One may be of interest to a lepidopterist operating abroad (6-3)
I believe the answer is:
orange-tip
'one may be of interest to a lepidopterist' is the definition.
(orange-tip is a type of butterfly)
'operating abroad' is the wordplay.
'abroad' indicates anagramming the letters.
'operating' is an anagram of 'ORANGE-TIP'.
(Other definitions for orange-tip that I've seen before include "Butterfly variety" , "British butterfly" , "Common butterfly" .)