Meet the arthropoda

Meet the Arthropods“Jointed Feet”

Kingdom Animalia!

Anatomy

• External skeleton made of calcium carbonate (Chitin)

• Jointed appendages

• Segmented body that is plankton-sized to a few meters long

• Bilateral symmetry

Anatomy cont.

• Open circulatory system – internal organs bathed in blood

• Nerve ganglia

• Compound eyes

• Rely on chemical and mechanical sensors (pheromones & antennae)

Reproduction

• External fertilization

• External development – frequently in pouches, sacks, on parents’ body

• Planktonic larvae

Phylum ArthropodaTwo Subphyla: A) Subphylum Chelicerata – Sea Spiders & Horseshoe Crabs

B) Subphylum Crustacea – Lobsters, Crabs, Shrimp, Barnacles

Habitat & Distribution

• Mostly benthic

• Mostly epifauna

• Worldwide

• This phylum contains

• the most species of any on earth

The only “attached” crustacean

Can you name them?

1. Subphylum Chelicerataa. Sea Spiders and b. Horseshoe Crabs

Like all Arthropods, they have no bones and grow by molting!

a. Class Pycnogonida(sea spiders-yipes!)

b. Class Merostomata

Horseshoe Crabs are True Blue Blooded

Creatures

We have ____________________ to make our blood red

Many crustaceans have hemocyanin, making their blood blue!

http://www.youtube.com/watch?v=e8KlAmtIu1E

Male Horseshoe

Crabs Have

Modified Front Legs That Look

Like Boxing

Gloves or Baseball Mitts to

Help Hold onto the Female During Mating

http://horseshoe-crabs.com/horseshoe-crabs-life-cycle-on-video/

2. Subphylum – Crustacea – Lobsters, Crabs, and Shrimp – oh my!

Crustacean Diversity

More Crustaceans:the sea insects

Scuds, Beach Hoppers, Beach Fleas, and Skeleton Shrimp:

The Amphipods

Still that familiar meroplanktonic

larvae we know and love! Special Name:

Zoea

Still No Skeleton – Molting Instead

The Smallest, Most Abundant Crustacean in the World’s

Oceans:

The Little Copepod

??What’s the largest planktonic Crustacean??

Are You “CooCoo” for Copepods?

What’s Going On Here????

http://www.youtube.com/watch?v=yMxY4c5SeIs

http://news.nationalgeographic.com/news/2006/09/060921-krill-video.html

http://library.thinkquest.org/J001418/what.html

Which Numbers Belong To Which Phyla?

(Try the rest for a good review before the unit test!)

References (on our class website)

• http://www.dnr.state.md.us/baygame/bbc_molting.asp

• http://www.k12.de.us/warner/structure.html