Longnose Corydoras & their...aggression?

[HaakonH]

I'm surprised to find very little information on the topic of longnose Corys and their temper, so I'm going to go for the easy way and just ask people here. I have both heard, read and to some extent also experienced that they can be more unpredictable in their behaviour than the shortnosed ones.

It seems longnosed forms are no schooling fish like the shortnosed forms, although they do blend in with schools of similar looking shortnose species. Yet they obviously manage to breed and maintain their own kind in nature. They obviously breed in captivity too, so apparantly some keepers succeed in keeping schools of longnosed forms as well...

Is there really any truth to this, or are these just coincidences? Are longnose species actually borderline aggressive and harmful to each other and other close relatives? Is this a male thing? A breeding thing? Does the same apply to every longnose form or are some as peaceful as we've learned to expect from Corys in general?

I would love as much input as possible from those with experience on this matter, hopefully the topic will cover several species so we can get an idea of how they vary in behaviour!

Haakon

[The.Dark.One]

If by longnose you mean what I would call hognosed (the acutus group etc) then the only ones Ive kept are sarareensis. The males were very aggressive with each other and would use their bristly pectoral fin spines and cheeks to spar with each other.

[ars]

Very good topic, Haakon!

My C. cervinus are actually very aggressive towards each other. This behavior definitely becomes more intense a few days before spawning. In general a dominant female will constantly chase and attack other females of the same species as well as corys of other species (mine live in the same tank along with C. areio and still don't mind breeding regularly). Same for males. This chasing can be quite intense and I had a case when one of the chased females got killed. I've noticed the dominant pair occupies most of the tank space, whereas other corys try to hide and stay inactive most of the time. Biology is amazing!

Cheers,
Rob