Corydoras orcesi
Formally speaking, Corydoras orcesi is a synonym of Corydoras pastazensis. In the different photos you can see a difference in the markings of these species. Corydoras pastazensis has smaller dots instead of spots on the flank. The species do not occur together and the different markings do not rule out the possibility that orcesi turns out to be a separate species.
The name Corydoras consists of two parts: Cory means “helmet” and doras means “skin”. The name is a reference to the double row of bony plates under the skin on the flank of this genus. These bony plates act as a kind of armor, hence the common collective name for this group of fish: Armored Catfish. Due to the possession of the bony plates, they do not need any further protection, so they do not have scales. The species name orcesi was chosen in honor of Dr. Gustavo Orcés-Villagomez.
Description
Corydoras orcesi can reach a maximum length of about seven centimeters. The ground color is light brown with larger black spots. A vertical black band runs downwards from the first ray of the dorsal fin. A second band runs vertically over the eye.
The males are somewhat slimmer and smaller than the females. This is especially visible from above. The fins of males also become more pointed as they get older, while females are more rounded.
If you look closely at the nose of this species you will see that they have a kind of saddle nose. It falls inwards a bit, instead of being rounded a bit, as with many other species.
Biotope
Rio Tigre and Rio Conambo in Ecuador.
Diet
Using their barbels, Corydoras orcesi search the substrate for something edible. You can feed them with tubifex, red and black mosquito larvae, artemia, and daphnia. Sinking tablets and flake food are also eaten.
The aquarium
This peaceful schooling fish lives on the bottom. Despite their small size, they still need some space there. We recommend keeping them in a group of at least six, but preferably more. For a group of six, you need an aquarium with a minimum length of about 80 centimeters.
Use rounded (filter) sand on the bottom so that they do not damage their barbels when looking for food. Make sure there are some hiding places by using lots of plants and wood. Leave some sand open in the front and middle so that they can search for food and you can enjoy these active fish yourself.
The water may have a temperature of about 22 to 26 degrees Celsius with a pH of 6.0 to 7.5.
Suitable tankmates are peaceful Tetras that swim in the middle and upper layers of the aquarium. It can also be easily combined at the top of a group of hatchet fish. A combination with bottom-dwelling dwarf cichlids such as Apistogramma is not recommended. These cichlids form a territory that the group Corydoras orcesi does not care about. Especially if the Cichlids have a nest of young, this causes a lot of stress for the Cichlids. The Corydoras then simply bulldoze through the nest with eggs.
Breeding aquarium and conditioning
The cultivation of Corydoras orcesi is like most other Corydoras species. Prepare a breeding aquarium that is only set up with a layer of sand on the bottom. Give the parents some hiding places in the form of some Java moss. Make sure there is sufficient flow and aeration in the aquarium and direct the flow towards the glass. This will usually be the place where the eggs are laid.
Now add the parent stock in a ratio of 2 males to 1 female.
Food is an important part of conditioning the fish. Feed them meaty food such as black mosquito larvae, tubifex etc. Keep doing this until you see that the females are full of eggs.
The Spawn
The trigger for spawning, as with many other Corydoras species, is a large water change of about 50%. Use water that is considerably colder than the aquarium water. The water should be soft and slightly acidic with a pH of 6.5 – 7.0. Repeat this major water change twice a week until the eggs are laid.
In some cases, a 50% water change is not sufficient. In that case, increase the amount of fresh water to about 75% and increase the aeration and flow in the aquarium.
The dominant male chases a female. Eventually they take the T position characteristic of Corydoras. The Corydoras orcesi male grabs the female by her barbels with his pectoral fins. He pushes the female around hard. This is so rough that the female’s barbels can be damaged. After a maximum of about 10 seconds, she breaks away from the male. The female then releases an egg, which she catches with her pelvic fins. With the egg clamped between her fins, she looks for a suitable place to stick the egg. This can be on the glass but also in some Java moss.
The first few times the number of eggs is not very large, about 10 to 15 eggs. As the female becomes more experienced, this number increases to a maximum of about 30 eggs per time.
Raising the fry
Unfortunately, you cannot leave the eggs with the parents, because then they will be eaten. You can place the parents back in their community aquarium, but most breeders leave the parents in the breeding tank and move the eggs. You can usually carefully roll the eggs over the glass with a finger. The advantage of leaving the parents alone is that they will likely lay eggs again a week later. You should then continue to change with cooler water twice a week.
Place the eggs in an aquarium with the same water as the parents and again ensure sufficient flow and aeration.
Corydoras eggs mold quickly. Remove the moldy eggs to prevent them from infecting the other eggs. If the eggs continue to get moldy, you can add a few drops of methylene blue to prevent mold. Unfortunately, this drug is now only available with a prescription in the Netherlands, but in Belgium it can still be ordered freely.
The eggs hatch after 3 to 4 days. They then live on their egg yolk for a while. Only when they have eaten their egg yolk can you feed them very fine food such as microworms and liquifry. Once a bit bigger, around two weeks you can start giving finely crushed flake food and freshly hatched brine shrimp.
It is important for the young Corydoras orcesi that water is changed frequently and frequently, up to about 50% per day. Please note that there should not be large fluctuations in water values such as temperature and pH.
Transporting Corydoras
Many Corydoras species have a venomous self-defense mechanism to avoid being eaten by larger fish. In case of danger, they can spread and lock the spines in their dorsal and pectoral fins. As a result, they get stuck in the mouth or throat of the attacker, so that another fish will not want to swallow a Corydoras. Even when catching a Corydoras with a net, they regularly hang in the net with these spines. Be careful when loosening, if the spine gets into your skin it can partially break off and remain in the skin. These wounds are painful and often become inflamed.
In addition to the pointy spines, some Corydoras species can release a toxin into the water when stressed or in danger. When transported in too small a volume of water or too many Corydoras in the small space, this can lead to rapid death among the fish. It is therefore preferable to only transport the Corydoras with other Corydoras and not too much in one bag. Because little research has been done on this venom, it is not clear whether this venom is spread from the gills or from the spines. It is thought that at least the Corydoras adolfoi, Corydoras arcuatus, Corydoras melini, Corydoras metae, Corydoras panda, Corydoras robineae, Corydoras rabauti, Corydoras atropersonatus, Corydoras sterbai and Corydoras trilineatus have this poison, but it is advisable to pay attention to the other species as well.
Author
John de Lange
Copyright images
Hung-Jou Chen
AquariumGlaser.de
References
