The most common and most likely answer to this crossword clue is the 4 plus 6 letter word PINE MARTEN
I've seen this crossword clue in The Daily Telegraph
P
I
N
E
M
A
R
T
E
N
More clues leading to the result PINE MARTEN
- Damage trap erected beneath tree to get furry critter
- Weasel’s relative staff and I put back in absurdly long hole?
- Animal in popular end of cattle market bought by writer
- Animal in minaret forced into cage
- Weaselly type, dodgy Pinner mate
- Furry creature, one engaged in permanent frisking
- Bad temper in an arboreal mammal
- Animal‘s popular tamer panicked, trapped by cage
Buddy explains!

The straight part
We know that "Animal" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case animal = pine marten.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.