ch 22: crustacea Flashcards
6 feat of crustaceans
- great diversity of body plan
- mostly aquatic
- head w/ up to 5 pairs of appendages incl mandibles and 2 pairs of antennae
- compound eyes
- biramous appendages
- nauplis larvae w/ 3 pairs of appendages and 1 medial eye
class malacostraca (5)
- crabs
- lobsters
- shrimp
- isopods
- amphipods
how many pairs of antennae do crustaceans have?
2
malacostraca morphological diversity
some taxa have many segments and many pairs of appendages
malacostraca features (2)
- head and thorax usually fused and covered by a carapace
- many spp have chromatophores
order decapoda (3)
- lobsters
- shrimps
- crabs
what other order is also called decapoda
squids, cuttlefishes (mollusca, cephalopoda)
order amphipoda
sand fleas
order isopoda
wood bugs
decapoda characteristics (2)
- cuticle hardened by calcification
- carapace fused w/ dorsum but not w/ sides
abdominal appendages in decapods (2)
- 5 pairs of swimmerets
- 1 pair of uropods
decapod chelae (3)
- used for defense
- tearing/crushing prey
- asymm
how many walking legs do decapods have?
5, posterior
decapod other walking leg functs (3)
- grasping/passing food
- digging
- carrying sensory bristles
lobster life cycle (3)
- no larval form
- direct development
- parental care
7 egs of crabs
- pea crabs
- mole crab
- hermit crabs (elongated abdomen)
- decorator crab
- kelp crabs
- dungeness crab
- temple crab
crab abdomen
shortened and tucked up under the boxier cephalothorax
crab life cycle (3)
- must mate right after F crab molts
- F carries eggs under body
- larval forms = zoea + megalops
4 features of amphipoda
- laterally compressed
- often curved like a C
- scavengers
- good jumpers
eg of amphipod pest
whale lice
order isopoda feats (4)
- dorsoventrally flattened
- mostly marine, some terrestrial
- herbivores/detritus eaters
- some are parasites
class branchiopoda
brine shrimp
class branchiura
fish lice
class cirrepedia
barnacles
mantis shrimp predation feats (2)
- compound eyes
- claws create a shockwave so strong it can break glass
branchiopoda feats (4)
- many swim upside down
- mostly in freshw
- filter feeders
- some are adapted to live in temp pools
ostracoda feats (5)
- tiny and abundant
- clam-like bivalved carapace
- most of body is head
- may bioluminesce
- tons of fossil spp, used to date rocks
copepoda feats (7)
- may be most numerous animal (copious!)
- primary consumers
- long 1sts antennae
- commonly have single, median eye
- abdomen w/out appendages
- nauplius larvae
- many are parasites
branchiura feats (4)
- dosroventrally flattened
- attach via suckers/hooks
- feed on blood
- salmon farm sitch
cirrepedia feats (5)
- sessile adults surrounded by calcareous plates
- adult has no antennae or abdomen
- suspension feeding using modified legs called cerae
- camoflague users
- still molt after settling
barnacle sex (2)
- hermaphrodites
- int fert of neighbours via long penis
what type of larvae do barnacles have
nauplius
cyprid, the last larval stage in barnacles do (4)
- does not feed
- selects site for adult stage
- seeks right conditions w/ food, conspecifics etc
- attaches via cement glands on antennae
barnacle meta (2)
- metamorphosis turnes swimming appendages into cirri
- tissue of carapace becomes mantle and secretes the calcareous plates
how are cirrepedia’s cirri extended
hemolymph
