I read through the article which established the monotypic genus Chiapaheros containing only the species grammodes and it seems to me that there is no adequate justification for this - the authors were mainly focused on (re)classification of Herichthys and other species and really did not consider the possible relationship between grammodes and, for example, various Parachromis species (such as dovii). It appears to have been an after-thought - to paraphrase their intent they thought grammodes should not be left in Cichlasoma (which few would argue against). Having kept and bred both grammodes and dovii (and other Parachromis) before, it seems to me that a clear rationale needs to be established to create a new monotypic genus for grammodes. In short, I think aquarists should be skeptical of the "Chiapaheros" designation.
Chiapaheros genus for grammodes
- Thread starter Pronto
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As far as I know, phylogenetic analyzes by Rican et all 2013 have shown earlier that "Heros" grammodes is more closely related to Herichthys than to Parachromis.
Apart from that, grammodes shows no similarities with parachromis that cannot be explained by convergent evolution.
But there are some differences between Parachromis and grammodes
that even speak against a closer relationship, such as the dark breeding colour of the female grammodes and the early visual distinguishability of the sexes in grammodes. Both of these do not occur with Parachromis.
Apart from that, grammodes shows no similarities with parachromis that cannot be explained by convergent evolution.
But there are some differences between Parachromis and grammodes
that even speak against a closer relationship, such as the dark breeding colour of the female grammodes and the early visual distinguishability of the sexes in grammodes. Both of these do not occur with Parachromis.
I really appreciate the quick and detailed response!
The Rican et al 2013 article "Biogeography of the Mesoamerican Cichlidae" didn't offer any specific analysis about grammodes, since it was so broad and comprehensive - but it did show grammodes grouped in a cladogram with Paraneetroplus, Herichthys, and Theraps (the "herichthyine cichlids")- but diverging 20.1 million years ago in Fig. 2! The same results showed the "amphilophine cichlids" including Parachromis, Petenia etc. diverging from the herichtyine cichlids 31.8 million years ago, but the article notes that "the basal nodes of the amphilophines lack significant support." Simply stated, I'm skeptical about the ability of genetic analysis to accurately sort out a cladogram going back that far! Part of my suspicion is based on the tendency of species to exchange genetic material via hybridization as well as via other means (such as viral exchange). Another part of my suspicion is that these authors were primarily motivated by finding evidence in favor of their biogeography model (which admittedly is probably a pretty good model); I'm afraid poor little grammodes was a peripheral topic for them. All I'm really saying is that it would be interesting if the "basal nodes" of parachromis and grammodes could be explored further.... Maybe grammodes was a result of some inter-genus hybrid, after some parachromis "basal stock" crossed some shallow seas and the herichtyine cichlids started looking pretty good to them....
For example, one very legitimate hypothesis for the origins of the coast redwoods is an ancient hybridization event between Metasequoia and Sequoiadendron (although now I'm talking about apples instead of oranges...)
Absolutely there could have been convergent evolution leading to an efficient herichtyine piscivore, however regarding the visual differentiations, please pardon me but those don't seem like very strong arguments. As an aside, I've found sexing very young dovii not particularly difficult!
The Rican et al 2013 article "Biogeography of the Mesoamerican Cichlidae" didn't offer any specific analysis about grammodes, since it was so broad and comprehensive - but it did show grammodes grouped in a cladogram with Paraneetroplus, Herichthys, and Theraps (the "herichthyine cichlids")- but diverging 20.1 million years ago in Fig. 2! The same results showed the "amphilophine cichlids" including Parachromis, Petenia etc. diverging from the herichtyine cichlids 31.8 million years ago, but the article notes that "the basal nodes of the amphilophines lack significant support." Simply stated, I'm skeptical about the ability of genetic analysis to accurately sort out a cladogram going back that far! Part of my suspicion is based on the tendency of species to exchange genetic material via hybridization as well as via other means (such as viral exchange). Another part of my suspicion is that these authors were primarily motivated by finding evidence in favor of their biogeography model (which admittedly is probably a pretty good model); I'm afraid poor little grammodes was a peripheral topic for them. All I'm really saying is that it would be interesting if the "basal nodes" of parachromis and grammodes could be explored further.... Maybe grammodes was a result of some inter-genus hybrid, after some parachromis "basal stock" crossed some shallow seas and the herichtyine cichlids started looking pretty good to them....
