Rocio Octofasciata, Rocio Ocotal, And Rocio Gemmata

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I believe you are correct. There are only 2 rocio species now. Spinosissima was archocentrus moved to rocio. The CA classification changes w/ the wind lol.
I was gonna say that didn’t look like rocio. Sometimes trade names feels easier…at least it is generally consistent (if not wrong) lol
Makes you wonder if any of the jacks running around today are actually of the other species, or hybrids. Similar to how Midas and devil got mixed up cause nobody could tell.
 
It's not possible to know. I can't imagine R. spinosissima breeding with R. octofasciata (or R. ocotal, which CRC recognizes for now). They're just way too different fish in terms of size, behavior, etc.

As for R. ocotal and R. octofasciata (and the fish formerly known as R. gemmata) absolutely they would cross. Heck, they're probably just geographic variants of the same fish.

So how to know if you have "pure" Rocio? Get fish of known provenance.

I was gonna say that didn’t look like rocio. Sometimes trade names feels easier…at least it is generally consistent (if not wrong) lol
Makes you wonder if any of the jacks running around today are actually of the other species, or hybrids. Similar to how Midas and devil got mixed up cause nobody could tell.
 
I was gonna say that didn’t look like rocio. Sometimes trade names feels easier…at least it is generally consistent (if not wrong) lol
Makes you wonder if any of the jacks running around today are actually of the other species, or hybrids. Similar to how Midas and devil got mixed up cause nobody could tell.
I would bet so. I have a picture saved on one of my phones of a jd that has so much red in it I thought it was photoshop. Now I know it's whichever catch location that has the red in. Can't Geneve the name atm. Be pretty cool to have a pair to breed for that stronger coloration
 
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Trade names really aren't easier because there is no standardization in them. Anyone can make up any name and sell a fish under a trade name. It's why the genus Heros is a mess from a commercial standpoint, and why people endlessly argue about what a "green terror" is, and why a ton of non-Geophagus fish are called geos.

I know it frustrates people when scientific descriptions change, but as our technology improves, we are able to drill down into the actual relationships between genera and classify the fish in a way that makes some scientific sense. It used to be based on physical characteristics like appearance, jaw structure, teeth, etc. Now we're adding the genetic element to it through DNA analysis which further clarifies (and sometimes invalidates) things.

In the case of Rocio, it looks like the new species descriptions were not erected based on any kind of DNA research and the authors even included the caveat that they could all be geographic variants of the same species, which is likely.
 
Well said Ryan. Apparently the site I was on hasnt caught up with times. So there is only 2 species in the rocio family now? Did I read that right? Or 2 new species? What is the best place to go for this Information and to be able to keep up with the most recent changes/additions being made? I usually follow Chris Biggs for most of the stuff but he doesn't always cover everythingin interested right at that moment
 
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I use Cichlid Room Companion. They list octofasciata and ocotal as valid species, and gemmata as a junior synonym of octofasciata. Here is what they say about ocotal which seems to be the basis for leaving it as a valid species:

Diagnosis: No unique autapomorphies, but distinguished from the other Rocio species as follows: abdomen reddish in life (vs. whitish–greyish); pelvic fins usually falling short of anal-fin origin (vs. nearly always reaching caudad beyond 1st or 2nd anal-fin spine); lingual cusp in lower symphysial teeth absent (vs. usually present); isolated secondary pores (i.e., in addition to the pored scales on the extended caudal fin) present (vs. none or sporadic); spots on scales on side of body absent (vs. present); dentary pores 4 or 5 (vs. always 4) (From Schmitter-Soto, 2007).

Type locality: Laguna Ocotal, Chiapas, Mexico.

Distribution: Probably endemic to Laguna Ocotal, a rather isolated, highland water body in the Lacantún-Usumacinta drainage, Chiapas, México.
 
When I snorkel different Cenotes in Mexico, there were slight color differences in one JD to another one cenote to another.
The Cenotes tend to isolate populations, and because one cenote may have lighter color rocks, or more or less vegetation, a certain population may select for certain colors due to terrain. It is the same for Matayheros uropthalmus, but a slight color difference may not call for populations to be different species. If terrain is light the lighter colored fry will survive
In one centote, a JD may be quite blue.
1635365676706.png
In another a couple clocks away, an individual may be more brown, or both colors may be mixed in the same area.
I remember when Don Conkel discovered a very red version, in a single isolated Cenote.
In one Cenote, the M. uropthalmus may be very light in basic color.
. 027 zps4b102ffd
In another where jungle provides more constant shade, uropthalmus may present darker.
Azul imovie edit
This not only goes in Cenotes.
1635366020177.png
Above, Chuco intermedia from one tributary.
Below another Chuco intermedia from a different tributary
1635366095188.png
Beyond color, topography may even select for a slightly different shapes, of the same species

1635365600469.png
 
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