Ray’s succeeded with Katherine (5)
I believe the answer is:
skate
'ray's' is the definition.
(skate is a kind of ray)
'succeeded with katherine' is the wordplay.
I cannot quite understand how this works, but
'succeeded' could be 's' (genealogical abbreviation) and 's' is present in the answer.
The remaining letters 'kate' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for skate that I've seen before include "Lasso" , "Food fish" , "Fish; ice shoe" , "Runner" , "Fish of ray family" .)