Lecture notes Biodiversity: Exploiters and Exploited Barnacles and Biofouling(BI2EEE4)

11.11.19


L7 – Barnacles and Biofouling

Definitions

Sessile (fixed and immobile), instars (moulting stages), antennules (small first pair of antennae),
biramous limb (limb that branches into two from one), carapace (hard shell of a
crustacean/tortoise), bivalve carapace (2 shell pieces bound by a muscular hinge), quorum sensing
(gene expression reg by fluctuations in cell-pop density)

 Barnacles
o Sessile & speciose (less so than insects)
o 60% live on rocks and 33% parasitic
o Subphylum = Crustacea
o Class = Cirripedia (900 species)
o Grow on structures (biofouling)
o Limpet camouflage (snails with wide cone-like shells)
 Staled barnacles
o Lepas sps
o Found on sailing ships bc cannot handle higher speeds
 Life cycle
o Pelagic stage
 Nauplius stage
 One eye (swims w/antennae)
 Brings food towards mouth (mandible)
 Antennules
 6 instars (1mm after 6th moult)
 Biramous limb
 Carapace (keratinous)
 Cyprid stage
 Doesn’t feed
 Binds to object
o Initially by sticking pair of antennules to surface
o Releases oxidative fluid – clean surface
o Then sticks by glue ducts/cement glands (resistant to
chemical breakdown)
 Used in dentistry to repair BVs/nerves
o Factors
 Water currents, surface texture, current and
chemical composition
 Bivalve carapace
 6 pairs of thoracic limbs
 3-4 weeks to settle or cannot
metamorphose
o Metamorphasis
 Flexation occurs
 Primordial plate appears
o Adult barnacle
 Loves 2-6 years