Ray's the chap getting the thanks (5)
I believe the answer is:
manta
'ray's' is the definition.
(manta is a kind of ray)
'chap getting the thanks' is the wordplay.
'chap' becomes 'man' (chap can mean a man).
'getting' says to put letters next to each other.
'the thanks' becomes 'ta' (UK informal version of 'thank you').
'man'+'ta'='MANTA'
'the' acts as a link.
(Other definitions for manta that I've seen before include "Devilfish" , "Giant ray" , "Kind of ray" , "Large ray" .)