Marine Captain
From Starbase 900 Wiki
In the Starfleet Marine Corps, Marine Captain is a company grade officer rank, with the pay grade of O-3. It ranks above First Lieutenant and below Major. A Marine Captain generally commands company-sized units and when given such a command, they bear the title company commander. Captains also instruct at service schools and combat training centers and are often staff officers at the battalion level. Marine Captains also serve as officer selection officers, commanding recruiting stations for commissioned officers.
It is equivalent to the rank of Lieutenant in the fleet rank system. The insignia for the rank consists of two vertical silver bars.