Grunting beast rising up to capture small insect and a large mammal (5,5)
I believe the answer is:
giant panda
'large mammal' is the definition.
'giant panda' can be an answer for 'mammal' (giant panda is a kind of mammal). I also know that 'large' relates to this answer.
'grunting beast rising up to capture small insect and a' is the wordplay.
'grunting beast' becomes 'pig' (I can't justify this - if you can you should give a lot more credence to this answer).
'rising up' says the letters should be written backwards (in a down clue, letters go up).
'to capture' indicates putting letters inside.
'small insect' becomes 'ant' (I've seen this before).
'pig' reversed gives 'gip'.
'gip' enclosing 'ant' is 'giantp'.
'giantp'+'and'+'a'='GIANT PANDA'
Can you help me to learn more?
(Other definitions for giant panda that I've seen before include "Something native to China" , "Large black and white mammal" , "endangered species" , "Creature" , "furry animal" .)