Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia
clade Euthyneura
clade Panpulmonata
clade Eupulmonata
clade Stylommatophora
clade Elasmognatha
Superfamily: Athoracophoroidea
Family: Athoracophoridae
Genus: Pseudaneitea
Species: Unknown

This is undescribed alpine native air-breathing land slug is in the Pseudaneitea genus, in the family of terrestrial gastropod molluscs called Athoracophoridae, the leaf-veined slugs.
It was photographed by Brando Yelavich of Wildboy adventures at 1,522m near Lake Chalice which is located in Mount Richmond Forest Park in the Marlborough region.

Leaf veined alpine slug.jpg

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/