User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-4502434-20130922033739/@comment-17735225-20130922121628

Actually(Surprisingly) Basarios is in as high as 7th place in the japanese popularity poll (the 5th and 6th place are Akura and Espinas, respectively). So Gravios might be included because Basarios is in this game :P.

But I'm not sure about the sources so I might be wrong here.

http://www.pixiv.net/member_illust.php?mode=medium&illust_id=7333727 (if you have pixiv account, this actually has the artist commenting on it about how he based the order from the poll)

http://danbooru.donmai.us/data/2bf419a04e20c4ce16b4c71f0a6c75d6.jpg (For you who don't have pixiv account)

But Gravios sure brings back memories. In MH1/MH2 (PS2) times we used to solo melee a high rank Gravios in front of other 3 people just to show them that we can do it.