Fishing trip puzzles

Discussion about cichlids from Central America
User avatar
chc
Posts: 182
Joined: Fri Jan 02, 2004 4:51 pm
Location: Virginia Beach, VA USA

Re: Fishing trip puzzles

Post by chc » Mon Jun 14, 2010 10:32 am

Great update. Very interesting, but it doesn't yet meet the standard required for deeming the fish margaritiferum (or a distinct species at all). Perhaps some samples could be provided for an official description and DNA confirmation? It seems there's a very good chance you have something special!

I'm not yet ready to rule out the likelihood the fish is a naturally occurring hybrid. There have been many of those before, and some were "described" as species before their true identify was revealed. It seems that you'd have seen many more of those fish over the years if it were a viable species. I certainly could be wrong though (I hope I am!), but it's not like these fish are in a previously unknown body of water. The lake has been collected and fished constantly for decades.

I find it interesting that DC told you he collected that fish in 2005. In a 2009 correspondence he made no mention of that:

"Thanks for your e mail concerning A. margaritiferum. The Amphilophus group of cichlids was originally referred to as Astatheros Pellegrin, 1904. In 1966, Dr. Robert Miller restructured this large group and named it Amphilophus. In the 1997 work, Molecular Systematics of Middle American Cichlid Fishes and the Evolution of trophic-Types in 'Cichlasoma (Amphilophus)' and 'C. (Thorichthys)', Roe, Conkel, and Lydeard recommended that the substratum-sifting clade of the section 'C. (Amphilophus)' be placed in the resurrected genus Astatheros.
In January 1983, Dr. Paul Loiselle, Vann Mitchell and myself collected 6 specimens of the fish pictured, A. margaritiferum, in Lago de Peten Itza on the island of Flores. The photo on my website is one of those six specimens. Mr. Salvin collected one 6 1/2" specimen in 1862 from this same lake in Guatemala. This specimen is located in the British Museum of Natural History. In Dr. Guenther's work on the fishes of Central America, there is a line drawing of that fish which I have attached. C. Tate Regan's 1906 paper, Biologica Centrali-Americana, a good description of this fish is given (see attachment). Salvin's, Guenther's and Regan's works very closely describe the fish I refer to as As. margaritiferm. While I cannot say with 100% certainty this is the exact same fish, I am not an icthyiologist, I am quite confident it is. I do know for a fact it is not a hybrid. All 6 wild extracted specimens were identical as well as their offspring. Why these so called "arm chair experts" choose to beleive otherwise is beyond me, but perhaps it is because they were not as fortunate to locate or collect it or because I am a cichlid farmer. No other expedition by any one has produced a more similar specimen to that of Salvin's than mine. In addition, in July of 1989, Dr. Robert Miller personally looked over this group of fishes on my Tampa farm and also felt it to be the legendary A. margaritiferum.
Unfortunately, this population of fish is no longer in captivity. I have a farm in Frontera, Guatemala and have made 3 expeditions to Lake Peten since 1998 for more broodstock with no luck. I hope I have enlightened you with the facts.

Kind Regards,
Don Conkel"

User avatar
chc
Posts: 182
Joined: Fri Jan 02, 2004 4:51 pm
Location: Virginia Beach, VA USA

Re: Fishing trip puzzles

Post by chc » Mon Jun 14, 2010 10:41 am

And another 2009 quote from Conkel which doesn't make any reference to a 2005 collection of the fish in question.....

"We collected the fish in question as juveniles (2"+) amongst 400-500 other extracted fishes. We did not know exactly what we had at the time of capture. We shipped them back to Tampa, placed them into a grow out pond and harvested them later in the fall of '83. Only then, was it apparent we had something different and unique. No dna studies were being made at that time by anyone. That technology came about years later, in the early 90's. The first dna papers about CA fishes were produced by Roe, Conkel and Lydeard in 1996.
Unfortunately, we lost this species in the freeze of December 1989. Only one 8-9" specimen survived"



I know DC isn't fond of me questioning the inconsistencies in the margie story, but there are too many to ignore. It's up to the claimant to prove that the fish is legitimate. So far, I'm not convinced. That doesn't mean I want to disqualify the very interesting discussion so far. I hope we can continue this topic to its end. It would be terrific for you two to have found a long lost species!

