Ch. 29
Spiders, scorpions, mites, ticks, & horseshoe crabs Have Chelicerae: a pair of appendages used to attack prey Subphyla Chelicerate
Have 4 pairs of “walking legs” Cephalothorax Carnivores Only consume liquid food Injects with enzymes that turn the prey’s tissues into liquid then they suck the liquid food into their stomach! Characteristics
Spiders (Arachnids) Chelicera = fangs Black widow & brown recluse = POISONOUS! Spinnerets appendages at the end of the abdomen that secrete sticky strands of silk Scorpions -Long, segmented abdomen that ends in a venomous stinger -Grasping pincers Groups
Mites and Ticks -Single, unsegmented body -Some cause irritating bites (Ticks) Horseshoe Crabs -Appeared on Earth about 400 million years ago -Blue blood! Groups Cont.
Ch. 29.2
Primarily marine Cephalothorax & an abdomen Mandibles for feeding 2 pairs of antennae Breathe by using gills Crustacean Characteristics
Isopods (Pill bugs) Sand fleas Must be close to water for reproduction! Terrestrial Crustaceans
Sessile (permanently attached to something) Crustaceans - barnacles Decapods = “Deca” + “pod” Shrimps, crayfish, crabs, & lobsters Cephalothroax 2 pairs of antenna used to “sense” Move through the water by contracting their abdominal muscles Aquatic Crustaceans