In sea stars Pedicellaria

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1 in sea stars

1.1 types
1.2 location
1.3 function





in sea stars

aboral surface of asterias forbesi sea star showing ring of pedicellariae surrounding spine.


types

there 2 major types of pedicellaria in sea stars: straight , crossed. straight pedicellaria typically larger , located on body surface, whereas crossed pedicellaria smaller , found more commonly on stalks, raised above body surface or in clumps circling spines. crossed type connected test elastic ligament.


location

sea star pedicellariae may located on test s surface or mounted on flexible stalks. depending on species, pedicellariae may surrounding spines, on surface of animal s body, in pits on abactinal, marginal, or actinal surface, and/or within adambulacral plate adjacent tube foot furrow. forcipulate sea star called because each pedicellaria typically composed of 3 forceps-like valves. other asteroids can have pedicellariae composed of 2 components.


function

pedicellariae in taxa, such deep-sea brisingida, , antarctic labidiaster known function in food capture.








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