Journal. Differentiate between pleopods and periopods in a crayfish. Please turn in Crayfish Dissection Lab if you haven’t already done so. Journal. Choose one of the questions below to answer: How are hunting spiders different from web spinning spiders?
a. Chelicerae- first pair, pincer-like, feeding/fangs
b. Pedipalps- second pair, sensing, feeding, reproduction
3. No antennae
4. 8 walking legs
7. Dioecious- male fertilizes eggs as female sheds them into a shallow hole. No brooding occurs.
Horseshoe crab vision
EX: Spiders, mites, ticks, scorpions
** Water conservation is a major concern for many terrestrial animals. Most wastes excreted in solid form to prevent water loss.
4. 6-8 Simple eyes- sense light & movement
a. Black widow- shiny black w/red hour glass on ventral surface of abdomen.
Myth: Daddy long legs are the most venomous spiders in the world but lack mouthparts to inject venom.
b. Venom gland & stinger in tail
c. Modified pedipalps- pincers for grasping food/defense
d. Courtship dance where male “lays” sperm case and female “sits” on case to pick up sperm
e. 20-40 young brooded by mother on her back for about 1 month
a. Many are ectoparasitic- feeding on blood or tissue
b. Some permanent (follicle mite)
c. Some temporary (chigger)
a. All ectoparasites.
b. Bodies expand as they feed.
c. Breeding occurs on host.
d. Female drops off & lays eggs.
e. Can carry disease.
a. Carry/cause disease
1. Rocky Mountain Spotted Fever- ticks
2. Lyme’s Disease- ticks