
• Uropods and telson can be used for swimming
• Pincers are on first three pairs of thoracic legs
• Commercially important shrimps belong to the
  families Penaeidae and Sicyoniidae

Rock Shrimp
4
Lobsters and Burrowing Shrimp

• Contains the American and spiny lobster which are
  not closely related
• Both are large and capable of reaching two feet
  in length
• Large abdomen (muscular) well-developed uropod
• American lobster has a smooth carapace
• Closely related to ghost and mud shrimps
  (crawfish)

5
Anomuran crabs
6
Brachyuran Crabs

• True crabs, greatly reduced abdomen which is
  flexed to lie in a groove beneath the thorax
• Cephalothorax is dorsoventrally flattened and
  antennae are short
• Have one pair of pincers
• Swimmers have thinner shells and paddled
  swimmerets
• Sponge and shellback crabs cover themselves with
  tunicates, sponges etc.

7
Brachyuran Crabs
8
Brachyuran Crabs

• Portunid crabs the most common and best know

9
Blue Crab Life Cycle