Lemur visible in thin drizzle (5)
I believe the answer is:
indri
'lemur' is the definition.
(indri is a kind of lemur)
'visible in thin drizzle' is the wordplay.
'visible in' indicates a hidden word.
'INDRI' is hidden in the letters of 'thin drizzle'.
(Other definitions for indri that I've seen before include "Short-tailed lemur of Madagascar" , "Big Madagascan lemur" , "large primate" , "native of Madagascar" , "Large Madagascan lemur" .)