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Mon Jun 14, 2010 11:56 am

I am very interested in what Don Conkel says. He appears as an expert in very many taxonomic histories. He is obviously a very busy man and to retain in memory everything that has occurred over many years would be impossible. Until I looked up my computer files on the March trip in question my memories were very blurred.
With regard to DNA, every cichlid found in the Lake would need to be on record. Both Don and I completely ignored these fish when they were caught. I actually thought they were T affinis, which we catch constantly. It is possible other collectors have had the same experience and they collect but do not photograph every capture.
There are other species in the Lake, not cichlids, which are almost impossible to find. I recently stumbled on the Peten Molly over which there is another controversy.

I have the complete re-description by Regan in front of me. This agrees in all respects with the several photos of the fish that I caught. The Meristics were performed by Carl and Laura Hubbs, this I have not checked nor the relative measurements.

When a fish fits the official description why are we postulating hybrids?

I have clearly illustrated, where possible the description of this cichlid. I am very puzzled by your negative attitude based on supposition.

User avatar
chc
Posts: 182
Joined: Fri Jan 02, 2004 4:51 pm
Location: Virginia Beach, VA USA

Re: Fishing trip puzzles

Post by chc » Mon Jun 14, 2010 12:18 pm

John Heaton wrote:I am very puzzled by your negative attitude based on supposition.
No negativity was intended -- just a healthy scientific skepticism. There's no other agenda here.

Regarding one's ability to remember everything that's occurred over the years, I agree. That would be impossible. However, I don't think it's a stretch to expect someone to remember collecting a rare or extinct fish within one's lifetime, much less after just a handful of years.

Uncommonly occurring hybrids have been represented as new species before (only to be proven otherwise later), and some hybrids aren't that hard to find (e.g. the unfortunate current state of labridens). Of course, it could very well be the case that this is indeed a distinct species and is just hard to come by. I'm not trying to be definitive either way --- just discussing the issue fully. You have to accept the at least the POSSIBILITY that the fish in question could simply be a hybrid of native species that happens from time to time (just as I accept the alternative possibility). That would explain the rarity of its collection. Explaining the cryptic nature of a rare/nearly extinct species is more difficult (but possible).

With respect to the fish fitting the the official description, have you done fin ray counts, etc?

I'll say it again. I hope this is in fact a distinct species! That'd be terrific!

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Mon Jun 14, 2010 2:04 pm

With respect to the fish fitting the the official description, have you done fin ray counts, etc?

If you look at the annotated photo you will see that the Dorsal fin rays are numbered. I also mentioned that the position of the vertical bands coincided with the numbered rays as described by Regan.

User avatar
chc
Posts: 182
Joined: Fri Jan 02, 2004 4:51 pm
Location: Virginia Beach, VA USA

Re: Fishing trip puzzles

Post by chc » Mon Jun 14, 2010 7:29 pm

Yeah. I saw that and enjoyed the work you did, but I was more referring to comparisons with existing species in an effort to eliminate the hybrid option. I should have been clearer and included that sentence in the "hybrid" paragraph. Sorry for the confusion. My point was to try to find similarities with other fish in the lake.

Regarding the number of bands it seems your fish and Conkel's have a different number. Perhaps they are just more visible in one of the specimens.

An interesting experiment would be an intentional hybridization of native fishes in an effort to produce the "margaritiferum." If one was unable to produce something similar even after a serious effort to do so it would be compelling evidence to support your case. Perhaps a hybridization of melanurus and uropthalmus would produce a similar fish? Uro and a Thorichthys? Perhaps that's a task for us skeptics? 8)

Obviously, a complete DNA analysis of that and the other cichlid species in the lake would be the most compelling evidence of all.

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Mon Jun 14, 2010 7:59 pm

I quote:-
The first bar extends from occiput (top of head) to behind upper margin of gill opening. The second bar extends from Dorsal origin dorsal spines 1 - 5 etc etc

A short broad bar lies over the eye and another on the interorbital space (between the eyes)

A similar species is Amphilophus robertsoni but has 9 vertical bars.

blackghost
Posts: 142
Joined: Tue Dec 29, 2009 4:04 pm
Location: Cumbria, UK

Re: Fishing trip puzzles

Post by blackghost » Mon Jun 14, 2010 8:09 pm

Assuming it is margaritiferum - and I'd like to think it is - I wonder what genus it will end up in. It doesnt quite look like an Amphilophus to me, and even less like an Astatheros. I hope someone will do the DNA work. I hear it is an expensive process?

Whatever it is, it is a VERY beautiful fish. :D
Mark Wright

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Mon Jun 14, 2010 9:34 pm

Thanks Mark
If and when I find more specimens I already have a volunteer to do the work.

