Quick facts about the engineer goby, a unique fish that likes to create tunnels in the sand! Engineer goby (convict blenny, convict goby, engineer blenny, Pholidichthys leucotaenia, convict fish). Engineer goby facts! The engineer goby or convict blenny is a marine fish that has an eel-shaped body. It inhabits coral reefs in the Indo-Pacific in areas such as the Philippines and the Solomon Islands. They are often seen along reef drop-ffs. Despite its name, this fish is neither a goby nor a blenn