Classes Flashcards
Merostomata
-2 body regions
-cephalothorax and abdomen
-covered by exoskeleton
-joint appendages
-pincer-like chelicerate mouthparts
-heavy gnathobases spine
-book gills, increase surface area over which animal can absorb oxygen from the water
-horseshoe crab
Arachnida
-Chelicerate mouthparts
-pedipalps near mouth
-4 pairs of walking legs
-2 body regions, cephalothorax and abdomen
-no antennae
Chilopoda
-head and many segmented body
-2 antennae (1 pair)
-Mandibles, jaw like mouth parts
-poison fangs are first pair behind head
-1 pair of legs
-centipedes
Diplopoda
-head, many segmented body
-2 antennae (1 pair)
-2 pairs of walking legs (4) per segment
-produce bad smelling chemicals
-mandibles
-herbivore
-millipedes
Crustacea
-mandibles
-cephathorax and abdomen
-various number of appendages
-appendage on abdominal segment
-2 branched (biramous) appendages
-2 pairs on antennae (4) on head
Hexapoda
-head, thorax, abdomen
-3 pairs of walking legs on thorax
-segmented body
-no appendages
-2 antennae (1 pair)
-mandibles
-can have wings
What are and who have tracheal systems?
tubes exposed by spiracles for gas exchange
centipedes, millipedes, insects
Chitons (polyplacophera)
diverged early in Mollusk evolution. Fossil evidence indicates that they are closest to the ancestral mollusk body plan.
Gastropods
start with similar body plans as chitons, but their bodies go through torsion during development.
Nudibranchs (sea slugs)
a shell-less gastropod Many nudibranchs taste bad or are toxic and exhibit warning coloration. Some eat Cnidarians and store the cnidocytes in their skin.
Bivalves
have a two-part mantle that makes two hinged shells out of calcium carbonate. Most are filter feeders and are sessile. Bivalves do not have a radula. The foot is used for burrowing into sediments
Cephalopods
(octopuses, squid and cuttlefish) have a foot that is modified to form arms, tentacles and a siphon. Most cephalopods have either no shell or a very reduced shell.
