What is unique or rare about the VM Zodiac signs?

[MarcoP]

Hi Koen,
it seems you have already collected a good part of the most relevant stuff. Well done!

Here are a few comments:

Cancer

While double crayfish are possibly unique, double crabs do appear in other manuscripts.

As far as I know, double crabs appear in a single manuscript: You are not allowed to view links. Register or Login to view. (England, ca. 1325-1330, discussed by Olga Koseleff Gordon).

Leo
Maybe the bestiary lion you previously referred to is this one, discussed on the site of Stephen Bax?
You are not allowed to view links. Register or Login to view.
It appears in a ms pointed out by Darren Worley (Biblioteca Apostolica Vaticana, Pal. Lat. 291, Rabanus Maurus, South Germany, 1425).

Virgo
As already mentioned You are not allowed to view links. Register or Login to view., and discussed on You are not allowed to view links. Register or Login to view., Virgo holds a "tailed star" which seems quite unique. Of course, most illustrations of Virgo have something representing "Spica", but not in this form, as far as I remember. Even if this "Spica" turned out not to be totally unique, the tethered star is similar to those in Pisces and Scorpio. This systematic deviation from common images of the zodiac signs is worth mentioning, in my opinion.