Amphibian got turned over crossing bank by river (4,4)
I believe the answer is:
tree frog
'amphibian' is the definition.
(tree frog is a kind of amphibian)
'turned over crossing bank by river' is the wordplay.
I cannot quite see how this works, but
'over' could be 're' and 're' is located in the answer.
'river' could be 'r' (abbreviation for river) and 'r' is found within the answer.
This explanation may well be incorrect...
'got' acts as a link.
Can you help me to learn more?
(Other definitions for tree frog that I've seen before include "Amphibian found in the branches?" , "High jumper" , "Arboreal amphibian" .)