Re: Polygamic A. pertensis !!?

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

Fredrik,

Pertensis-group species are usually monogamous, like you say. A. pertensis
comes mainly from the Rio Negro where food is at a premium and fry are a good
source of food for many fish. This may encourage monogamy in the wild. In an
aquarium where there is more food and fewer predators, your male is taking
advantage of a good situation, I guess. Apistos seem to be good at adapting
to conditions.

A. pertensis is a fairly easy species to identify. The main problem most
people have with this species is the variability in the number of rows of
spots on the tail fin. The holotype shows a fish with only 5 or 6 rows. There
are photos of fish with 10 or more rows. This has confused hobbyists in the
past. Are these different species? Probably not. It appears that the number
of spot rows increase with the size of the fish to some extent. The male A.
pertensis in Linke & Staeck matches the holotype quite closely. So do most of
the photos listed as "A. pertensis" in the Aqualog book (p.55). The form
labeled "A. cf. pertensis" on the same page appears to be a different form
(species?). It is more elongate, with longer extensions on the dorsal, anal,
and ventral fins. The caudal fin appears to be longer, too. Could these only
be extremely old aquarium specimens of A. pertensis? I'm not sure.

Mike Wise

Fredrik Ljungberg wrote:

> Perhaps not the weird behaviour dept but still a bit remarkable.
> I have a trio of A. pertensis in a 150 litre-tank with some
> tetras and a couple of A. paucisquamis. My pertensis has always
> been monogamic even if I had more than a pair in a tank but
> this trio isn't, or the male isn't. He spawned both females
> within a week and is now helping both of them to protect their
> fry from the tetras. Really nice to watch and I guess he takes
> the chance when he can...
>
> Has anyone seen this in what is generally accepted as monogamic
> species?
>
> There is some confusion regarding A. pertensis and I am not sure
> that these are the true form even if they're very close. Does anyone
> (Mike?) know where/if there is a photo of the real A. pertensis in
> any book or online?
>
> Regards,
> Fredrik L.
>
> --
> Fredrik.Ljungberg@saab.se
> Flutter and Loads Department,  Saab Ab
> voice +46 13 18 54 60, fax +46 13 18 33 63
>
> -------------------------------------------------------------------------
> This is the apistogramma mailing list, apisto@listbox.com.
> For instructions on how to subscribe or unsubscribe or get help,
> email apisto-request@listbox.com.
> Search http://www.digital.com for "Apistogramma Mailing List Archives"!



-------------------------------------------------------------------------
This is the apistogramma mailing list, apisto@listbox.com.
For instructions on how to subscribe or unsubscribe or get help,
email apisto-request@listbox.com.
Search http://www.digital.com for "Apistogramma Mailing List Archives"!