Unusual dog found in the woods in Croatia?

A friend found her in the woods near Rijeka, Croatia in february 2016. The first picture is from the first week she’s been with me (vet said she was about 3-4 months old). The other pictures are something like a month old.
She is about a year old, weighs 18 kg. Has a ridge from her head to her tail when she is frightened or excited, although when we play the ridge isn’t visible except a small ring in the middle of the tail. She has a black tail point (more visible when she was a pup). She has black pointy nails and webbed feet.
On the character part she is very, very fast, can jump very high. She is also very clean and elegant. Loves to sniff and if isn’t hungry she will hide it for later. She can be trusted off leash in midst of people (children dogs etc…) but not around cars because if she sees a squirrel, a mouse or a bird will try to catch it (she is very friendly towards cats tough).
She adores the sun and heat, tolerates rain and doesn’t like cold temperatures (begins to shiver if static around 10-15°C). She likes to fool around in shallow water but won’t go to the deep end by herself.

I found multiple breeds that are similar to her one way or another…from basenji, pharoh hound, phu quoc ridgebach to portuguese podengo but still i wonder:)

If anyone is interested i have more detailed pics.

Best regards

Luka