The Nita Maria is the smallest of Orlumbus' three ship classes. Its sails are arranged the same as the Santa Maria, with a black sail with the Jolly Roger in front, two sails in the middle, the top of which contains its name, and a sail in the back.
The ship, like its two counterparts, is based on the Santa Maria, the main ship of Orlumbus' namesake Christopher Columbus on his first voyage. "Ni," "San," and "Yon" mean two, three, and four respectively, indicating how the Nita Maria is the lowest in the order.
The names of these ships were revealed in SBS Volume 81. Following this, they were explicitly named in their debut in the anime.