L128 sexing

[Cristoffer Forssander]

Hello!

I would like to have a second opinion on these two L128s!

I thinkt the left is male and the right one is a female







Male

Female

There isn't much differences in the head, but perhaps the "females" head is a bit shorter. The males fins seemes longer and thicker.


Anyone for a second opinion?


Cheers
Cristoffer

[MatsP]

I'd say two males. I'm not 100% certain, but 90% sure.

--
Mats

[bigbird]

agree with Mats. cheers

[Cristoffer Forssander]

Ok. Perhaps you're right! But I can see some differences in the pectoral fins...
I was examing a dead L128 a few days ago and she had egg inside her, and had the same bodyshape as the one on the left...
Very difficult fish to sex....

Cheers
Cristoffer

[Lygen]

i can see some differences too, but that head shape makes me agree with Mats

yet maybe we'r wrong, as you said its a very difficult fish to sex...

[MatsP]

Besides head shape, the odontodes on the "less clearly male" makes me think male. But going by my usual luck, you'll probably have them breeding in no time... ;)

(By the way, the ventral fins look a bit different as well)

--
Mats

[Andypex]

Such difficult fish to sex, I have 2 large L128, much the same as these 2..... 1 VERY obvious male and 1 i thought was a female as it had minimal odontode growth, the angle of its head slope was different (not as steep), and its pectoral fins were less defined with a thinner leading ray.
I had the fish vent sexed by someone with (alot) more experience than myself and we came back with the verdict of 2 males.

It has been suggested that where 2 males exist in the (relatively) small confines of a tank (i.e no matter what size the tank its alot smaller than the river) 1 of the fish becomes a "sub-dominant" male and basically looks very similar to a female as its features are less defined.

That said...... i have never actually seen a female

Andy

For what its worth, my opinion is that these two are also 2 males.

[jvision]

It does seem to be quite difficult to sex these guys. Going over the pics in the Cat-eLog, it would seem that in venting the fish, it looks as if the genital papillae are visible in the female, but not in the male. Cristoffer, since the only pic in the Cat-eLog of the vents is credited to you, do you remember if those fish had just recently spawned? I have experience venting cichlids, which is a lot easier after the fish have spawned (female vent is larger after passing eggs) - would that be the same as these guys?

As for the original topic and the pics labeled in the Cat-eLog, I'd have to guess at both fish being male. From other pics of these fish, females do tend to look like they have a longer, more pointed head. These two fish both have similarly blunt heads. Does that make sense??

[Cristoffer Forssander]

Hello!

These two (first pair photo), hasn’t been together at all, just for the photo sessions. I've kept most of them separated or in very large tanks.


The pair on the Cat E log had been separated for some time and the female had been in a tank without develop spines as well, but they clearly differ in head shape.

As said, I open the inside of a dead L128 female just weeks ago, with eggs inside her. She is identical to the fish on the right (the pair photo), looking at size, lengths of the fins and odontodal growth.


For some reasons, and I've seen this in other plecos as well, the head shape, can differ a lot among females.


These three females have been alone in a 500 liter tank for some time. None of them have developed spines.
But from experience with L200 low fins, females can look very much like males when bigger. I had three dead L200 a few years ago. I thought all where males, but they where all females. Now I have I new group of large L200s and the females looks very male like.... I can see if I could take some photos of them senes they are not in a breeding tank for the moment.

Here are 3 of my other females. I'm positive about them being females, despite differences in head shape.

Female 1. 13 cm SL


Female 2. 14 cm SL


Female 3. 14 cm SL (I think this is the female on the cat E log, but I have another one that’s has this pointy head) But they had not spawned close to this photo event. I think it was almost a year after.



Note that the dead female that I examined didn't have this head. Female 3 had made a spawning once but the father did eat the eggs.

The pair on the photo is a few cm bigger than the once above. I agree on the issue with subdominant males but I don't think this explains the shorter pectoral and pelvic fins, but it could explain the lack of odontodal growths.


I think perhaps the sexual differences in these fishtypes could be less than in other species and that there are just very small visible differences between the sexes. This makes it difficult.

I find these differences to be similar in L239 for example.
Just a bit shorter head, bit shorter pelvic and pectoral fin. But this is only me thinking, I'm not sure.

Pair of L239 (male left, female right)

[OlePaulsen]

see under if the females are orange yellow under ? isn't that a way to sex this species also ? i had a adult pair long time ago, and there was the color under different. Maybe just on mine?

[Cristoffer Forssander]

Yes, I also experienced the yellow belly among females. I never seen yellow bellys in males, but I've seen to few to know if this is a common sexual differences... but perhaps this could be a way to tell the sex. But it should also be considerd when sexing L128s- every key to tell the sex should be used!

Do you have photos of this pair?


Cheers
Cristoffer

[GirlsGotFisshues]

So do females never have any odontodes, or do they just have less developed odontodes?

I have one that was the sole L128 in its tank for a long time and is shaped slightly differently than the other I have that is definitely a big male who thinks he's a stud but looks absolutely absurd swimming around with plants stuck to his pectoral velcro. They've been together for about a year, and recently moved to a larger tank. After the move, "Blue Meanie" began chasing "Ms. Meanie" relentlessly, to the point of actually leaving abrasions on her side and head. I've separated them at this point.

Also, dogs are f*cking disgusting. Mine just dropped a ball in the toilet, then took it out and dumped toilet water everywhere. Anyone want a disgusting, but lovely working line GSD? (J/K, I think).