Re: P. taeniatus or subocellatus Matadi?

[Mike & Diane Wise <apistowise@bewellnet.com>]

Ken Laidlaw wrote:

> >
> > as someone pointed out, the "taeniatus" complex is probably not a single
> > species.
>
> I would have though all the appropriate tests would already
> have been done that proved that all the colour morphs were
> the same species.  What happens if they are crossed
> etc, scale counts etc.  What are the two Bolivian Ram
> species, I'm confused?

Ken,

Since I'm the one who made the statement here to Fredrik's question of Pv.
taeniatus color forms, I guess I should answer this.

Most of the following information came to me from Dr. Paul Loiselle. Paul played
a prominent role in describing many of the new genera and species that were once
members of the polyglot genus Pelmatochromis. Paul will tell you that the
taxonomy of the West African pelmatochromines is still unclear because of the
lack of specimens & adequate sampling of West African rivers.

You are correct in a taxonomic respect. In 1968, while splitting up the genus
Pelmatochromis into several genera, Thys examined Pelmatochromis callipterus,
kribensis, and taeniatus. He determined that these species had overlapping
meristic characters and should be considered one species -  Pelvicachromis
taeniatus (Boulenger, 1901), the oldest name in the group.

In a taxonomic sense, he is correct. Paul says that if you put any of these fish
in alcohol, they will lose their colors and all look the same. But a problem has
arisen. Studies of some Camaroonian rivers show that there is at least one
instance where two color forms of so-called Pv. taeniatus are found living
sympatrically together, but don't interbreed with each other. Since the
biologist's definition of a species is a group of populations that will
interbreed, we obviously have two very closely related biological species here. I
imagine, if more detailed biotope studies were carried out, we would find similar
occurrences elsewhere. How many different non-interbreeding populations are out
there is anyone's guess, but it is a valid reason for never crossing color forms.
And most likely they will cross in the aquarium if they aren't given a choice.

Those who were at Paul's talk, at last year's ACA convention, might remember how
he differentiated the species by color. I could do this right now, but I feel
it's better to leave things as they are. There's no sense in renaming the color
forms now, when in a few years it might be erected to species rank and given a
new name. Just more taxonomic confusion!

Mike Wise

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