crustaceans subphylum crustacea. typically have: 2 pairs of antennae 2 body sections (sometimes 3)...

CrustaceansSubphylum Crustacea

Typically have:2 Pairs of antennae2 body sections (sometimes 3)Chewing mouth parts called mandibles

Abdomen CephalothoraxCarapace

Antenna (2nd)

Cheliped with claws

Walking legs

Swimmerets

1st pair of antennae

Tail

(1st pair of legs)

(Fusion of head + thorax)

•Carapace covers the cephalothorax.•Protects the gills

Appendages:

Have different functions:Walking, Sensing the environment, Feeding, Defending against predators, Attracting mates

1st pair:Chelipeds – usedfor collectingand manupilatingfood (catch, pick up,crush, cut)

• Decapods – 5 pairs of legs (Deca = 10)

Fiddler crabs – Male crabs useits large claw toattract females

Some hermit crabs use the clawsto block the entrance of the shell

• 4 Pairs of walking legs

• Swimmerets -

Used for swimming and reproduction(males for transfer of sperm, females to holdEggs and young)

Male

Groups of Crustaceans:

1. Decapods: •Primarily live in saltwater environments.•5 Pairs of appendages•Fused body segments – Cephalothorax andabdomen

• Antennae – Have sensory hairs – used forsensing the environment. (Crayfish mainly)Other crustaceans – Swimming and Filter feeding

• Mandible – mouthpart used for biting andchewing

• Tail – paddle-like appendages fused with last segment

2. Barnacles:

• Sessile• Carapace similarto mollusk mantle, secretes a calcium shell• Feed by sweeping food into its mouth with feet

3. Isopods

• Seven pairs of legs• Most are marine and freshwater scavengers• Pill bugs and Wood lice (terrestrial)

4. Tongue worms:

• Parasitic• No eyes, mandibles or antennae.• Have lost most of their limbs

http://www.pbs.org/wgbh/nova/nature/tongue-parasite.html