Dirgo was a humanoid male – of a species possessing a heavy brow, and a slightly wrinkled nose with a slightly bifurcated nasal tip – who served as the captain of the mining shuttle Nenebek during the 2360s.
In 2367, he was sent to transport Captain Jean-Luc Picard to Pentarus V to arbitrate a miners' dispute. Wesley Crusher accompanied them on the mission.
His ship, which was in poor condition, crashed on Lambda Paz, a moon of Pentarus III. The moon was a desert, and his ship had no emergency food or water. They found shelter in a cave that contained a fountain of water, but were prevented from getting to it by a force field. Dirgo tried to shoot through it, but an energy sentry knocked him down and caused a rockslide, injuring Picard. Dirgo tried to use a phaser again, and he was enveloped in electrically-deposited selenium fibers by the energy sentry, killing him. (TNG: "Final Mission")
Dirgo was played by actor Nick Tate.
According to the script notes, "Dirgo is a tough-looking humanoid who is weathered and worn enough to suggest middle-age. Though his appearance is feral, he will emerge as an intelligent, if inflexible, being. Ultimately, he is self-serving; Dirgo looks out for Dirgo, because he's always had to." [1]
StarTrek.com called him a "Pentaran shuttle pilot". [2](X) It's unclear if "Pentaran" is the name of his species or just refers to him being associated with the Pentarus system mining operation, especially since there was no hint of a native population in the system.