# Eggs of P. nattereri and S. spilopleura



## hastatus (Jan 16, 2003)

First, I wanted to discuss the egg type you will encounter. By knowing what the egg consists of will help you provide adequate conditions so that they hatch properly. I chose the 2 above species since they are the most researched. S. spilopleura would also include S. maculatus since both species are close. Some of you may have read where I stated that P. nattereri and S. maculatus are the rabbits of the pirana world because they are year-round prolific spawners. The fish equivalent of egg-laying cichlids and live-bearing guppies for those attempting to breed them. That does not mean they are an easy fish to breed, just that it is not as difficult as you may think. I will be posting a picture later of what the surface of S. spilopleura egg looks like under scan.

As strange it this may sound they are honey-combed in appearance. These pores are wide, polygonal in shape. This makes them adhesive. As some of you know, S. spilopleura gives parental care to its eggs and is a multiple spawner. Submerged plants and roots is the main substratum for the eggs for wild as well as aquario specimens. P. nattereri also exhibits this trait in the eggs. Currently unpublished work on S. brandtii suggests this pattern is characteristic of the group. It is believed that this arrangement allows better oxygenation of the eggs. You may note that sand and rocks sometimes are stuck to the egg. That is because of how the egg is shaped (the honeycomb pattern) and the mucus adhesive in those cells.


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## mashunter18 (Jan 2, 2004)

Very good info with a pictutre


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## MR HARLEY (Aug 12, 2003)

Keep It coming Frank


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## killum (Jun 3, 2004)

Great info!!!!


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## Lonald (Jan 10, 2004)

interesting, good work


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## Lonald (Jan 10, 2004)

what are the chances of 2 macs breeding, if they are the only 2 in the tank?
and they are male and female


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## hastatus (Jan 16, 2003)

> Lonald Posted on Oct 13 2004, 04:16 AM
> what are the chances of 2 macs breeding, if they are the only 2 in the tank?
> and they are male and female


50/50 chance, assuming they don't bite themselves in half. Problem with Serrasalmus sp. and in particular this one, they do extremely heavy biting (rough sex) and you have to be careful knowing when to separate (if needed). The trauma to the body is secondary to the problems of them getting so wild that they actually cause permanent damage. Fin loss and minor body bites regenerate, including some around the mouth. Just be sure there are areas the one that is being beaten up more (usually the male) has a place to hide if things get too bad.

I'm in the process of gathering together some science data on actual breeding of this species and a few others that will help members here. The only real problem I have with publishing much of this material is it appearing in other forums without credit from the source.


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## hastatus (Jan 16, 2003)

Here is a link to breeding S. spilopleura.

And a new link to breeding S. maculatus by Hiroshe Azuma.


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## Lonald (Jan 10, 2004)

thankyou, great link


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## mantis (May 16, 2003)

great articles, very interesting! Thanks frank


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## Daywalker (Aug 15, 2004)

great info frank


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## rbp 4 135 (Mar 2, 2004)

great info and thanks again


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