This Vulcan crew member was in the astrometricslab aboard the Vahklas shortly after T'Pol went aboard the vessel and not long after the craft entered the Arachnid Nebula. He was initially at a computer display but, as Tolaris spoke to T'Pol about how he himself found the nebula beautiful, the other Vulcan male walked past T'Pol and out the room. (ENT: "Fusion")
Whether there were any female Vulcans serving full-time aboard the Vahklas is unknown. While working on repairing the Vulcan craft, Kov appeared to take particular note of the fact that there were many women aboard Enterprise. It therefore seems likely that there were either less, or no, females serving on the Vahklas. Yet, Kov admitting to CommanderTucker that the Vulcan crew was experimenting with methods of accelerating the Vulcan mating cycle would seem to indicate that there were women on board.