Rico Morgenstern
CichlidRoom Expert
Posts: 387
Joined: Sun Jul 22, 2007 4:01 am
Location: Germany

Re: Fishing trip puzzles

Post by Rico Morgenstern » Tue Jun 15, 2010 11:23 am

I am rather convinced the fish in question is the 'legendary' Heros margaritifer of Günther. It agrees well with the various descriptions of the type (Günther 1862, Regan 1905, Bussing & Martin 1974). The most reliable is usually not the original description but the most recent redescription, but in this case all three refer to one and the same specimen, the holotype. No other reliably identified specimens are in the scientific collections, those in Paris identified by Pellegrin (1904) are Astatheros robertsoni, for example. Considerable variation in color and shape can be expected, especially when we compare young with old fish, freshly collected with aquarium specimens or live with preserved fish (or drawings made from them) etc.

However, this does not necessarily mean that it couldn't be a natural hybrid. The apparent absence of this or a closely related form in neighbouring areas and the difficulties to assign the fish to a certain genus are valid arguments. If interbreeding between two sympatric species occurs at all, it cannot be excluded that it had occured before and that Salvin already has collected such a hybrid specimen. The most reliable way to test this would indeed be crossing experiments with the presumed parental species, as chc has suggested, but who would have the capacities? Field observations if the 'margaritifer' breed true or if there are 'mixed pairs' could also help, and of course DNA studies could contribute to solve the problem. However, I wouldn't expect too much from DNA studies alone.

Should Heros margaritifer indeed be based on a hybrid specimen, the name would be invalid. Nevertheless, I hope with you, that this is not so, and that you have simply rediscovered an elusive species!

BTW, some time ago another fish was discussed as possibly identical with margaritifer:

viewtopic.php?f=4&t=4303

I think we can now say, that this is definitely another species, perhaps a geographical race of Astatheros robertsoni or a closely related new species!

All the best
RM

User avatar
chc
Posts: 182
Joined: Fri Jan 02, 2004 4:51 pm
Location: Virginia Beach, VA USA

Re: Fishing trip puzzles

Post by chc » Tue Jun 15, 2010 12:58 pm

Great stuff!

I'd be happy to contribute to the ID process, either by breeding some of the possible parental species (i.e. testing the hybrid theory) or trying to breed true some of the margies themselves. Perhaps I could just defray some of the costs of the process. Just let me know if you need any help.

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Tue Jun 15, 2010 1:53 pm

Very well said, Rico.
The A. robertsoni bothers me as I have never found it. I have spent 4 days fishing in the area where it is supposed to live, the same area where I found the fish under discussion.The juveniles of both have a similarity apart from the bar count. I would look forward to reading one of the descriptions of robertsoni if it is available.

The link was very interesting with many photos. However I noticed that there were a lot of opinions but no detailed examinations of the fish.

My team led by my assistant is scheduled to go looking for the "Margie" tomorrow. I won't be going as I have many other things on my plate including the hand feeding of a baby parrot. They know exactly what they are looking for so I am not needed except as the photographer.

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Thu Jun 17, 2010 10:39 am

Yesterdays unsupervised fishing trip produced a lot of fish but nothing unusual. The final count was;-
5 C.salvini
10 T affinis
5 V.melanurus
4 C. urophthalmus

Although they left at 7 am when the Lake was calm, within a couple of hours the wind increased until the launch eventually
was charging about on the anchor rode. This made fishing very difficult, tangling the fishing lines.
The number of C.salvini caught in this location was very unusual.
Unfortunately the weather this time of the year is unpredictable and sudden short but violent storms in the afternoon are common.
Hopefully we will try again next week.
Attachments
salvini sm.JPG
salvini sm.JPG (225.79 KiB) Viewed 4728 times
affinis sm.JPG
affinis sm.JPG (117.03 KiB) Viewed 4728 times

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Fri Jun 18, 2010 12:59 am

I would like an opinion on the similarity between the following description and the photos.

Seven vertical bars cross the body, the third and fourth are most intense. The first bar extends from the top of the head to behind upper margin of gill opening. The second bar extends from dorsal origin (dorsal spines 1-5) to just posterior to pectoral axis. The third bar crosses the body below dorsal spines 7-11: it is widest at dorsal base, narrows at midtrunk and widens slightly at its termination above and forward of vent. The fourth and widest bar starts below dorsal spines 12-15, narrows slightly at midtrunk and reaches origin of anal fin, The fifth arises below dorsal spines 17-19 and drops to last three anal spines. The sixth arises below last six dorsal soft rays and crosses to last 6 anal rays. The seventh bar is pale and crosses the entire caudal peduncle at mid peduncle. There is a dark region on bar four between the two lateral lines and a corresponding (but paler) region on fifth and sixth bars.
An irregular spot lies mostly on the base of caudal fin.
Attachments
fish 2.JPG
fish 2.JPG (79.45 KiB) Viewed 4705 times
fish 1.JPG
fish 1.JPG (160.18 KiB) Viewed 4705 times

User avatar
River
Posts: 24
Joined: Thu Oct 01, 2009 12:25 am
Location: The Netherlands

Re: Fishing trip puzzles

Post by River » Mon Jun 28, 2010 6:11 pm

The description and the foto's are not similar.

