Pterois miles, the devil firefish or common lionfish, is a species of ray-finned fish native to the western Indo-Pacific region. It is frequently confused with its close relative, the red lionfish . The scientific name is from Greek pteron, meaning “wing”, and Latin miles, meaning “soldier”.
Pterois miles was first formally described as Scorpaena miles in 1828 by the British naturalist John Whitchurch Bennett, with the type locality given as the south coast of Sri Lanka. A molecular study of this species, the red lionfish, the luna lionfish and Russell’s lionfish found that the common lionfishes in the western Indian Ocean formed a lineage, that a second lineage consisted of both the luna lionfish and Russell’s lionfish, suggesting these two taxa are conspecific, while the ref firefish formed a third lineage which appeared to have genetic contributions from the other two lineages. This suggests that the red lionfish arose from hybrids between P. miles and P. russelii sensu lato. The specific name miles is Latin for “soldier”; Bennett did not explain this, but it may be that the red colour reminded him of the red tunics worn by British soldiers in the 19th century.
The common lionfish grows up to 35 cm in length. The dorsal fin has 13 long, strong spines and 9-11 soft rays, and the anal fin has three long spines and six or seven soft rays. The dorsal fin appears feathery and the pectoral fins are wing-like with separate broad, smooth rays. These fish vary in colour from reddish to tan or grey and have numerous thin, dark, vertical bars on their heads and bodies. Its head is less angular than that of P. volitans.