Brachygobius

Though this species appears on ornamental trade lists quite often the name appears to be routinely misapplied to other species, particularly B. doriae. It can be diagnosed as follows: <30 lateral scales; two black body bands reaching ventral midline posterior to anal-fin; band above anal-fin als...

This species is among the more frequently-traded members of the genus, although confusion regarding its identification and natural distribution is commonplace and it's often misidentified as B. nunus or B. xanthozonus. It can be diagnosed as follows: <30 lateral scales; one black band on head, three on body; first black band on body overlapping first dorsal fin to the extent that almost all fin, except a narrow margin, is black, and beginning opposite centre of opercle...

It can be diagnosed as follows: <30 lateral scales; two black body bands reaching ventral midline posterior to anal-fin; band above anal-fin also reaching ventral midline no black band on head, though the first band may touch the posterior margin of the eye; band above anal-fin not reaching ventral midline; 6 branched anal-fin rays; 7-8 predorsal scales. Brachygobius currently contains 9 described species but is likely to prove more diverse should a review be carried out. Alt...

Apparently restricted to slow-moving or standing freshwater habitats such as marshes, temporal swamps and floodplains where aquatic vegetation and submerged grasses proliferate. One locality consisted of undisturbed marshland with lightly tannin-stained water and dense growth of Vallisneria spp.

Type locality is the 'river below Calcutta' which corresponds to the western side of the Ganges River delta south of Kolkata, West Bengal state, with reports as to its wider distribution varying significantly. It's sometimes said to be present throughout India plus both mainland and maritime southeast Asia, but is more likely restricted to India, Bangladesh, Sri Lanka, and possibly Myanmar.

B. sabanus is very similar to B. doriae and these two are easily confused. However in B. doriae most of the first-dorsal-fin and two-thirds of the pectoral-fin are black while in B. sabanus the last one or two rays of the first dorsal-fin are colourless and less than half of the pectoral-fin is black. In addition there are usually smaller dark 'saddles' betw...

Type locality is '55 miles north of Singapore, freshwater ditches, Mawai District, Johore, Malaysia', and this species has been recorded throughout much of Peninsular Malaysia and southern Thailand. Records from Borneo and Singapore appear to be in error although it may have been extirpated from the latter but as with most members of the genus a degree of confusion surrounds its identity (see 'Notes').

B. xanthozonus can be considered something of an enigma since its name has been widely misapplied in aquarium literature for decades, when in reality it's probably never been exported for the ornamental trade. The majority of fish seen labelled as such are either B. doriae or B. sabanus, themselves often misidentified.