User blog comment:PitchBlack696/Monster Hunter Portable 3rd/@comment-2190445-20101122191725/@comment-1011548-20101122212157

No monsters from Frontier after Season 1.5 (so not even Espinas) will come to any Monster Hunter PSP game, and no monster from Monster Hunter Portable 2nd G onwards will ever end up in Frontier - because Frontier is run by completely different people from those that run the rest of the series.

You can either take me at my word, or I can go to the effort of finding a link to back me up.