Z'on's species

Z'on's species were a humanoid species with blue skin (at least around the neck area), and, at least some members, required a an electronic device to allow them to "speak".

In the 2290s, a member of the species, Z'on, was a lieutenant in Starfleet, and served as communications officer aboard the USS Enterprise (NCC-1701-B). (TOS novel: The Captain's Table).