Phylum Arthropoda Notes

sponge crab

a pregnant crab (holding fertilized eggs on her abdomen)

copepods

a crustacean that is only 1 to 2 mm long, has a single red eye, and a pair of long antennae

hermit crab

more closely related to a lobster than a crab, lives in a snail shell, and finds larger shells to live in as it grows bigger

decapods

the largest crustaceans having 10 legs, and include shrimps, crabs, and lobsters

molt

to shed the exoskeleton that is now too small for the growing arthropod

krill

shrimp-like crustaceans that live in polar regions are an important food source for whales and penguins

isopods

small crustaceans that have a flat dorsal surface. some species are commonly known as fish lice as they are parasites of fish

horseshoe crab

living fossils that have blue blood, a large telson, and are more closely related to spiders than crabs

amphipods

these small crustaceans have curved bodies, compressed sides and are commonly known as sand fleas or sand hoppers

barnacles

these crustaceans lie on their backs and their bodies are enclosed in thick plates; they have filter feeding feathery legs that project out of the water

exoskeleton

the protective rigid, outer shell of an arthropod, made of chitin and calcium carbonate

compound eyes

a bundle of visual units, each unit forming a portion of the total image. allows for the ability to see images, albeit with poor resolution (blurry)

cirri

the feathery filter feeding legs of a barnacle. they sweep the water and filter out food particles

sea spiders

a marine arthropod that is not a crustacean but more closely related to spider. have small bodies but extremely long legs.

arthropoda

this latin term means “jointed foot”

male

the last pair of swimmerets on a ______ crayfish are long and rigid

chelipeds

the first pair of legs with the largest claws

carapace

the saddle shaped part of the exoskeleton that covers the cephalothorax

telson

the central part of the tail fan

walking legs

these 4 pairs of legs are used for walking

female

the last pair of swimmerets on a ________ crayfish are soft and feathery

abdomen

the posterior region of a crayfish, behind the cephalothorax. it contains the swimmerets and the tailfan

cephalothorax

the fused head and thorax of a crayfish

swimmerets

these appendages are located on the ventral side of the abdomen and used primarily to swim but also allows a female crayfish to hold her fertilized eggs

tailfan

the posterior part of the abdomen. it contains the uropods and telson and is used with the abdomen to move the crayfish backwards