[3] Males are generally slimmer than females and often have more vivid colours, typically orange rather than yellow.

[2] When spawning, the colours of the males become deeper, the orange bands becoming red in the case of Brachygobius doriae.

[2] This genus is informally divided by taxonomists into the dwarf Brachygobius nunus-species group (e.g., B. nunus, B. aggregatus, and B. mekongensis) and the bigger Brachygobius doriae-species group (e.g., B. doriae, B. sabanus, and B.

[2] There are currently nine recognized species in this genus:[4] Bumblebee gobies are found across Southern and Southeast Asia primarily in freshwater habitats but also in slightly brackish waters.

[2][3] Although many aquarium books use the name Brachygobius xanthozona, this species is very rare in the wild and is not commercially traded.