I have the 2017 Del Rey Books mass market edition of *The Hitchhiker's Guide to the Galaxy*. Here is the front cover:

[![The cover of the 2017 edition][1]][1]

It features a circular green alien with two arms sticking its tongue out. Looking at other covers, the [first American edition also has this character][2]:

[![The first American edition's cover][3]][3]

**Who is this supposed to be? I have no clue.**


  [1]: https://i.sstatic.net/2Qr9k.jpg
  [2]: http://www.isfdb.org/cgi-bin/pl.cgi?315239
  [3]: https://i.sstatic.net/zTh02m.jpg