With Cory’s breeding style, will they interbreed, with different varieties in the same tank???

[Magnum Man]

they are Oreochromis... um... I think

 

[GaryE]

I'll try with my favourite fish, Aphyosemion killies. We caught a cool thing called Aphyosemion joergenscheeli in Gabon. DNA studies suggest it is really ancient, and it's often seen as 'basal', as the start of the branch of life we call Aphyosemion. We also caught Aphyosemion primiginium, another ancient fish. That tells me we must have been in the region where Aphyosemions as a Genus first evolved.
The terrain was rugged, and most likely their streams never connect with the streams other Aphyos are in. They've been isolated since before humans were around. We got to run on quicksand to find primiginium.
Somewhere along the line, other branches appeared off the main stem or stems. Each one became genetically different, and became a species over time. Most of those branches produced other new branches, based on mutations and natural selection. The Genus of related fish suddenly (like over tens of thousands of years, maybe longer) had lots of member species.
I have bred an ancient species, Aphyosemion zygaima, since 1992. It has close relatives, according to DNA research, but it only has been found in one stream in a gorge that empties into an industrial farm. Between 1989 and 2021, various attempts to find it again failed. It was only some guys who decided to go into the very difficult ravine who discovered it hadn't been made extinct by the farm.
DNA says it's related to A. ogoense, ottogartneri, pyrophore and others. They share a common ancestor and might be able to hybridize, depending on how old they are as species. There are also related fish with no names, found recently and not studied. They're Aphyosemion "sp", until someone studies them.

So, practically. I keep my ottogartneri in different tanks from my zygaima. Each has its own distinct beauty, so why stick them in a species blender?

 

[Magnum Man]

as long as you brought up the blender... so, hormonal breeding or Test Tube breeding... what could be bred, & make a viable offspring ( springing back to the electric blue acara thread, where once it was made, would produce offspring, that look the same??? assuming the Genus has to be the same at least...

 

[GaryE]

I don't know those methods well, but I think they make a lot of tries for limited success. They can insert genes, like the jellyfish genes in glofish. And sperm and eggs can be combined like in parrot Cichlids, where the 'founder' species would kill each other. That seems more like artificial insemination.
The results are not considered species, but no name products.

Tilapia is a good example. Early on, they had one Genus name because they were "who cared" fish. Then they became economically important, and money appeared to study them. It became clear they weren't one Genus. Sarathrodon were tough and fast growing, so they became the fish of choice. Tilapia mariae became Pelmotolapia, which grew very large and was a contender, but Sarathrodon won out because of speed of growth. I think farmers have crossed Sarathrodon species looking for a magic bullet.

There are even some ex-Tilapia that are great aquarium fish. I used to have a little bright red fish that topped out as a dwarf Cichlid, on the larger end of the bunch. It was a Coptodon, a genus with big fish as well.

We saw enormous Coptodon in markets and barbecue restaurants in Gabon. Big Coptodon, Sarothrodon, and some very pretty, honking huge fish. When you travel with two Ichthyologists, you stop every time you see fishermen carrying their catch home. We saw and smelled some fish that would all have been called Tilapia 25 years ago.

 

[Essjay]

I have just been over to Planet Catfish. They are now calling the fish which used to all be Corydoras by their new names such as Oleogaster aenea, which used to be Corydoras aenus, the bronze cory; Hoplisoma habrosum, which used to be Corydoras habsosus, the salt & pepper cory; Gastrodermus pygmaeus which used to be Corydoras pygmaeus, the pygmy cory.

Because they are now in different genuses we now know there's no way bronze cories, salt & pepper cories and pygmy cories can interbreed.



I suggest heading over to Planet Catfish and entering the common names of your cories into their search engine to see what they are now called - though bear in mind that albino cories can be albino bronze cories, albino peppered cories and I think there's even an albino sterbai cory. You need to know which to see what new genus they are in to know if interbreeding is even a vague possibility.

 

[TwoTankAmin]

When I was a young boy in private grade school we had to study Latin. I hated it which has resulted in my avoiding the study of genetics as it starts getting into the Latin names. I understand the need for them, but that doesn't change my attitude towards the language.

I have spent the better part of close to the last 2 decades breeding plecos. For the most part it has been the Hypancistrus and then mostly those from the Big Bend of the Rio XIngu. The potential for finding natural hybrids there is not so difficult. I have long believed that the L236 is one such fish.

