Where do you find #140 or #141?

Hunter Island Where's that Monster
#1

Preferably 140

#2

He spawns in the cave northeast of earun, you can check Lachzeers guide, which is pinned in the where’s that monster forum for a screenshot of the cave location. 

Link for convenience

http://www.hunterislandforum.com/index.php/topic/322-lachzeers-location-guide-to-catching-rare-arkadions/