A new build is being applied to the PTR and within it MMO-Champion discovered a new baby murloc! [source]
Murkablo - Right Click to summon and dismiss Murkablo.
This neat little creature appears to be a Diablo-themed murloc. Many are already speculating that it might be found in this year's Blizzcon goodie bag. However, it's entirely possible that it might be a Diablo 3 Collector's Edition companion, much like the Mini Thor was the pet that accompanied the Starcraft 2 Collector's Edition. We'll just have to wait and see!