1. Sub-phylum Crustacea
crabs, lobsters, shrimps, crayfish, barnacles, water fleas, fairy shrimps, copepods, isopods, & amphipods

2. Crustacean Diversity

3. General Features diversity (30,000 species)
fresh water & marine; terrestrial
sessile, commensal, & parasitic
biramous appendages
(2) pair of antennae
(1) pair of mandibles
(2) pair of maxillae
gills (usually)
tagmata (e.g. cephalothorax)

4. Form & Function: appendages: specialization feeding
swimmerets, uropods, & chelipeds
feeding
filter feeders, scavengers, parasites, & predators
respiration: diffusion & gills
excretion/osmoregulation:
green gland- excretes ammonia
circulation: open w/ hemocoel

5. Reproduction mostly dioecious direct or indirect development
planktonic larvae in many

6. Class Cirripedia barnacles sessile (adults); marine, filter feeders
respiration via the integument; no heart

7. Barnacles

8. Class Copapoda “cyclops”

9. Class Branchiopoda brine shrimp, fairy shrimp, and water fleas
characteristics: small size, filter feeders, gilled, & locomotory & zooplankton
Orders: Cladocera, Notostraca, & Anostraca
parthenogenesis
Daphnia used indicators of water quality

10. Order Notostraca- tadpole shrimps
nine species; one family
generally inhabit ephemeral lakes (playas)

11. Order Anostraca- fairy shrimps
fairy and brine shrimps (sea monkeys)
often inhabit ephemeral pools

12. Class Ostracoda- seed shrimps
6,650 species
54 genera and 420 freshwater spp.
fresh water, marine, & estuarine
consume mostly algae and organic detritus

13. Class Malacostraca largest and most diverse class
crabs, shrimps, crayfish, lobsters, isopods, etc.
marine, fresh water, and terrestrial
benthic; scavengers, predators

14. Order Isopoda pill bugs, sow bugs, or “rolley polly”
aquatic and terrestrial forms
Dorso-ventrally flattened body

15. Order Amphipoda sand fleas & scuds laterally compressed body
marine & fresh water

16. Order Decapoda largest order- > 10,000 species; 100 families
crabs, lobsters, shrimp, crayfish, and hermit crabs
marine, fresh water, & terrestrial
chelipeds- grasping appendage

17. Callinectes- blue crab

18. megalopa

19. Crayfish Morphology

21. Ecdysis (molting)
the Y-organ in the head of crustaceans controls ecdysis