Pv teaniatus color morphs recognition [long]

[coenga]

Hi to all english speaking (and non english speaking) westphilies around here !

I'm very interested with the Pelvicachromis genus, especially the Pelvicachromis taeniatus complex. My own experience is short as I only maintained and bred the "moliwe" form a few years ago and I'm sure I can find here experienced specialists who will be able to help in a better understanding of this incredible fish.

I've listed 23 different color morphs for this fish...

This is certainly too much for one specie.

AFAIK and things may well have changed since,
in 1980 Loiselle & Castro proposed to split Pv taeniatus in 3 groups

1) Pv taeniatus taeniatus (true taeniatus)
from Nigeria
Etheops river Nigeria Boulenger 1901 "Pelmatochromis taeniatus"

with the possible color morphs
"Nigeria Red"
"Nigeria green"
"cross river"
"Nigeria yellow"
"Calabar"

2) Pv callipterus (Pv taeniatus callipterus) from west Cameroon
Lokoundje Cameroun Pellegrin 1929 "Pelmatochromis kribensis calliptera"

Females have a dark dorsal band just under dorsal fin and a violet belly in breeding mood

with the possible color morphs
"Lokoundje"
"Dehane"
"Moliwe"

3) Pv kribensis (Pv taeniatus kribensis) from south west Cameroon
Kribi Cameroun Boulenger 1911 "Pelmatochromis kribensis"

Females don't have a dark dorsal band under dorsal fin and have a bleu grey "petroleum" belly in breeding mood

with the possible color morphs
"Lobe"
"Kienke"
and also
"Lobe red"
"Lobe yellow"
"Kienke gold"

Other color morphs I listed are :
"Muyuka" said to be close to Nigeria form according to Staeck et Linke, but the collecting site is at 20km from site "Moliwe"
"Makore" close to "Muyuka" according to this forum
"Wouri"
"Nyete"
"Bandawouri"
"Funge"
"Mahone"
"Bipindi"
"Ndonga"
may be more callipterus but I'm really unsure, these localisations are not all on my Cameroon map.
"Nange"
maybe close to kribensis.

Comments now:

Pv taeniatus is a fish that can change of colors in many cases for a single individual (mating courtship, brood care, stress, dominating/dominated, males fighting etc...)
Pv taeniatus males have probably genetical or acquired dominating and dominated color patterns as it is the case in Pv pulcher (which in aparte is another unsolved complex).
Pv taeniatus color is unstable in term of generations. "Kienke" F2 can be of "lobe" colormorphs.
Pv taeniatus has not (in my knowledge) remarkable grey and black marks as it is the case in Apistogramma genus and that permits determination regardless of the colors.
Some color morphs are suspects to be "commercial" colormorphs. More collecting sites, more "color morphs", more rareness, more money...

Then, opened questions

Are there known and acceptable keys for determination in Pv taeniatus that I missed ?
Dorsal and caudal dots are very unstables in numbers.
May be the dorsal band and the belly mating color (callipterus vs kribensis), and what more ?
May I suggest paths ?
length and width of the black crest on the anterior part of the female dorsal fin.
Form, surrounding and distal margin of caudal dots in males.
Throat and anterior belly colors in males (but in which mood ?).

As I previously said, my experience in very narrow, and I've never been sure to have the real "moliwe" form in my tank.

I hope this long topic won't have bothered you, and please forgive my english.

best regards,

Colin
from Orléans (the "old" city on the Loire) France

 

[Randall]

Pelvicachromis taeniatus

Dear Colin,

Welcome! and thank you for your amazing inquiry!! I say amazing because your question(s) are ones that I have been asking myself for some time now.

Yes, Loiselle and Castro proposed "splitting" P. taeniatus into three groups, the "true" taeniatus, kribensis and callipterus. According to Dr. Loiselle, the numerous taeniatus morphs, if grouped, constitute different species. In support of their argument, the authors of the paper to which you refer compiled and published lengthly charts of meristic data and discussed the presence and placement of dark markings, spots and blotches.

When discussing Loiselle and Castro's paper with Dr. Anton Lamboj, University of Vienna, Dr. Lamboj agreed that dividing the numerous taeniatus color morphs into species groups or complexes is a good start.

From what I can ascertain, the process from a hobbyist's perspective can be problematic. Apparently, there is some mechanism in nature that enables syntopic (sharing the same habitat) taeniatus morphs to identify one another and to breed with their own kind. I believe this may go to "natural selection" in the Darwinian sense. In a closed environment like the aquarium, however, that naturally occurring mechanism is lacking. Consequently, it is not uncommon for some taeniatus morphs to interbreed in captivity.

