I had an exotic fruit in central America...?

and I want to learn if it I can buy it somewhere. Unfortunately, the name seems impossible to spell. it is called (mar-ih-koo-ya, I can't spell the name). it is pink and green on the outside (I think, I know it is somewhat pink) the inside is a yellow pulp with green seeds about the size and shape of apple seeds. It is eaten like a gfruit, cut in half and eaten at breakfast. It is about the size of a hackey sack and it is very sour. Please help me find out what this fruit is called in English.