042 was a Federation worker bee that was in service with Starfleet in the mid-23rd century, attached to the Federation starship Discovery. (DIS: "Despite Yourself")
Worker bee 042 was among those making external repairs to Discovery after returning to space from The Colony in 3189. (DIS: "People of Earth")
During the showing of Sherlock Jr. to the crew in the shuttlebay, worker bee 042 was parked near the aft wall of the bay. (DIS: "Forget Me Not")
Before and during the diplomatic mission to Ni'Var, worker bee 042 was moving cargo about in the ship. (DIS: "Unification III")
The numbers 042 were also digitally painted onto the side of a worker bee in service to the USS Shenzhou in "The Vulcan Hello", though lit by such a harsh light that the numbers were obscured. ("Creating Space", DIS Season 1 DVD & Blu-ray special features)