Throughout the years of working with the plecos one rule has been in place the entire time. I only do species tanks. There are other reasons for doing this besides protecting the genetics involved. My breeding tanks hold not just one species of pleco, but just one species period. There are no other fish or any kind at all in the tanks.

If one deals with plecos and to a lesser extent cories, we are familiar with the L and C numbers. My feeling is that there are way more L-numbers for unidentified plecos than there are of C-numbers. But I could be wrong.

If the common names of fish were not being easily shared by completely different fish, it would make them more useful.

 

[Naughts]

so to specifically answer my op...
Corydoras aeneus, are the genus & species of my albinos cory's... my black ones are Corydoras schultzei... so they are both Corydoras Genus, but different species... so they can't inter breed ???

but if I were to add Corydoras aeneus, non albino, those could breed, as they are the same genus, & species, but are different varieties???

Yes.

https://www.planetcatfish.com/media/corydoradinae_lineages(2020).pdf

IIRC, Byron said that cories in the same lineage could possibly interbreed if they were kept singularly or in same-sex small groups. Aeneus and Schultzei both seem to be lineage 7 so your pairs could fall into this criteria. If you had 5+ or so of each species hybrids wouldn't occur.
But I didn't read Gary's new info on cory classification so this may well be super-ceded.

 

[Essjay]

Corydoras aeneus and C. schultzei are now both in the genus Osteogaster. I must find Byron's post on lineages.......




@Magnum Man I forgot to mention that if you write about several species of the same genus in the same sentence, the genus (first part) name should be written in full but the following names can have the genus abbreviated to the first letter as above ^




(Have I mentioned that I studied zoology for a year at university and we spent a whole term on taxonomy)

 

[Essjay]

I've found a post with a confusing diagram, but the colours used in the diagram do show the 9 different lineages of the fish that were in the genus Corydoras. Cories in different coloured branches won't hybridise but those in the same coloured branch could possibly hybridise.

No. Each species within each distinct lineage has evolved from the same common ancestor, not from species within the present lineage. An evolutionary lineage is a line of descent of a taxon (which may be a species, genus, family) from its ancestral taxon. The Callichthyidae family has two subfamilies first defined by Hoedeman in 1952, the Callichthyinae and the Corydoradinae; the latter contains the Corydoras, Aspidoras, Schleromystax, Brochis genera which together hold some 90% of the species in the entire family--170 described, not including the dozens of "C" and "CW" number possible species. Alexandrou & Taylor (2011) suggest that the group are likely very old, with a fossilized Corydoras (Corydoras revalatus) described from the Maiz Gordo Formation of Argentina (Cockerell, 1925), dated from the late Paleocene.

The first Corydoras species described in this genus was C. geoffroyi Lacepede, 1803 and he designated this species as the type for the new genus. C. aeneus (Gill, 1858) was originally described as Hoplosoma aeneum by T.N. Gill in 1858; I believe it was moved into Corydoras by Nijssen and Isbrücker (1980). Unless there is another species I am not aware of that predates, once the lineages are sorted out, the actual genus Corydoras will have C. geoffroyi as the type species, since the rules of the ICZN require that the oldest name assigned to the genus must prevail. This is lineage 1 and as I say it retains the genus name.

The "aeneus" group of species are lineage 7, and will have a new genus name, presumably (Alexandrou & Taylor, 2011) Osteogaster (Cope, 1871) with C. eques Steindachner, 1876 as the type species for that genus; since the genus name will change, the species will then be known as Osteogaster eques (Steindachner, 1876). The parenthesis around the describer's name signifies that the genus has changed since the species was first described by that individual.

I have a chart showing the phylogenetic relationships of this subfamily; I must give credit properly, and I believe it came from Ian Fuller.
View attachment 134332

 

[Magnum Man]

is there a problem with me doing this??? diagram credited to Ian Fuller

 

[Essjay]

No that's fine, just edit the post to give credit to Ian Fuller

 

[DoubleDutch]

A lot of Corys crossbreed indeed depending on the lineage they are (were) in. Pandas are the most notorious ones.

 

[Mr Limpet]

I accidentally crossed Corydoras sterbai with C. metae. The offspring looked like metae with some black markings on their sides and the orange ventral fin spines of sterbai.