The Puffer Forum

Hi all,

I wonder if others have noticed this difference between males and females irrubesco: I have a couple, and they exhibit the usual differences:
[*] Male is significantly larger (maybe 30% longer), and more muscular/boxy, especially the tail just before the caudal fin is much thicker. His outlne shape is quite different, less rounded and the anal region protrude a little bit
[*] Colors differ of course, male is much less spotted, more grey tone, and have a uniform belly without black squiggles. Fins are very different in color, male got red tail and dorsal fin, slightly red anal fin. the tail/caudal have a white thin border on top and bottom, that looks a little rough. The fins except the caudal seems smaller (at least compared to the body size) than that of the female. Female have transparent fins except for the caudal that is spotted/patterned brown
[*]Male can change his colors more: he can become almost fully dark grey/black when upset, can shown his light stripes more or less, and can show a red line on his belly, more or less thick, more or less intense. Female can get vey dark (her back, at least) or very light, and can show a lot of black squiggles o her belly or make it almost dissapear
[*]Male can show the typical ventral (often) and dorsal (much less often) ridges of the carinotetraodon species. When he show his rigdes, it is can be discrete or spectacular, and he often show the red line simultaneously.

Thats for the well know differences, but in addition to that my male also have skin wrinkle on his belly: two lateral wrinkles under the jaw, parralel to the body and 45 degree, between horizontal and vertical plane, and often one or two small wrinkle perpendicular to the body, also under the chin. It looks a little bit like a double chin, maybe I am feeding him too much
Those wrinkle are not always visible, but there is no similar thing on the female belly, her skin is smoother and thighter....
I have never seen this particular dimorphism described before, I wonder if others have noticed it...or maybe my male is an old wrinkled guy?

Differences of the sexes are quite obvious & shown in our Pufferpedia, found under the Learn tab.

Pufferpunk wrote:Differences of the sexes are quite obvious & shown in our Pufferpedia, found under the Learn tab.

They are, and can be clearly seen on the photo.....except for the belly wrinkles. This has never been mentioned on any article I have seen on red eyes, irrubesco or others, and can not be seen on any photo I've found on the net. To be clear, the wrinkles are not the keel (the ridge that can be extended on the belly and (less) on the back, that give the name to the carinotetraodon family). They are not at the same place or have the same alignment, are not as long and not as pronunced, and do not seems to be under voluntary/muscular control). Just wrinkles, but not the bluish fine eye wrinkles of the male travancoricus either

I will try to take a photo tonight, not sure I manage as both my male and female are camera shy. Not simply shy, they come and beg continuously when they see me....but as soon as I put the smartphone or mirrorless in position for a picture, it seems they do not see me as a friendly food source but as a possibly threatening predator lol

I still think these wrinkles are part of the keel or to be more specific: Skin which is smooth when the keel is erected, but a wrinkle when it isn't. But let's see, what your pictures show. I can compare it to pictures of my former male C. irrubescos.

gkai wrote: I have never seen this particular dimorphism described before, I wonder if others have noticed it...or maybe my male is an old wrinkled guy?

Could well be unique to your specimen, or particular to the population from which it was collected, or indeed something that occurs among some but not all C. irrubesco and precisely as you suggest, it's there, but not often/ever commented on.

Males and females of this species are so obviously different, that it's possible nobody bothers to use the more subtle differences between them where the obvious differences will do. On the other hand, telling apart this species from C. lorteti seems to challenge wholesalers and retailers all the time! (It seems very common for retailers in the UK to get sent mix batches of C. irrubesco and C. lorteti.)

Cheers, Neale

Corvus wrote:I still think these wrinkles are part of the keel or to be more specific: Skin which is smooth when the keel is erected, but a wrinkle when it isn't. But let's see, what your pictures show. I can compare it to pictures of my former male C. irrubescos.

You may be right, I've got 2 pictures that shows the wrinkles quite clearly (the lateral one and the ventral one, perpendicular to the keel). Sometimes I can see 2 ventral wrinkles, but here my little guy was slightly nervous from the mirrorless, and started to erect his keel, which indeed makes the wrinkles less obvious.
BTW, it was not easy to take the pictures: with the black mirrorless camera and a slight zoom, it was ok...But my first attempt was with my phone, whith a wider angle lens...Not good, he started to panick, turned dark grey and made a high speed escape (when they use the caudal like normal fishes, intead of helicoptering with their four small fins). They really don't like my phone, even without flash

Also, I think that the spot on the left is a bite from my female, it was not there yesterday and she was way more nervous tonight, I witnessed two attacks. And she was slimmer too...maybe some eggs are in there? but they will not last long with the guppies :'-(

Great shots of a difficult to photograph species!
Yes, that is a pufferbite. Lovebite???

Pufferpunk wrote:Great shots of a difficult to photograph species!
Yes, that is a pufferbite. Lovebite???

hehe it really does look like one, doesn't it? But puffers are more rough than us, they use their teeth lol

They do use their teeth but puffer skin is rubbery,

Wow nice pics yeah that's what I'll call the bite marks on my turgidus puffs, lovebites! Lol