In sea urchins Pedicellaria

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1 in sea urchins

1.1 types
1.2 location
1.3 function





in sea urchins

enlarged pedicellariae of echinus


types

four main forms of pedicellariae found in sea urchins : tridactylous, ophicephalous, triphyllous , globiferous. there typically 3 valves make jaw of sea urchin pedicellaria. stalk composed of skeletal rod , flexible neck portion.


location

they attached long, inflexible stalk , may found anywhere on sea urchin s test.


function

in families, globigerous pedicellariae have evolved venomous structures, used protection or maybe hunting. particularly case in family toxopneustidae, species such tripneustes gratilla , toxopneustes pileolus being extremely venomous.




























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