SCOTCAT.COM  

his Corydoras/Osteogaster species is usually the first one kept by aquarists and subsequently leads them into the fantastic world of catfishes. Many new exiting colour varieties are beginning to appear in the hobby mostly from Venezuela and Peru, these include the “Peru Green-Stripe”, the “Peru Gold-Stripe” and the “Peru Gold-Shoulder Red”, there is also a black variety, it may be in the future that these fish will be reclassified into a new species, only time will tell.

-

Osteogaster aenea

In the early days of the modern hobby this Cory along with Hoplisoma paleatum, the 'Peppered Cory' was the main diet of catfish enthusiasts as there was not much call for importing exotic species as keeping catfish was not as popular as it is today, and with the world opening up with faster trade routes and the growing popularity for catfish, and indeed other exotic species, we have today hobbyists themselves who go and collect these species and bring them back to their tanks.

This Corydoras/Osteogaster is abundant in the hobby mainly due to their breeding in fish farms in the Far East and I think that this has given us a poor representation of O. aenea in the aquatic shops today. You can still find good specimens but you will have to shop around and fish auctions can throw up a surprise or two. The albino variety is also very popular with first-time hobbyists. This is probably why the serious Cory enthusiast tends to overlook this species which has been with us for so long.

If you are starting off with this species, buy at least half a dozen, as with most Corys, they are happier in their own company. The comparatively low price of O. aenea (apart from the new varieties) would certainly not break the bank, and you could, of course, end up with at least a pair of these hardy Corys.

Breeding is comparatively easy with cool water changes that lower the temperature, triggering them off. Feed a good balanced diet making sure that they get their full quota of food if kept in a community tank. A good quality flake food provides all the essential vitamins they need with extra feedings of frozen bloodworm, white worm (sparingly) and tablet food. The new varieties mentioned earlier are not quite so easy to breed and need a little more work. In the two following pictures you can see male and female albino with the eggs laid high up on the glass front in the full flow of an internal filter. The second photo shows the fry against a one new pence (U.K.sterling).

Below is a gallery of a few of the new so-called aenea varieties, just click on the thumbnail to get a larger image.

	Normal bronze; Photo Credit: C.H.Bishop
	Albino; Photo Credit: Kathy Marshall
	Gold Form; Photo Credit: Adrian Payne
	Green Laser; (CW009) Photo Credit: Adrian Payne
	Black aenea - schultzei; Photo Credit: Sandy Milne

Make sure that you keep them in rounded gravel or preferably on sand as sharp gravel can erode the barbels, making them virtually useless for breeding, especially on the females. Even if you do keep your Cory's on rounded gravel or sand, do keep the substrate clean as a build up of bacteria there can also harm their delicate barbels.

As there is so many so-called varieties of O. aeneus, it would be better to keep the them apart in case of hybridisation.

Remarks: Placed in Lineage 7 alongside other members of the so called "aeneus group" with the designated type species: C. eques. A revision in the future would constitute the resurrection of the genus name Osteogaster Cope, 1871. As of the latest update Corydoras aeneus has now been placed in Lineage 7 and has the new genus name of Osteogaster and a change to the specific name to aenea (Dias et al 2024).

Bronze Cory

Corydoras schultzei, C. macrosteus, C.venezuelanus, C. microps, Hoplosoma aeneum, Corydoras aeneus

Corydoradinae

Brazil - Ecuador - Surinam - Venezuela - Colombia - Peru - Trinidad - Argentina, northern. Widely distributed in South America on the eastern side of the Andes, from Colombia and Trinidad to La Plata River basin. Type locality: Island of Trinidad, West Indies.

Male: 6.5cm, (2½ins) Female: 7.5cm. (3ins)

20-27°C (67-81°F)

Dorsal 1/7; Anal 1/6-7; 21-23 bony scutes in the upper lateral series, 19-21 in the lower.

Will do well in a community setup with smaller tankmates such as Rasboras and Tetra's. Do not house with aggressive species or large Cichlids.

Like to lay their eggs (300 or more) in the direct flow of a filter usually high up on the glass where the flow strikes. Eggs will hatch in 3 to 4 days and will use up their yolksac after 3 days. I did find that the O. aeneus 'albino' fry are a little more difficult to raise to adulthood, than some other Cory's, so keep the water changes up. (See image of spawning sequel with the eggs high on glass in the flow of internal filter and the fry in a small plastic holding tank.)

The fry after 3 days feed on infusoria then on to microworm, fry flake, then progress on to Brine Shrimp naupli. Adults can be fed the usual good quality flake food, frozen bloodworm, tablet foods, white and grindal worms.

Osteogaster: ostéon, bone; gast, belly, referring to coracoid bones of Osteogaster eques, which, unlike those of Gastrodermus elegans, enclose the ventral region.
aenea: Bronze.

Angelica C Dias, Luiz F C Tencatt, Fabio F Roxo, Gabriel de Souza da Costa Silva, Sérgio A Santos, Marcelo R Britto, Martin I Taylor, Claudio Oliveira, Phylogenomic analyses in the complex Neotropical subfamily Corydoradinae (Siluriformes: Callichthyidae) with a new classification based on morphological and molecular data, Zoological Journal of the Linnean Society, 2024;, zlae053.
Sterba's Freshwater fishes of the World Vol.1 1973.

Photo Credits

Top:       Haraldo Bishop
Bottom: Allan James @