Small monkey (8)
I believe the answer is:
marmoset
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">small monkey</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for marmoset that I've seen before include "Small tropical American monkey" , "Monkey with claws" , "Take me to arms about bushy-tailed monkey of tropical America" , "Somme rat? (anag)" , "Small monkey - Rome's mat (anag)" .)