Halosaurus johnsonianus, also called the Sahara halosaur, is a deep-sea fish in the family Halosauridae. It is found in the eastern Atlantic Ocean from southern Spain and Portugal to Mauritania, including the Azores and Canary Islands. It is a benthopelagic species living on the continental slope in depths from . It grows to total length.
Halosaurus johnsonianus is not a fishery species, and no significant threats to it are known.