Introduction to Cynolebias constanciae
Cynolebias constanciae is also known as Simpsonichthys constanciae. Its common name is Feather-fin pearl fish, since it has elongated fins with long rays, and is decorated with pearl-like markings. The body is light brown with big brown dots and a sprinkle of whitish pearl-like spots. The first specimens known to science were stumbled upon in a farm pond in South-Eastern Brazil and it took many years before anyone managed to find them anywhere else. They are currently listed as “Vulnerable” in the IUCN Red List of Threatened Species and you should therefore only purchase captive bred specimens, never wild caught ones.
Cynolebias constanciae grow up to 5 cm long in the wild and can be kept with other small, peaceful fish in a community aquarium. Unlike many other Cynolebias species, they males are not violent to each other. When well cared for, Cynolebias constanciae can live for nearly two years.
The aquarium should be well decorated with plenty of plants, rocks and driftwood. Keep the water temperature in the 22 – 25°C range. The pH-values should be around natural (pH 7) and the water hardiness under dH 10. Feed your Cynolebias constanciae a combination of meaty live food and high-quality flake food.
Spawning Cynolebias constanciae
Cynolebias constanciae is an egg laying, bottom spawning fish that has been successfully bred in captivity many times. Giving Cynolebias fish a lot of meaty food is a good idea if you want them to spawn. Some breeders have reported how using 3 parts tap water and 1 part R.O. water seems to promote spawning, but this does not seem to be mandatory.
If you want to breed Cynolebias constanciae, you must provide them with a suitable spawning site. This can for instance be a plastic box with a tight-fitting lid. Fill the box with wet, sterilized peat moss, and cut a hole in the lid, large enough for the fish to swim through. Place the spawning box at the bottom of the aquarium and wait for the fish to find it. If the box floats, put some pebbles or marbles inside it to weigh it down.
During spawning, the male Cynolebias constanciae will try to push the female into the spawning box. Sometimes, he has to work really hard to get her interested, and this behavior can go on for days or even weeks.
Mimicking a dry season
Cynolebias constanciae live in areas subjected to severe dry seasons. The eggs will therefore stay unhatched down at the bottom until the onset of the next rainy season. When breeding Cynolebias constanciae in captivity, you must therefore mimic a dry season with a following rainy season.
Start the “dry season” by removing the spawning box from the aquarium. Place the peat moss in a fine net and use the net to press out as much water as possible. Wrap the peat moss in newspaper or in a similar high-absorbent material and leave it to rest over night. This way, even more water will be extracted from the peat moss.
Place the peat moss in a plastic back (not a freezer bag) and tie it. Ideally put a sticker on the bag that says Cynolebias constanciae + date. It is surprisingly easy to forget about the content of an unmarked bag after a few months, especially if you keep several killifish species. Put the bag in dark place where the temperature is stable (room temperature).
Mimicking the onset of the rainy season
Cynolebias constanciae eggs normally needs four months of rest before they are ready to hatch, but some breeders have managed to make them hatch after no more than 12 weeks.
Place the peat moss in a container and cover it with plenty of water. The water should be colder than room temperature, since rain normally makes the temperature in drop in dry parts of Brazil. Add an airstone to the container and wait for the hatching to start. Some people throw in some daphnia culture in advance provide the newly hatched fry with suitable food.
If only a small fraction of the eggs hatch, you can squeeze out the water from the peat moss and leave it to rest in the plastic bag for a few more weeks before trying again.
Raising Cynolebias constanciae fry
You can feed the fry daphnia and newly hatched brine shrimp. When provided with a nutritious diet, Cynolebias constanciae fry will grow really fast. In the wild, they must reach sexual maturity and reproduce before the rainy season is over.
Didn't find the info you were looking for? Register for free and ask your question in our Aquarium forum !
Our knowledgeable staff usually responds to any question within 24 hours
Aphyosemion - Information about Aphyosemion
Breeding Clown Killies. Epiplatys annulatus - Information about how to keep and breed clown killies.
Breeding Fundulopanchax gardneri Jos Plateau - A detailed guide on how to keep and breed this species.
Breeding Rivulus hartii - the Giant Rivulus - This killifish proved easy to breed and raise.
Breeding the Blue Gularis, Aphyosemion sjoestedti - A guide to keeping and breeding the blue gularis..
Cynolebias - Information about Cynolebias killi fish.
Epiplatys - Information about Epiplatys killi fish.
How to Make a Spawning Mop - Detailed instructions on how to make a killie spawning mop.
Killiefish - Information about Killiefish
Killies - The Plant Spawners - The permanent and the mop methods of spawning. Incubation methods raising the fry.
Killie Mops - How to make and use these devices where killifish and other plant spawners can lay their adhesive eggs.
Nothobranchius - Information about Nothobranchius killi fish.
Shipping Killifish and Eggs. - A detailed article. Conditioning the fish. The water, bagging, containers. Carriers, receiving.
South American Killies - Cynolebias: True annual killifish that require slightly different treatment than Nothobranchius..
Triggers - Triggers for killifish to breed and what you can do to convince those in your tanks that they should hatch.
Understanding Killifish Names - An explaination.