Amphilophus citrinellus vs. Amphilophus labiatus

  • We are currently upgrading MFK. thanks! -neo
I'm 20 years late but I came across this in my digging for ways to diagnose the two species against eachother/find ways to identify mutts. I figure (in spite of the fact that it may have been posted elsewhere on this site since this thread) I should contribute (in the event that someone else stumbles across this) that we now know that citrinellum is a social benthic detritivore, while labiatus is a solitary crevice feeding active predator. In my "research" I have found that labiatus has a small upward fold/knob of tissue at the tip of the top lip (even in captive or immature specimens) that is completely absent in non crevice feeding amphilophus. This trait appears to carry down to mutts as well. I will continue my search for any other body proportions that can be used to diagnose the two species externally for the layman.
 

Good luck
 

Good luck
Ah... not sure if you had it in there, but this reminded me to check another paper I've been meaning to read on Amphilophus phylogeny, being "Not a simple case – A first comprehensive phylogenetic hypothesis for the Midas cichlid complex in Nicaragua (Teleostei: Cichlidae: Amphilophus)" by Geiger et al. 2010 (https://doi.org/10.1016/j.ympev.2010.05.015). It states:

"...there is genetic structure within the L. Nicaragua Midas cichlids that is not covered by current taxonomic classification or sample location. Consequently, treating all identified phenotypes and described species as members of a highly polymorphic A. citrinellus does also not reflect the discovered pattern and should be discarded. The prominent basal position of four L. Nicaragua individuals belonging to four different phenotypes might be a consequence of retained alleles common to these individuals whose genotypic similarity is reflected in joint clustering in the Bayesian analysis. However, neither all individuals a priori identified as A. citrinellus nor as A. labiatus clustered according to species assignment or geographic origin of individuals."

"Lake Nicaragua’s species assemblage does not constitute a monophyletic group as it contains the four most basal taxa of the in-group, belonging to four different putative species (Fig. 1). Interestingly, individuals of L. Nicaragua do not cluster according to their geographic or taxonomic identity while in contrast individuals from L. Managua are largely grouped according to their geographic origin within the lake basin – a preliminary indication of restricted gene-flow between populations from opposing shores."

So in short yes we have no clue what any of the midas/red devils in the hobby are even if they are traceable to the great lakes. Disregard my previous statement. Midas/red devil IDing is once again out of my jurisdiction.
 
  • Like
Reactions: RD.
This is why, in my opinion, it's such a boon to have importers bring in F0 (Wild Caught) fish, then breed and distribute F1 fish. All while making their exact collection point known. This way we know what we have.

But anytime we are collecting fish from unknown origins we are risking having hybrids or mislabeled fish.

Having said that, I'm not turning my nose up at every single "unknown origin" Cichlid. Most of the fish in my tanks could be described as such.
 
This is why, in my opinion, it's such a boon to have importers bring in F0 (Wild Caught) fish, then breed and distribute F1 fish. All while making their exact collection point known. This way we know what we have.

But anytime we are collecting fish from unknown origins we are risking having hybrids or mislabeled fish.

Having said that, I'm not turning my nose up at every single "unknown origin" Cichlid. Most of the fish in my tanks could be described as such.
No the issue here is we don't even know what the wild fish are, because there are 8 of them that look exactly the same from two lakes with 4 each. 4 from one lake (lake managua) can only be told apart by the part of the lake they were caught in and the other 4 (lake nicaragua) can only be told apart by genetics. We also don't know which one of those 8 is the true labiatus or citrinellum (respectively, both will still eventually be valid given they're described out of separate lakes and thus represent distinct lineages) without running the genetics of their holotypes because all of them can present as the benthic or thick lipped form. Every other fish this applies yes but hobbyists can't really do anything about Amphilophus.
 
