Arthropoda Chelicerata(Eight- legged Arthropods)

By Sydney Furth & Brenna Banderob

5/19/09pr. 3

Anoplodactylus evansi

(no common name)

Classification

• Subphylum breaks into classes:

-Arachnida (arachnids)

-Merostomata (horseshoe

crabs)

-Pycnogonida (sea spiders)

Limulus

polyphemus

Horseshoe crab

Physical Features

• Exoskeleton• Jointed limbs• Segmented body• Well developed

nervous system• Eight legs• No antennae• No distinct head

Pseudopallene ambigua

Yellow Pycnogonid

Reproduction

• Sexual reproduction• Produces eggs

Spider eggs

Feeding & Digestive System

• Digestive system divided into 3 parts

-foregut

-midgut

-hindgut• carnivores• Sometimes eat other

arthropods

Circulatory System

• Heart= long thin tube• Blood travels through

open passages• Pale blood cells

- bluish• If skin broken- blood

drains quickly

Respiratory System• 2 breathing organs

-tracheae -small tubes that

carry air through body

-book lungs -cavities in

the abdomin -air enters

from slits on either side

environment

• land arthropods can be found any where on land

• Water for horseshoe crabs & sea spiders (obviously)

-fresh and salt water

Spider web

Human Interactions

• Most people go EEEKK at the sight of 8-legged arthropods

• Many spider bites can cause problems, such as death

• Scorpion & spider venom is used to make powerful medicines & vaccines

A bite from this caused

this

Loxosceles reclusa Brown recluse

spider

Unique Features• Cold blooded• Most spiders have

week vision• Horseshoe crabs (who

live in water) come ashore In large numbers to lay eggs

• Horseshoe crabs swim upside-down

Centruroides vittatusstriped scorpion

Examples

• Tarantula movie

Works Cited• Myers, P. 2001. Chelicerata. Animal Diversity

Web. May 19, 2009. <http://animaldiversity. umnz.umich.edu/site/accounts/information /Chelicerata.html>

• Holt, Rinehart, Winston. Animals. Austin, Texas: Harcourt Classroom Education Co., 2002

• The Invertebrate Animals. May 20, 2009. <http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/I/invertabrates.html>

• Eisen, Stan. Arthropoda chericerata. May 21, 09.

<http://www.cbu.edu/~seisen/Arthropoda/sld014.htm>

• Spiders. May 21,09. <http://www.greensmith s.com/spiders.html>

• Thompson, ken. The bumble bee. May 20, 09. <http://www.bioteams.com/2006/04/21/the_social_networks.html>