Sex And The Single Sewellia
Posted: Sat Apr 01, 2006 5:51 pm
Ok, OK....I know I've been a bad boy today regarding thse guys. It is April 1st after all
Anyhow, I did remove the slate from the tank and replace it with another algae covered pebble, plus I did a water-change on the tank also. While looking at the fish, I noticed something that initially alarmed me. Bear with me.....look at these pictures carefully. Look at the first few pectoral fin rays particularly.......
Munching on the algae pebble.....


Lounging on driftwood.....


Nothing particularly unusual.....

Front edges look smooth in this pic....

Different fish.....still nothing out of the ordinary......

Another fish.....look carefully at this one's fins......

Looks different eh?
I was looking at the fish I have always felt was a male because of its somewhat slimmer appearance. I got a shock. I thought I could see a fungal growth on the leading edges of the pectorals, but kind of "on top" of the fin......like so.....

Note tubercules around leading edge of nose....

Trick of the light....up close it looks like this...



Almost like the rays are somehow raised up off the fin compared with all the other 4 fish.
Here "he" is sitting with another one.....

This is the killer shot that really shows the difference in the fins.

It looks as though there are some raised tubercules near the fin base at the front. This would be consistent with tubercules mentioned in the original description as a characteristic of sexual dimporphism. Other factors are to do with more minute differences of tuberculate sizes.
So....based on this fish's appearance being different from the other's and my experience with sexual dimorphism in Pseudogastromyzon cheni, I have to conclude that this is probably a male, and the fact that it is showing sexual characteristics certainly raises the possibilities of these guys breeding. Having a male and 4 females would be quite a sweet combination. It's possible of course that some of the others might be immature males not showing any characteristics, but their slight extra plumpness leads me to doubt that.
Fingers crossed......
Martin.

Anyhow, I did remove the slate from the tank and replace it with another algae covered pebble, plus I did a water-change on the tank also. While looking at the fish, I noticed something that initially alarmed me. Bear with me.....look at these pictures carefully. Look at the first few pectoral fin rays particularly.......
Munching on the algae pebble.....
Lounging on driftwood.....
Nothing particularly unusual.....
Front edges look smooth in this pic....
Different fish.....still nothing out of the ordinary......
Another fish.....look carefully at this one's fins......
Looks different eh?
I was looking at the fish I have always felt was a male because of its somewhat slimmer appearance. I got a shock. I thought I could see a fungal growth on the leading edges of the pectorals, but kind of "on top" of the fin......like so.....
Note tubercules around leading edge of nose....
Trick of the light....up close it looks like this...
Almost like the rays are somehow raised up off the fin compared with all the other 4 fish.
Here "he" is sitting with another one.....
This is the killer shot that really shows the difference in the fins.
It looks as though there are some raised tubercules near the fin base at the front. This would be consistent with tubercules mentioned in the original description as a characteristic of sexual dimporphism. Other factors are to do with more minute differences of tuberculate sizes.
So....based on this fish's appearance being different from the other's and my experience with sexual dimorphism in Pseudogastromyzon cheni, I have to conclude that this is probably a male, and the fact that it is showing sexual characteristics certainly raises the possibilities of these guys breeding. Having a male and 4 females would be quite a sweet combination. It's possible of course that some of the others might be immature males not showing any characteristics, but their slight extra plumpness leads me to doubt that.
Fingers crossed......

Martin.