The Rhitorri were an insectoid humanoid species native to the planet Rhitorrus. They had a black, chitinous exoskeleton covered in feathery fur. Their lifespans were shorter compared to Humans, with twenty years covering six generations, and they were resistant to radiation. (STA - Tales from the Captain's Table short story: "Darkness")
In the early 24th century, the society of Rhitorrus was oppressive. A peaceful sect escaped from the planet but were pursued by a Rhitorri warship for a year. The warship attacked the dissidents' but were dissuaded from harming them further by Captain Jean-Luc Picard of the Federation starship USS Stargazer. The warship retreated, and Picard hailed the dissidents. Their systems and logs only preserved little data, including the ship's dedication plaque. They copied the text. "To bring light into the darkness..."
In 2355, the Skellig came across the colony and started attacking it. The shields defended the Rhitorri city. Three days later, five Skellig raiders attacked the Starfleet cargo shuttle Nadir when it was making an emergency landing. Captain Picard, who had been aboard the shuttle, joined forces with the Rhitorri after they retrieved him.
When the city's shields fell, the Rhitorri expelled radioactive vapor from their towers, which prevented the large Skellig ships from beaming down troops. The Skellig wanted to capture the radiation-resistant Rhitorri to use as slave labor for radioactive environments. Skellig troops landed with small craft and attacked the Rhitorri in the underground. Picard fought them back before he lost consciousness due to succumbing to the radiation.
When the USS Wyoming arrived to respond to Nadir's distress call, David Capshaw led an away team helping repel the raiders. The Wyoming fought the Skellig ships, and the Skellig retreated. Picard was recovered and cured. Capshaw told him the ship would remain at the planet to protect the Rhitorri from further Skellig raids.
The Rhitorri were grateful for Picard's help, believing he had single-handedly held off the troops on the ground. They did not recognize him for the captain who saved them two decades earlier, however. (STA - Tales from the Captain's Table short story: "Darkness")