Dereth

From Memory Alpha, the free Star Trek reference

Dereth was a Vidiian artisan suffering from the phage. His duty as a Honatta was to locate and harvest new organs for Motura. In 2371, he harvested Neelix's lungs and implanted them into Motura.

After Captain Janeway decided to spare Motura's life despite their actions, Motura convinced Dereth to help them. He later used Vidiian medical technology to transplant one of Kes' lungs into Neelix, saving the Talaxian's life. (VOY: "Phage")

[edit] Background

Dereth was played by Cully Fredricksen, who later played the Vulcan captain who made first contact with Zefram Cochrane in Star Trek: First Contact.