LOGIN

RSS Facebook Twitter YouTube
GLOSSARY       

SEARCHGLOSSARY

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

PROFILESEARCH

Betta picta (VALENCIENNES, 1846)

Java Mouth-brooding Betta

Classification

Order: Perciformes Family: Osphronemidae

Distribution

Endemic to Java, Indonesia. No type specimens are known but Roberts (1993) gives type locality as ‘environs de Buitenzorg’, a former name for the modern city of Bogor in the west of the island, and the species appears endemic to western and central parts of the island.

Habitat

Usually associated with clear, flowing hill streams where it can be found in quiet marginal zones and still pools that typically contain a mixture of leaf litter and gravel/rocks. At some localities the water seems to be stained slightly brown, presumably with humic acids and other chemicals released by decaying organic material.

Maximum Standard Length

40 – 50 mm.

Aquarium SizeTop ↑

An  aquarium with base measurements of 60 ∗ 30 cm or equivalent is large enough for a pair or small group.

Maintenance

This species can be maintained in a well-planted aquarium, but most breeders of B. picta use bare-bottomed tanks. You can add a thin layer of sand or gravel if you prefer. Add a few driftwood roots and branches, placing these in such a way that a few shady spots are formed.

If you can’t find driftwood of the desired shape, common beech or oak is safe to use if thoroughly dried and stripped of bark. Clay plant pots or lengths of piping can also be included to provide further shelter.

The addition of dried leaf litter (beech or oak is probably best as the popular Ketapang almond leaves tend to leach a lot of tannins which may have an adverse effect on this clearwater species) could further emphasise the natural feel, as well as offering a little extra cover.

The tannins and other chemicals released by the decaying leaves are thought to be beneficial for the fish and the growth of microbe colonies will occur. These tiny creatures can provide a valuable secondary food source for fry. Leaves can be left in the tank to break down fully or removed and replaced every few weeks.

Like others in the genus this species seems to do best under fairly dim lighting. You could add aquatic plant species that can survive under such conditions, such as Microsorum pteropus, Taxiphyllum barbieri or perhaps some potted Cryptocorynes. A few patches of floating vegetation would be really useful to diffuse the light entering the tank too.

Also keep the tank well-covered and do not fill it to the top as like all Anabantoids it requires access to a layer of humid air above the water surface and members of this genus are typically excellent jumpers.

Water Conditions

Temperature: 71 – 75°F/22 – 24°C

pH: Not as fussy as some congeners. Provided conditions are on the acidic side of neutral no problems should arise.

Hardness: Use soft water 0 – 5°H.

Diet

In nature it probably eats small insects and other invertebrates, but captive fish will normally accept dried foods once they are recognised as such. Like all fish it does best when offered a varied diet. In this case regular meals of live or frozen foods such as Daphnia, Artemia or bloodworm should ensure the development of the best colours and condition.

Take care not to overfeed as Betta species seem particularly prone to obesity. Some experts have also warned of health problems developing when they’re fed excessive quantities of Artemia, especially in young fish.

Behaviour and CompatibilityTop ↑

Not a recommended choice for the standard community set-up for reasons already touched upon. It’s care requirements and disposition mean it is best kept alone or with very peaceful, small species.

When kept alongside bigger or more vigorous tankmates it can be outcompeted for food and may become shy and withdrawn. Potential options include dwarf Corydoras, Otocinclus, and small cyprinids such as Trigonostigma or Boraras. Also note that the presence of any other fish in the tank can be a distracting influence should a pair decide to spawn.

Provided the tank contains plenty of hiding places and broken lines of sight there’s no reason why a group of these cannot be maintained together. Although a little squabbling is inevitable (especially between males) it is generally quite a peaceful species.

Sexual Dimorphism

Males are the more colourful sex when mature, possessing a larger amount of iridescent scaling on the head and body and colourful patterning in the unpaired fins. The head profile in males is also noticeably stockier than in females, a physical adaptation to the mouthbrooding of eggs and fry.

Reproduction

By all accounts this species isn’t too difficult to breed if the fish are provided with the correct water conditions and diet. You’ll need to organise a separate tank for the purpose unless they are already being maintained alone, setting this up as suggested above.

The tank should have the tightest-fitting cover you can find (some breeders use clingfilm instead, to ensure no gaps) as the fry need access to a layer of warm, humid air. Without this the development of the labyrinth organ can be impaired.

A single pair or group of fish can be used, and feeding a varied diet containing plenty of live and frozen foods should bring them into spawning condition. It is the female that plays the more active role in both initiating courtship and defending the area against intruders.

