adaptions of brachiopods Flashcards
strongly ribbed
strengthens shell against wave action
large pedicle opening
support a large pedicle for secure attachment to substrate
thick and heavy shell
provide extra stability on the substrate and prevent rolling in the current
zigzagged commissure
reduce amount and size of sediment moving into shells when valves are open
extension of the valves to form wings
provides a large surface area to prevent sinking into sediment
no pedicle opening
pedicle not needed for attachment in quiet water
valves flat with a large resting area
provides a large surface area to prevent sinking into sediment
weakly ribbed
no need to be robust in quiet conditions
margin turned upwards away from sediment
ensure that some part the shell remains out of sediment for feeding
median fold or sulcus
separates currents of water entering and leaving the animal. prevents mixing of fresh water and waste.
small brachial valve
acts as a lid to open for feeding and respiration
elongated ventral valve, cemented to substrate a base
for attachment in high energy environment
folded commissure
reduce amount and size of sediment moving into shells when the valves are open
spines from ventral valves
stabilise by extending these to the substrate, prevents overturning by a current
what type of brachiopod is best adapted for turbulent water?
Rhynchonelid
