What is a parasite ship? Is it shuttles? Or something more complicated than that?
One answer would be, anything you want.
In general a parasite ship is any ship that can fit in the "internal ship hanger" based on tonnage.
In practice, v2.5 anyway, the parasite is a specially built small warship (1000 tons or less). There a some special tech available (such as gunboat engine) to help build functional ships this small.
Think of it being a morph of the Starfire gunboats and SFB Andromada satellite ships.
