Q: While at anchor during a recent trip to the Andaman Islands in the Indian Ocean, we caught several of these beautiful fish on cut bait. They have some characteristics of porgies, but I'm not sure they're in that family. What did we catch? What's its range and how large does the species get?

Rob Sherman
Pacific Palisades, California

A: What you caught is a Robinson's sea bream or blue-lined large-eye bream, Gymnocranius grandoculis. It's also known as a blue-lined emperor since it's a member of the emperor family Lethrinidae, a group of warm-water fishes related to sweetlips (Haemulidae) and snappers (Lutjanidae). This species occurs throughout the tropical Indo-Pacific except for the Persian Gulf, Gulf of Oman and Hawaiian Islands. Robinson's sea bream may grow to 30 inches long and weigh about 12 pounds. Bottom feeders, they frequent sandy areas near coral reefs and mainly prey upon crabs and mollusks. Juveniles are silver with strong, brown bars across the flanks. Adults are more uniformly silver with reddish/yellow tints to fin edges and thin, wavy, broken blue lines on the cheek, separating them from other species of the genus Gymnocranius. — Ben Diggles