- In the description the fourth bar is the widest one.
- On the foto's the third bar is the widest one.

Of course a description about only the bars is far from complete ;)

Where are the foto's come from?
again I came no further than "one kind of Ampilophus (Astatheros)".

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Mon Jun 28, 2010 8:58 pm

Where are the foto's come from?
The fish in the photos is a Thorichthys. affinis.
Several of the Lake cichlids have very similar bar patterns in certain circumstances, affinis don't usually look like this.
I have some very interesting data concerning the original specimen register at the British Museum. I am waiting for some copies of research made by Los Angeles University. In the British Museum Specimen Register the location where margaritifer was found was left blank. So Gunther surmised, guessed or misread the register. When Regan re-described the specimen he noticed the discrepancy and only stated Guatemala as the location. Previous and following entries were also specimens supplied by Salvin from his Guatemala trip. The actual previous entry had the location as "Isabella" and the entry following margaritifer was Lake Peten.

I suggest you take a look at Don Conkel's Photo Gallery and at the fish labelled as Amphilophus uropthalmus. (His spelling not mine). I have never seen a Mayan Cichlid( C. urophthalmus) quite like this.

http://www.donconkelstropicals.com/Powe ... Safari.pps

User avatar
River
Posts: 24
Joined: Thu Oct 01, 2009 12:25 am
Location: The Netherlands

Re: Fishing trip puzzles

Post by River » Tue Jun 29, 2010 2:44 pm

Yes youre right, now I see. It is Affinis.
I did not recognize without collors ;)

Thank you for the information. Good to hear the Los Angeles University researching
the Margaritifer-story. I am curious to the copies.

The urophthalmus on Conkels side looks a little bit strange indeed (especially the second bar) but
urophthalmus has a big range. Mabybe Concels uro's came from R.Candelaria ore Yucatan.
Anyway, you may expekt a lot of variation within the range of urophthalmus.

blackghost
Posts: 142
Joined: Tue Dec 29, 2009 4:04 pm
Location: Cumbria, UK

Re: Fishing trip puzzles

Post by blackghost » Tue Jun 29, 2010 5:01 pm

To me that Conkel pic is not a urophthalmus. It has uro colours/markings, but it has totally the wrong shape for a uro. The mouth and eye are all wrong aswell. It is the shape of a fish in this puzzle of ours, but not a uro, IMO. Very strange. :shock:
Mark Wright

User avatar
John Heaton
Posts: 181
Joined: Sat Oct 17, 2009 1:14 pm
Location: San Andres, Peten, Guatemala, Central America.

Re: Fishing trip puzzles

Post by John Heaton » Wed Jun 30, 2010 8:21 am

Yes Mark, that is exactly what I saw.
To me it looks more like the margaritifer than the other ones labelled margaritifer.

While I was chatting with one of our ancients, some time ago, he was looking at some urophthalmus in my tanks. He said "Oh yes, Bool (the local name) but sometimes they have a bump on their heads"

All these odds and ends that keep filtering in are keeping me wondering.

User avatar
Alex Odesit
Posts: 1072
Joined: Wed Feb 01, 2006 7:24 pm
Location: Garden State,USA. Odessa Ukraine

Re: Fishing trip puzzles

Post by Alex Odesit » Wed Jun 30, 2010 9:33 am

I've seen several types of wild Urophthalmus in Mexico.
The URO from Conkel's presentation is exactly the shape of the fish I observe in great numbers in cenote Manati (I believe that was a name) by the sea. Manati is deep and clear with brackish cool water and heavy mangers.
The tall bodied and shorter in total lenghts Urophthalmus are from cenote Azul (that's where I've seen them couple of month ago) and probably some others, that I didn't visit yet.
Azul is about 1 hour away from Cancun airport, very shallow, warm and heavy planted, 1.5 km or so from the sea.
Alex

Post Reply

Return to “Central American Cichlids”