Bumblebee goby

Geographic Origin and Biotope: Peat swamps and forest blackwater streams in Peninsular Malaysia and parts of Indonesia. Unlike its coastal cousins, it lives inland.

Taxonomy and Morphology: Freshwater Bumblebee Goby (Brachygobius xanthomelas). Smaller (max 1.5 - 2 cm / 0.6-0.8 inches) and more gracile than B. doriae. Complex taxonomy, often imported mixed with other species.

Social Behavior: Peaceful, static and shy. Must be kept in small groups (6-10 specimens). Spends hours perched on broad leaves or holed up in the dark substrate.

Coloration and Sexual Dimorphism: Typical yellow-black banded coloration ("xantho" = yellow, "melas" = black). The edges of the bands may be less defined compared to doriae. Sexual dimorphism evident only at reproductive age due to the swollen belly of the females.

Aquarium Setup: Nano aquarium of 40 cm (16 inches). Essential to set up a real Blackwater biotope: lots of peat, dry leaves on the bottom, intricate wood, subdued light and very dark water.

Diet and Feeding: Very slow sight hunter. Needs exclusively micro-live food (brine shrimp nauplii, vinegar eels) or microscopic frozen food (Moina, Cyclops).

Water Quality: Exception of the genus: strictly requires SOFT AND ACIDIC FRESH WATER (pH 6.0-7.0, low GH). Adding salt to this species would quickly lead to death by osmotic shock.

Compatibility and Tankmates: Given the millimeter size and the slowness in feeding, it must be paired only with timid nano-rasboras (e.g. Boraras brigittae) or kept in a species-only tank.

Aquarium Reproduction: Similar to other species of the genus. The male attracts the female into a tube or small cavity. In this species, the larvae do not require marine development phases, making freshwater reproduction slightly more accessible.

Risks and Diseases: Extreme vulnerability to confusion with B. doriae: if the shopkeeper does not know the exact species, they will be mistakenly placed in brackish tanks with fatal results in a few days.