Sign on a duo -- performing dinosaurs! (10)

I believe the answer is:

iguanodons

'dinosaurs' is the definition.
(iguanodon is a kind of dinosaur)

'sign on a duo performing' is the wordplay.
'performing' indicates an anagram.
'sign'+'on'+'a'+'duo'='signonaduo'
'signonaduo' with letters rearranged gives 'IGUANODONS'.

I've seen this clue in The Telegraph.

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