Okay, here's the text explaining the bold claim in the title!
February 2017: On my visits in July 2016 and February 2017 there were three cages tucked away very far behind a few other bird cages in the off-show area, two of which labelled "1,0 Goodman's" and "0,1 Goodman's" respectively (thus referring to Microcebus lehilahytsara), and the other was labelled "1,1 Maki trpasličí "červený."
"Maki trpasličí" is the common czech name for gray mouse lemur (but literally translates to "midget lemur"), and "Maki červený" is the common name for red mouse lemur.
The fact that the "červený" (which literally translates into red) was written between quotation marks made me doubt whether they actually have M.rufus or just (very small, as they were smaller than the M.lelilahytsara right beside them) M.murinus with a slightly more reddish coloration. The keepers present were no real help, as "really small monkeys" was the only thing they knew them by.
What made me wonder the most is that in July 2016, after seeing a lemur in that cage, I added M.rufus on Zootierliste, but quite some time later it suddenly wasn't listed anymore, not in former nor current listings, with no mention of it being taken down on the notice board.
So the options I thought about in February were:
1) They are M.rufus and the zoo wants to keep it a secret that they have them (though I wouldn't know why).
2) They are M.rufus and some misinformed other person removed them from Zootierliste.
3) They're just M.murinus with a slightly more reddish coat than usual and labelled as such (thus "červený" with the quotation marks).
4) They're just incorrectly labelled M.murinus or M.lehilahytsara.
Now: The Plzen Annual Report for 2017 was released today, and in it they mentioned 2,2,0 of their Grey mouse lemurs (Microcebus murinus) turned out to belong to a different, recently described species, Ganzhorn's mouse lemur (Microcebus ganzhorni). This potentially fixes a lot of the problems in the explanation above.
M.rufus I don't think can be an option, because of the fact that the species wasn't in the annual report for either 2016 or 2017. The (silent) removal from zootierliste probably reflects this, by somebody noticing it was mentioned on zootierliste and not on the annual report, and correcting zootierliste as such.
The size difference I think is the main clue; the two animals in the picture were notably smaller than the M.lelilahytsara right beside them. However, it is mentioned in many places that M.murinus is in fact the largest species of mouse lemur, so that doesn't make a lot of sense. I haven't had the time to fully read into the articles about M.ganzhorni, but since this was one of the more "cryptic" splits I assume size differences between M.ganzhorni and the rest of the very similar species will be minimal, and this species will thus generally be smaller than the biggest species, M.murinus (and potentially smaller than M.lelilahytsara).
The label "červený" also makes a lot more sense now, in that Plzen hypothetically noticed these were different, wrote down they were more "red" than the other, "normal" M.murinus they had, and then recently did more research on these "red" ones to see what species they actually belonged to.
It's hard to judge from this picture alone that these might be one species or the other (other meaning either M.murinus or M.lelilahytsara), and of course animals are often mislabelled in zoos (certainly in off-show areas I assume those are not the biggest of concerns), but the combination of the recent research, the note that these are more "red" than the others, and the fact that these were smaller than the M.lelilahytsara next doors made me draw the conclusion that these might be the M.ganzhorni mentioned in the annual report.
don't suppose you got any carnivore photographs whilst in Madagascar which could fill gaps in that thread?
