Pond creatures (f79v)

[MarcoP]

Hello Koen Gh,
thank you for pointing out these interesting images.
I think the only relevant pattern is the dot line on the bottom left figure: they were drawn in dark ink, while I see the others as accidental effects of paint “splashing”.

That line of dots is strongly suggestive of a salamander or newt, “stellio” (“starred”) in Latin.
Attached images from top to bottom:

[Voynich]
Bibliothèque Nationale de France, lat. 6838B, Folio 34v
Kongelige Bibliotek, Gl. kgl. S. 1633 4º, Folio 55v
Bibliothèque Nationale de France, lat. 14429, Folio 112r
Koninklijke Bibliotheek, KB, KA 16, Folio 126r
Michael Maier, Atalanta fugiens, 1618?

More images here:
You are not allowed to view links. Register or Login to view.
You are not allowed to view links. Register or Login to view.

PS: The Salamander is also related with water and in bestiaries it is sometimes represented entering a well (see image on the left):
You are not allowed to view links. Register or Login to view.
if it falls into a well, the strength of its poison kills those who drink the water. 
(the Aberdeen Bestiary, Aberdeen University Library, Univ Lib. MS 24, 12th-century, England )

PPS: see also You are not allowed to view links. Register or Login to view.:

• Several different animals on fol. 79v. These could be a fish, a salamander, a lion, and a lamb in the "Golden Fleece" posture.