Brachygobius doriae (GÜNTHER, 1868)

Bumblebee Goby

SynonymsTop ↑

Gobius doriae Günther, 1868; Hypogymnogobius doriae (Günther, 1868)

Classification

Order: Perciformes Family: Gobiidae

Distribution

Described from the Malaysian state of Sarawak on the island of Borneo, and appears endemic to western parts of the island plus the Natuna Islands archipelago which lies off Borneo’s western coast but forms part of Riau Islands province, Indonesia.

On Borneo itself records exist from various localities in Sarawak and Brunei Darussalam, with the Kapuas river system, Kalimantan Barat (West Kalimantan) province, Indonesia, appearing to mark the limit of its eastward range.

Records from Singapore are apparently erroneous.

Habitat

Inhabits both fresh and brackish water, and generally restricted to lowland, coastal environments including mangrove swamps, estuaries, and tidal streams. Substrates thus tend to be composed of mud, sand and silt with overlying organic material such as leaf litter, mangrove roots, and submerged driftwood.

Some populations inhabit ancient peat swamp habitats with highly-stained, tea-coloured water, very low acidity, minimal conductivity, and negligible hardness.

Maximum Standard Length

25 – 35 mm.

Aquarium SizeTop ↑

Base dimensions of 45 ∗ 30 cm or equivalent should be the minimum considered.

Maintenance

Provide plenty of hiding places and cover, the idea being to create broken lines of sight to allow weaker individuals to escape continual attention from dominant fish.

Crushed coral or coral sand can be mixed into the substrate to act as a buffer if necessary, or marine salt added at a dose of around 2 grams per litre.

Filtration should not be strong with an air-powered sponge-type unit ideal.

Water Conditions

Temperature: 22 – 28 °C

pH: 7.0 – 8.5

Hardness: 143 – 357 ppm

Diet

Small live foods such as Artemia, Daphnia, etc., should be considered essential although some specimens will learn to accept  frozen alternatives. Dried products are normally ignored.

Behaviour and CompatibilityTop ↑

Does not make an ideal community fish and best kept in a species-specific set-up.

Although males in particular are territorial towards one another a group of 6 or more should be the minimum purchase since when such numbers are present aggression is spread between individuals plus the fish are bolder and exhibit more natural behaviour.

Sexual Dimorphism

Sexually mature females often appear rounder-bodied than males, particularly when gravid.

When in spawning condition males take on an overall reddish tinge with the dark bars on the body becoming paler, while the first yellow bar in females becomes brighter.

Reproduction

This species spawns in small caves with small flower pots, ceramic tubes, shells, or plastic camera film canisters all suitable (the latter may need to be weighed down somehow).

An individual male will select a site and display to female in the vicinity until he finds a receptive partner. Around 100-200 eggs are deposited in the cave after which the female departs, leaving the male to guard and tend the clutch.

Once a male is guarding eggs you may wish to remove any other fish present, or if possible the cave with male and eggs inside, to a different tank containing identical water in order to avoid fry predation. The incubation period is 7-9 days.

Once free swimming the fry require microscopic foods such as Paramecium or Brachionus until large enough to accept Artemia nauplii and suchlike. They are pelagic for the first few weeks of life, eventually settling on the substrate.

NotesTop ↑

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.

According to current knowledge it can be diagnosed as follows: <30 lateral scales; one black band on head, three on body; first black band on body beginning opposite centre of opercle and overlapping first dorsal-fin to the extent that almost all of the fin, except a narrow margin, is black; second black band reaching ventral midline posterior to anal-fin;  black pigment present on all rays of second dorsal-fin; opercular scales present; basal two thirds of ventral-fin black; basal two thirds of pectoral-fin black.

In some specimens there is an additional black marking between the first and second body bands, and in most cases the black bands are wider than the yellow interspaces between.

B. sabanus is very similar to B. doriae and these two are more-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’ between the dark body bands in B. sabanus which tend to be lacking in B. doriae, and there is a significant difference in maximum size between the two with B. doriae much the larger.

That said, intermediate forms displaying a mix of the above characters are common so they’re perhaps best considered nominal taxa for the time being since several species might be involved. Therefore, although we’ve assigned images to profiles based on how well they match the key of Inger (1958) their identification can only be thought of as tentative pending publication of a forthcoming review.

B. nunus is native to India, Sri Lanka, and Bangladesh and possesses 4 relatively thin dark bars on the body rather than the three wide bars seen in B. doriae and B. sabanus.

B. xanthozonus has 50+ lateral scales, a feature setting it apart from all other genus members and giving it an overall elongated appearance. It’s previously been placed in its own genus, Hypogymnogobius, is possibly endemic to Java, and not currently in the aquarium hobby.

Brachygobius currently contains 9 described species, and although all are referred to collectively as ‘bumblebee’ gobies only B. doriae and B. sabanus are commonly-available  in the ornamental trade. Both are sometimes referred to as ‘golden-banded goby’.

The grouping is often included in the subfamily Gobionellinae alongside genera such as Chlamydogobius, Mugilogobius, Pseudogobiopsis, Rhinogobius, Schismatogobius, and Stigmatogobius.

It’s considered most closely-related to the genus Pandaka with the two sharing numerous characters but differing in the morphology of the head lateral line system and number of epurals present.

References

1. Günther, A., 1868 - Annals and Magazine of Natural History (Series 4) v. 1 (no. 4) (art. 34): 264-266: 264-266
   Description of two new gobioid fishes from Sarawak.
2. Inger, R. F., 1958 - Fieldiana Zoology 39(14): 107-117
   Notes on the fishes of the genus Brachygobius.
3. Larson, H. K., Z. Jaafar, and K. K. P. Lim, 2008 - The Raffles Bulletin of Zoology 56(1): 135-155
   An annotated checklist of the gobioid fishes of Singapore.
4. Miller, P. J., 1989 - Cybium 13(4): 375-383
   The classification of bumble-bee gobies (Brachygobius and associated genera) (Teleostei: Gobiidae).
5. Roberts, T. R., 1989 - Memoirs of the California Academy of Sciences No. 14: i-xii + 1-210
   The freshwater fishes of western Borneo (Kalimantan Barat, Indonesia).
6. Tan, H. H. and K. K. P. Lim, 2004 - The Raffles Bulletin of Zoology Supplement 11: 107-115
   Inland fishes from the Anambas and Natuna Islands, South China Sea, with description of a new species of Betta (Teleostei: Osphronemidae).