ARTHROPODA (ADVANCED INVERTEBRATES)
Curtis:448- , Campbell’s 5th, pp 614-624, 6th: 662-675, 7th: 656-668, Sadava: 705-714, Campbell’s 9th: 684-692
4/5/82 rvsd 4/8/94, 4/7/95, 8 April 1996, 23 April 01, 9 April 02, 9 April 04, 11 April 05, 15Apr09, 12Apr10, 6Apr12
ARTHROPODA (Phylum): 684
protostome
Germ layers
GI tract:
Segmented
Respiration
Excretion
circulation
Nervous System
Exoskeleton (cuticle) chitin (poly NAG) plus lipoprotein. muscles
attach to exoskeleton move. Impermeable to water. Molting (ecdysis:
out of, put on) is necessary for growth
first "mouth" remains mouth, anus develops later
Bilateral, three layered
one way gut: tubular mouth to anus, coelum
some fusion seen in higher organisms, many appendages on segments
Appendages highly specialized: fangs, gills, jaws, antennae, claws, pincers etc
via tracheae (cuticle lined air ducts) and book lungs: leaf like plates, chitin lined chamber,
air drawn in via muscles.
Malpighian tubules collect H2 0 and N wastes, produce uric H+, empty into gut
Open heart in abdomen, pumps hemolymph to head, diffuses back through sinuses
cephalization. Cord ladder like, double set, with ganglia along ventral surface, more
dorsal at anterior, largest ganglia = brain. Brain seems to inhibit activity (control?) Male
mantis becomes sexually active after losing its head.
Subphyla, classes: (p 705) (changed from Chelicerata, Mandibulata...)
Sea Spider (“thick knees”)
Horseshoe Crab (“sword tail”)
Spiders
Crayfish (“shell bearing”)
Centipeds (“many feet”)
Insects (“into cut”) Hexopoda
Subphylum Chelicerata: (Chelos = claw) one or two body parts
(P 687)
six pairs of appendages (last four pairs =legs)
have fangs , but no antennae and mandibles
EX: Horseshoe crab, scorpions, ticks, spiders
ARACHNIDA:
first usually appendage fang-like, sharp, some poison
EX: spiders, mites, ticks, scorpions, daddy long legs.
Subphylum Mandibulata: have antennae and mandibles ( jaws)
CRUSTACEA: (691) mandibulates have appendages on abdomen, 2 pair of antennae
EX: crabs, crayfish, lobsters, barnacles, shrimp, pillbugs. etc.
MYRIAPODA: (712) [Uniramians:] single pair of antennae, unbranched appendages
EX: centipeds, millipeds [insects]
DIPLOPODA two pairs of legs per segment, herbivorous. Examples: millipedes
CHILOPODA “lip foot” because of poison “foot lip.” carnivore
One pair legs per segment: centipedes
INSECTA (HEXAPODA)
three divisions of body, six legs, one pair of antennae,
(P 688)
2 pairs wings [See separate sheet of notes on insects]