A pony's transformed with lei - in this Pacific region? (9)
I believe the answer is:
polynesia
'this pacific region?' is the definition.
(I've seen this before)
'a pony's transformed with lei' is the wordplay.
'transformed with' indicates an anagram.
'a'+'ponys'='aponys'
'aponys' anagrammed with 'lei' makes 'POLYNESIA'.
'in' is the link.
(Other definitions for polynesia that I've seen before include "large group of islands" , "Extensive group of Pacific islands" , "Pacific region?" , "Islands including Hawaii, Tonga, Samoa, etc." , "Pacific islands incl. N Zealand, Samoa and Hawaii" .)