Eggs and milt are released during a typical Anabantoid embrace in which the male wraps his body around that of the female. Several “practice” embraces may be observed before any eggs are released, in some cases several days before a genuine spawning event is seen.

Eggs are laid in small batches and are picked up in the mouth of the female before being spat out into the water for the male to catch. This process can take some time, sometimes with the pair even continuing to embrace before the female has got rid of all the eggs in her mouth. They are always collected again if the male misses them though.

Post-spawning the female continues to be the more dominant fish and some reports recommend removing her after a few days in case she wants to spawn again, disturbing the male before he has finished incubating. This normally takes 9 -12 days days at which point the male will begin to release fully-formed fry from his mouth.

Apparently the parents will not harm these and some breeders have reported them to develop at a faster rate when left with the parents. However any other fish present (including conspecifics) do pose a threat to the young so in this scenario it’s recommended to transfer fry or adults to a separate tank.

The fry are big enough to accept motile foods such as microworm and/or Artemia nauplii (see above notes on the feeding of Artemia to young Betta) immediately. Feed them small amounts of different foods 2 -3 times per day for the best rate of growth. Small (5 – 10% of tank volume) daily water changes can also be introduced to prevent organic wastes accumulating.

NotesTop ↑

Betta picta lends its name to the Betta picta complex of closely-related species, an assemblage which also includes B. falx, B. pallida, B. simplex and B. taeniata. These can be tricky to tell apart, as all can appear superficially similar at first glance.

An easy way to tell B. picta apart from B. simplex and B. taeniata is to look at the blue band on the distal (outer) edge of the caudal fin. Pale and relatively indistinct in B. picta, it is more well-defined and usually of greater intensity in the other two species. B. pallida is also easily-distinguished by its lanceolate (lance-shaped) caudal fin, as in all the other species in the group this fin is rounded.

It’s most similar in appearance to B. falx but in their 1995 review of the Anabantoids of Sumatra Tan and Ng noted the following: “Betta falx is closely related to B. picta from Java. It differs from B. picta in the following characters: lower dorsal fin ray count (mode 8 vs. 9); lower lateral scale count (mode 27 vs. 28); dorsal fin origin above 11-12th lateral scale (vs. 12-14th); anal fin origin below modal 6th lateral scale (vs. 7th); lower predorsal scale count (mode 19 vs. 20); slightly greater anal-fin base length (46.5-50.3% SL vs. 42.6-48.4); in life – males with distal margins of anal and caudal fins reddish (vs. bluish); iridescent greenish-blue opercle scales (vs. yellow-gold); preserved material – male with distinct dorsal transverse bars (vs. faint); male with distinct dark anal distal margin wide (vs. narrow); male without elongated median caudal fin rays (vs. presence); female with distinct caudal transverse bars (vs. very faint or absent); dorsal head view narrow (vs. broad); thick preorbital black stripe (vs. narrow); and the distance between posterior part of anal fin to lower part of caudal narrow (vs. wide).” In addition some experts state that the two can be distinguished by the presence of spots in the anal-fin of B. falx that are not present in B. picta.

The genus Betta is the most speciose within the family Osphronemidae with almost 70 recognised members and looks set to grow further with new ones continuing to be described on a regular basis since the turn of the century.

Member species have successfully adapted to inhabit a variety of ecological niches from stagnant ditches to flowing hill streams including some extreme environments such as highly acidic peat swamp forests.

The referral of members to a number of groups containing closely-related species is now generally accepted but largely based on morphological/behavioural characters. Molecular phylogenetic work is thus required and would undoubtedly prove useful in more precisely determining relationships between these fishes.

A full list of the species groups as currently recognised can be found here.

Like others in the suborder Anabantoidei this species possesses an accessory breathing organ known as the labyrinth. So-called due to its maze-like structure this organ allows the fish to breathe atmospheric air to a certain extent.

Comprising paired suprabranchial organs formed via expansion of the epibranchial (upper) section of the first gill arch and housed in a chamber above the gills, it contains many highly-vascularised, folded flaps of skin which function as a large respiratory surface. Its structure varies in complexity between species, tending to be better-developed in those inhabiting harsher environments.

References

  1. Tan, H.H. and P.K.L. Ng. - Raffles Bull. Zool. Supplement (13): 43-99. 2005
    The fighting fishes (Teleostei: Osphronemidae: Genus Betta) of Singapore, Malaysia and Brunei.

No Responses to “Betta picta – Java Mouth-brooding Betta”


Leave a Reply

You must be logged in to post a comment.