I wish I could answer your questions more directly, rather than beating around the bush, but I simply don't have enough information at this time. May I share the following with you, please?

1. Some of the taeniatus color morphs are man made, i.e., P. taeniatus "Lobe Red."

2. The "true" taeniatus morphs are of Nigerian provinance, yet two Pelvicachromis forms have been fairly recently discovered in Ndonga, northern Cameroon: P. pulcher and P. taeniatus "Ndonga." Historically the range of P. pulcher has been limited to western Nigeria and is replaced by P. sp. affin. pulcher to the East. Do two Pelvicachromis species--pulcher and taeniatus--from the same area in northern Cameroon present an enigma?

Ironically, I will be meeting with Dr. Loiselle on Thursday, 1/16/03, and had planned on discussing the state of Pelvicachromis with him then. One thing is for certain: Pelvicachromis is a genus in need of serious revision.

More to come.

Randall Kohn

 

[Neil]

coenga,

WELCOME TO THE FORUM

Glad to have yet another hobbyist with a great deal of insight into a group of fish that there has not been a significant amount of work done and is changing as we speak. Increased collection of this species will probably provide more needed info, as well as interesting new species. Oliver Lucanus has a new form now that has no designation except, P.t. sp."purple" or P.t. sp."Badi River".
I am awaiting the info that Randall gets as well. Great info here already!
Neil

 

[tjudy]

VERY cool topic. More evolution.. OOO RAHHH!!! Here I go!

Pv taeniatus color is unstable in term of generations. "Kienke" F2 can be of "lobe" colormorphs.

The effect of specific limiting factors in a natural ecosystem can have some very profound efffects on phenotypic dominance in a population. The prevalance of a specific phenotype can change as quickly as the the limiting factors do. Some of the best work in this area has been done by Dr. Endler (of guppy fame) on Peocilia (spelling :?: ) species in wild and 'semi' wild populations. The natural genetic variability in wild populations is huge. It is no surprise to me that you are seeing a different phenotypic prevelance in captive bred lines by the F2 generation.. the selective pressures are entirely different.

Apparently, there is some mechanism in nature that enables syntopic (sharing the same habitat) taeniatus morphs to identify one another and to breed with their own kind. I believe this may go to "natural selection" in the Darwinian sense.

Reproductive barriers exist in three different forms: physical, geographic and behavioral. The concept of adaptive radiation in evolution is based upon the establishment, and maintenance, of these barriers between breeding populationa. A geographic barrier is obvious: the two populations cannot get into contact with each other. Physical barriers are associated with anatomy and physiology: such as species A having 50 chromosomes and B having 48, or A being a livebearer and B being an egg layer. The behaviorial barriers are the more difficult to define. When two closely related species are syntopic, the reproductive barrier is most likely behavioral. Behavioral barriers are also the easiest to overcome. The difference in the wild might literally be as simple as species A prefers flowing water while B prefers still water. That simple behavioral difference is enough to generate speciation.

 

[Randall]

Pv. taen. color morphs

Dear Colin,

Leave it to Ted to enlighten us, as he does so well, with an added dimension where breeding and speciation are concerned.

In an attempt to address your questions more directly, Dr. Loiselle seems to think that the three or more taeniatus morph groups, taeniatus, callipterus and kribensis, constitute a species complex of three or more differing species. When I showed him a photo of the "new" Pv. taeniatus "Ndonga," and told him that this morph was syntopic with a Pv. pulcher form from the same Cameroonian location, he commented that in Nigeria, Pv. pulcher is also syntopic with Pv. taeniatus "taeniatus" and that this came as no surprise. According to Loiselle, the taen. "Ndonga" morph falls under callipterus.

As for hobbyists identifing taeniatus aquarium strains, this can be quite difficult. Dr. Loiselle explains that hobbyists treat their taeniatus color morphs like killie fish: we tend to keep fish from the same populations separate from those from other populations. From a hobbyist's perspective, when two different morphs are interbred in captivity, we no longer have a pure morph. I'd advise against such a practice.

Because of identification problems, I tend to keep wild fish whose collection site is known and keep them separate from other morphs. That way, I'm assured of what I have and what I'm breeding. All I can recommend you do to identify tank raised specimens is to get as much information about the fish as you can concerning what country the original wild fish were from and where they were collected. Also, please note that in some morphs the males can look quite similar, but the females are quite distinctive. Compare, if you will, Pv. taen. "Wouri" females to "Moliwe" females. There is quite a difference.

I hope this information helps.

Good luck!

Randall Kohn