These are Bumblebee Gobies(Brachygobius xanthomelas), a freshwater goby from Malaysia. They are grumpy little fish with lots of personality. I am super happy to have this new addition to my yellow themed Aquarium!
I really have to thank Aquatic Arts for these amazing gobies, especially because these are the only truly freshwater bumblebee goby species.
My understanding is that no matter what the LFS tells you, you can’t reliably tell the species of Bumblebee Goby apart. Not all are freshwater either; however many species do live comfortably long term in hard freshwater, all Brachygobius live just as well in brackish.