Arthropoda
arthropods:
Overview 63
slides:
trilobite larvae w.m. (these are actually larvae of the horseshoe crab – trilobite larvae and horseshoe crab larvae are remarkably similar)
insect trachea R72
Dermacentor andersoni w.m. (tick) L65 Fig 10.5; L66 Fig 10.8; T341 Fig 14.11(e)
Cyclops w.m. R71
Ctenocephalides w.m. (flea) L74 Fig10.36; T234 Fig 12.40
Pediculus corporis (=humanus) w.m. (body louse) T234 Fig 12.42
Pediculus corporis (=humanus) – ova (eggs called nits, glued on threads of clothing)
Cimex lectularius w.m. (FYI) bed bug
Phthirus pubis w.m. (FYI) crab louse
external anatomy of:
horseshoe crab L64 Fig 10.2; T339 Fig 14.10(a & b) – simple eye, compound eyes, cephalothorax (prosoma), abdomen, chelicerae, pedipalps, telson
Questions for your lab notebook
Match the arthropod subclass with representative animals or characteristics:
| body divided into head, thorax, and abdomen; 3 pairs of walking legs; 1 pair of antennae, primarily terrestrial | a. Chelicerata |
| lack antennae and mandibles; 1st pair of walking legs are chelicarae used for feeding; 2nd pair are pedipalps; 4 pairs walking legs | b. Crustacea |
2 pairs of antennae; biramous appendages |
c. Myriapoda |
| crayfish, lobsters, crabs, shrimp | d. Hexapoda |
| insects | |
| millipedes, centipedes | |
| marine and aquatic; except one group (the isopods) have invaded the land. | |
| horseshoe crabs, spiders, scorpions, ticks, mites |
What is the composition of the arthropod exoskeleton? What are the advantages of an exoskeleton? What is a disadvantage?
What class of arthropods has the most species?
Problems associated with living and reproducing in terrestrial environments include locomotion, gas exchange, excretion, and development in desiccating environments. Explain how insects have overcome these problems?
Of the different ways insects move, which
is the most important from an evolutionary perspective?