Brachygobius
Brachygobius is a small genus of gobies. They are popular aquarium fish where a number of species are sold as bumblebee gobies because their colours are similar to those of bumblebees.
Morphology
Bumblebee gobies range in size from 1.5 cm to 4 cm. They are generally coloured black with pale yellow to orange bands. Males are generally slimmer than females and often have more vivid colours, typically orange rather than yellow. Females may also have smaller and rounder heads. When spawning, the colours of the males become deeper, the orange bands becoming red in the case of Brachygobius doriae.
Taxonomy
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. xanthomelas).
Species
There are currently nine recognized species in this genus:
Brachygobius aggregatus Herre, 1940 (Schooling bumblebee goby)
Brachygobius doriae (Günther, 1868)