I am most assuredly not qualified enough in taxonomy to speak to the species identification problem that was the topic of this thread, but I will say this. I have been in the hobby for over 60 years, and "back then" what were sold in local fish stores as A. labiatus vs A. citrinellus were two very different looking fish. I remember not liking the labiatus look because I thought the puffed out lips looked weird and the body shape was more elongated. To me as a kid, citrinellus had a more powerful look, with a taller, beefier body shape and "normal" lips. I liked that look and kept a couple in my early years in the hobby, but avoided labiatus. I think the "Mutt" issue is likely the source of the confusion.
 
I am most assuredly not qualified enough in taxonomy to speak to the species identification problem that was the topic of this thread, but I will say this. I have been in the hobby for over 60 years, and "back then" what were sold in local fish stores as A. labiatus vs A. citrinellus were two very different looking fish. I remember not liking the labiatus look because I thought the puffed out lips looked weird and the body shape was more elongated. To me as a kid, citrinellus had a more powerful look, with a taller, beefier body shape and "normal" lips. I liked that look and kept a couple in my early years in the hobby, but avoided labiatus. I think the "Mutt" issue is likely the source of the confusion.
I should rephrase my previous statement given what I know, but the consensus from the genetic data is that the thick lips do not immediately constitute the "labiatus" designation.

There are four distinct lineages of Amphilophus in Lake Nicaragua, and all of them can have a thick lipped "labiatus" and "citrinellum" form. All of these fish are for the most part indistinguishable and can only reliably be told apart by genetics. None of these are actually labiatus though because the original labiatus specimen is from Lake Managua, which has its own set of genetically distinct Amphilophus.

Subsequently we do not know what the "labiatus" or "citrinellum" in the aquarium trade are exactly, even the ones that are stated to be from Lake Nicaragua (which is really the only "locality" of either "species" available in the US aquarium trade right now).

Furthermore we do not know
1. what the "true" Amphilophus citrinellum is unless we look at the genetics of the original citrinellum specimen to see which of the aforementioned four lineages it fits into (though we as aquarists still wouldn't be able to tell because again they are all visually indistinguishable)
2. if any of the Lake Nicaragua "labiatus" and "citrinellum" in the aquarium trade represent this "true citrinellum"
3. whether any given set of aquarium specimens all even represent the same species (because again, all 4 putative Lake Nicaragua species are indistinguishable so we don't know if their wild caught ancestors were even the same species as eachother)

The study that unraveled this used genetic data from several hundred specimens which are obviously not all represented on the tree they show, unless they consolidated the lineages that were really close for the sake of presentation. From what they present though, the true labiatus is a bit easier, as the tree shows the "labiatus" from Lake Managua as being a standalone lineage. Going off of this I would assume that is the true labiatus, but I'll have to look at the full tree with all the hundreds of specimens to be sure.
 
If one reads up on some of the various papers that I linked to in the sticky on this subject, it becomes rather clear that most researchers and collectors back in the day, including George Barlow et al, made some incorrect assumptions regarding labiatus vs citrinellus. Those mistakes based on assumptions carried on for decades, and continue today. The creation of Midevils began in the early 1970’s. Dr. Wayne Leibel wrote about the early collectors in the aquarium trade, which clearly had no idea what they were passing off as labs, or cits, other than their personal observations of body shapes and thick lips, or not. Mistakes were made, everyone knows that, beyond that the waters get rather murky.

As a hobbyist about the best we can do is purchase fish with provenance from a trusted source. Hopefully the fish were collected from the same area, of the same body of water, at the same time. Short of a DNA work up, that should get a person pretty close.
 
  • Like
Reactions: Hybridfish7
Btw…… none of this is late breaking news. lol. All of the above and then some has already been posted and discussed in the sticky on this subject, that I posted back in 2011. Not sure why this old thread got bumped?

If anyone has something new to add, or wants to discuss any of this further, it would probably make a lot more sense to take this discussion back to the sticky thread that I linked to above.
 
  • Like
Reactions: Hybridfish7
MonsterFishKeepers.com