For example, one very legitimate hypothesis for the origins of the coast redwoods is an ancient hybridization event between Metasequoia and Sequoiadendron (although now I'm talking about apples instead of oranges...)
Absolutely there could have been convergent evolution leading to an efficient herichtyine piscivore, however regarding the visual differentiations, please pardon me but those don't seem like very strong arguments. As an aside, I've found sexing very young dovii not particularly difficult!
What you say makes sense to me. But I still don't get why they should be related the closest to parachromis an not to anything else. Except that they have a somehow similar bodyshape I don't see any similarities.
The same bodyshape and also the teeth can be a form of convergent evolution which makes them a quite week indication in my eyes.
In lake Malawi it was shown several times that one of the easier ways to find relations or at least strong indications for relations is to look for colour patterns that do not matter for direct suvival.
When I look for this colour pattern in grammodes the first thing that comes to the eye is the red pattern. This red pattern differs in males and females. Males show red dots, females show a red net on the belly. Thats why you can sex a 2 inch grammodes but not a 4 inch dovii (at least I can't).
This colour pattern is very unique and does not show in Parachromis. As far as I know it only appears in C. grammodes an in D. calobrensis.
For me as an interested hobbiest this difference is big enough to consider it as a different genus until I get more information on this. Which we will hopefully get one day.
By the way I would not be surprised im grammodes an calobrensis would be somehow related but were sepparated very long ago. But this is just one of my brain farts...
The same bodyshape and also the teeth can be a form of convergent evolution which makes them a quite week indication in my eyes.
In lake Malawi it was shown several times that one of the easier ways to find relations or at least strong indications for relations is to look for colour patterns that do not matter for direct suvival.
When I look for this colour pattern in grammodes the first thing that comes to the eye is the red pattern. This red pattern differs in males and females. Males show red dots, females show a red net on the belly. Thats why you can sex a 2 inch grammodes but not a 4 inch dovii (at least I can't).
This colour pattern is very unique and does not show in Parachromis. As far as I know it only appears in C. grammodes an in D. calobrensis.
For me as an interested hobbiest this difference is big enough to consider it as a different genus until I get more information on this. Which we will hopefully get one day.
By the way I would not be surprised im grammodes an calobrensis would be somehow related but were sepparated very long ago. But this is just one of my brain farts...
I agree about the resemblance of grammodes and calobrensis, and I would add istlanus to that "resemblance" list. Absolutely there's going to be convergent evolution to make different lines produce species with similar appearance - look at the Tasmanian Tiger as a non-fish example. All the hybridization of cichlid species by commercial and hobbyist breeders (unfortunate in my opinion) shows how it is also possible to cross genus lines, often with fertile offspring. With the prehistoric geological events in Central America causing formerly separated landmasses to join, and in some initial cases perhaps only via shallow saltwater seas, we shouldn't be surprised if some ancient natural hybridization led to the CA and SA cichlids we have today. IMO. Also just one of my brain farts....
Yes, Neetroplus aka Hypsophrys nematopus - always loved those fish! Goes without saying hobbyists don't determine genera - I'm just suspicious of academics making changes and everyone accepting it as though it were an absolute truth. Keep in mind that in academics one has to publish in order to advance one's little career.... Wouldn't be surprised if in another decade or two there will be another radical revision of the former Cichlasoma "genus". Also, keep in mind that years ago there was a breakthrough scientific publication, based on genetic analysis, that there was absolutely no relationship between modern human populations and Neanderthals - only to have better DNA analysis techniques now show that on the order of 3-6% of modern European DNA is Neanderthal, with similar results for modern Asian populations but apparently with Denisovan DNA mixed in. The point isn't the human DNA story - the point is that scientists put forward hypotheses, test them, justify them, but sometimes make mistakes, and sometimes their conclusions are revised or even discarded later with more evidence.
