Melanistic population of Z.longissimus in Cres

[Ruggero M.]

I already put my attentions to this 3D: viewtopic.php?f=13&t=881

Having observed a black colubrid 170 cm long in Cres does not mean it was a H.viridiflavus.

We have recently found on a total of 6 specimens of Z.longissimus, 5 blackish/aberrant specimens.
Some of them were almost totally dark grey/black on dorsum and belly: other appeared to have some spots of different colours (like "calico" variations). For instance, in the first big male we have found, the black belly had some yellow spots and was almost white towards the throath region. The head had many different colors and spots, as you can see in the following pictures.

Other specimens were almost totally blackish, in particular the smaller male (maybe 120-130 cm long).

We have not measured the specimens, but two big males were probably (in my opinion) around or even over 150 cm. The other rather big male was around 130-140 cm, and the smaller male around 120-130 cm. The female was a subadult specimen, and was probably around 70 cm.

We found also a "normal colored" brownish male, with slightly keeled dorsal scales, probably around 110 cm or slightly more.

I want to thank here my friend Carmelo Batti (who found most of the specimens photographed) and my german friends Achim and Rica Kempter who were kindly herping with us.

Other species of snakes found on the island during a two weeks period were:
H.gemonensis
Malpolon insignitus
Z.situla
E.quatuorlineata
Natrix natrix
C.austriaca

Male in situ: freezed position "en accordeon"

Details of head coloration of the male seen "en accordeon"

Other details

[Ruggero M.]

Another very long and big male (note the black belly)

[Ruggero M.]

A rather big male

Small subadult female

Another beautiful nearly totally black male

[Ruggero M.]

And now the only "normal colored" specimen

Male in situ

Detail for the slightly keeled dorsal scales I have observed

[Ruggero M.]

Just wanted to add a picture of the big male, which could be considered almost a "calico" specimen.

"Calico" male

And this is another picture of the small melanistic female

Melanistic subadult female

[Andre Schmid]

Very cool variants of the asculap snake !

[Ruggero M.]

Very cool variants of the asculap snake !

Thanks: I actually prefer yellow and lineated variants, but those animals were really pretty ones. Like big black "obsoleta" or maybe even like black small king cobras!

The distribution of Z.longissimus in Cres is a mystery, because it seems to be limited and restricted in the north of the island. And the reason for that is clear if you will visit the island: the northern part has a very typical habitat and clima for the aesculapian snakes, well separeted from the rest of the island by a narrow, steep and stony piece of earth, which for sure cannot be colonized by the aesculapian snakes.

But this report, from the outmost southern part of Cres http://en.balcanica.info/2-8672 is something really strange, which complicates our facts not slightly!

Any opinion about this?

[Mario Schweiger]

like on the neighbor island Krk.
Mostly in the forested areas, but sometimes "on the moon" in the south on the plateaus.
Also on Krk there are silver grey and black specimens.

Mario

[Ruggero M.]

like on the neighbor island Krk.
Mostly in the forested areas, but sometimes "on the moon" in the south on the plateaus.
Also on Krk there are silver grey and black specimens.

Mario

Thanks, Mario.

But Krk is large and rather uniform: Cres is narrow and very long. The strange fact is that on Cres nobody (as far as I know) has ever found aesculapian snakes in the middle of the Island of Cres: only in the north.

So it's very unusual another isolated finding in the extreme South of the Island (Punta Kriza): why an isolated population (?) in the South of the island? And, if so, in which type of habitat?

[Jeroen Speybroeck]

Also on Krk there are silver grey and black specimens.

Imho (and guess), these can be found throughout SE Europe. I have seen some near Mikri Prespa at least.