Betta ibanorum a rare anabantoid
Stefan van der Voort looks at Betta ibanorum, a rare anabantoid which has recently been imported into the UK for the first time.
Scientific name: Betta ibanorum Tan and Ng, 2004
Origin: Sarawak, Borneo.
Size: At least 13-14cm TL.
Water: This is where it gets a little tricky. There are numerous populations thriving in Sarawak of which most live in soft and acidic water (pH around 4, GH around 0 to 2) and some in clear water with a pH of 6 (GH unknown). The water temperatures can vary between 26 and 28 degrees Celsius.
Aquarium: Betta ibanorum needs a large tank; preferably 80 cm for a group of five, perhaps 60 cm for a pair. They need plentiful hiding places to seek refugee if needed. Plants, stones and wood all form reliable candidates, and what sort of plants depends on the pH and GH levels. Also add a substrate (gravel, beech/oak leaf litter) because it makes them feel more secure. Of utmost importance are regular (weekly) water changes with either fresh or prepared water, depending on the fish’ origins. This fighting fish is not suitable for a community tank but requires a species tank. This way they will feel better and will show their best side to the observer.
Diet: This Betta is easy to satisfy as they will readily take any frozen and live foods; Artemia, glass worm, bloodworm, mosquito larvae, krill, Mysis, Daphnia, insects, earthworms and dry foods such as granules. Do maintain an irregular pattern over the course of seven days during which they won’t get food for one or two days (not two in a row). This will keep them hungry (this is important as Betta are prone to obesity so fairly weigh the amounts given) and active as they will ‘go out’ and look for food themselves.
Sexual dimorphism: Males have more elongate fins; a larger overall appearance; broader head vs. sharper/pointed in females; more iridescence on the flanks.
Breeding: While writing this they haven’t been bred, yet. Though from its close relationship with certain other species and Betta ibanorum its build its clear that it is a paternal mouth brooder that will spawn more or less the same way as those closely related species.
During the typical labyrinth fish embrace (see earlier Interesting Imports) eggs and sperm are released after which the female collects the fertilized eggs. It’s not sure yet, though likely that also B. ibanorum will show a ballgame during which the female spits eggs to her spouse that needs to catch them in time, before the female recollects them for the game to start over again.
After a few hours their spawning is over and the male will retreat to a quiet place in the tank, with perhaps the female guarding him for ca three days. Do continue feeding the male during this time as he’ll be capable of taken very small amounts, which are, of course, always better than nothing.
How long he will brood the eggs in mouth depends largely on the water temperature, but with an average of 25 to 26 degrees Celsius it should take about seventeen days before he releases the fry. If the tank is densely planted the young ones can be left in with the parents for the strongest will survive, however for a larger number of young to grow up one should either remove the parents or the fry.
Immediately after they have been released they are already a few millimeters long and can be fed with freshly hatched Artemia, micro-worms or other, similar small foods. Combine good feeding multiple times a day with regular water changes and they will grow steady and fast, resembling their parents in a matter of weeks.
Notes: Specimens coming from acidic and soft water do not do well in tap water and for specimens coming from clear water it’s vice versa. So knowing where your fish exactly came from is very important.
Betta ibanorum are not really aggressive fish, except for the usual quarrel now and then. This is likely to change when they are spawning, though, so during that period a bit of supervision and caution is advised.
Adult colouration: Not the most colourful of fighting fish. The body has a soft brown ground colour with ice bluish iridescent scales (which may show different colours depending on how the light hits them). The operculum has some black markings and a black stripe starts in front of the eye, runs through it and ends at the lips, which are for the better part a dusky blackish. They eye itself has a yellow rim starting around 10:00 and ending at 17:00 (I here used the clock convention); the rest of rim is dusky to orange with a black iris. The dorsal, anal and caudal fins are pretty much hyaline except for a very smooth reddish-brown glow. Between the fin rays is a black ladder pattern (absent in the anal fin). Only the anal fin has an outer margin, which is black. The pelvic fins are also hyaline except for the large, white filaments.
Availability: Extremely rare. First UK import. Not available to the public yet.[TABS_R id=2079]
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