With the ease and economics of DNA sequencing, and testing these days, it is not surprising to me that look alike relationships to determine genus are being debunked.
This testing can directly link, or disconnect previous assertions.
There have been different radiations of basal cichlids to and throughout Central and North America over millions of years, and each can create a number of species adaptations to habitat.
It seems the Herichthyan radiation is where grammodes is found, and grammodes evolved to fill in a a gap other Herichthyines did not.
This testing can directly link, or disconnect previous assertions.
There have been different radiations of basal cichlids to and throughout Central and North America over millions of years, and each can create a number of species adaptations to habitat.
It seems the Herichthyan radiation is where grammodes is found, and grammodes evolved to fill in a a gap other Herichthyines did not.
Agreed!
Despite the "ease and economics of DNA sequencing, and testing these days..." I believe identifying the "right" DNA markers and analyzing/interpreting them is the hard part - but AI programs may take over some of that going forward.
"It seems the Herichthyan radiation is where grammodes is found, and grammodes evolved to fill in a a gap other Herichthyines did not." - absolutely could be - and maybe ought to be the primary hypothesis - but it could also be that a small population of non-Herichthyan predators moved into Herichthyan territory as all these small and large tectonic plates collided (the Caribbean plate, North Andes plate, Cocos plate, South American plate and North American plate) and initially formed shallow salt-water seas before the land truly connected. Such hypothetical non-Herichthyan predatory cichlids could possibly have hybridized with some proto-Herichthyans (for lack of same-species mating partners). Any such hybridization could play havoc with simple-minded analysis of DNA to determine a cladogram. We'll probably never know for sure!
Whatever their cladistic relationships to each other and other CA/SA cichlids - I love Herichthys, "Nosferatu" and "Chiapaheros grammodes" (as well as many other species of the former "Cichlasoma" grand umbrella).
Despite the "ease and economics of DNA sequencing, and testing these days..." I believe identifying the "right" DNA markers and analyzing/interpreting them is the hard part - but AI programs may take over some of that going forward.
"It seems the Herichthyan radiation is where grammodes is found, and grammodes evolved to fill in a a gap other Herichthyines did not." - absolutely could be - and maybe ought to be the primary hypothesis - but it could also be that a small population of non-Herichthyan predators moved into Herichthyan territory as all these small and large tectonic plates collided (the Caribbean plate, North Andes plate, Cocos plate, South American plate and North American plate) and initially formed shallow salt-water seas before the land truly connected. Such hypothetical non-Herichthyan predatory cichlids could possibly have hybridized with some proto-Herichthyans (for lack of same-species mating partners). Any such hybridization could play havoc with simple-minded analysis of DNA to determine a cladogram. We'll probably never know for sure!
Whatever their cladistic relationships to each other and other CA/SA cichlids - I love Herichthys, "Nosferatu" and "Chiapaheros grammodes" (as well as many other species of the former "Cichlasoma" grand umbrella).
Ok - I found what I consider to be a better, more convincing scientific article with the much broader scope I was looking for - the link to that is: https://www.senckenberg.de/wp-content/uploads/2019/08/01_vertebrate_zoology_66-1_rican_1-102.pdf
That very much convinces me of the monospecific genus Chiapaheros and the membership of grammodes in the herichthyines. I must eat humble pie!
Leave it to the Bohemians to explain New World cichlids to me! (The authors are from the Department of Zoology at the University of South Bohemia....)
That very much convinces me of the monospecific genus Chiapaheros and the membership of grammodes in the herichthyines. I must eat humble pie!
Leave it to the Bohemians to explain New World cichlids to me! (The authors are from the Department of Zoology at the University of South Bohemia....)