The term 'Wrinkly Tangelo' is a combination of two different citrus fruits: the tangelo and the ugli. The ugli is a Jamaican citrus fruit that is a hybrid of a grapefruit, an orange, and a tangerine. It has a thick, wrinkled skin and a sweet-tart flavor. The tangelo is a hybrid of a tangerine and a pomelo, and it has a sweet-tart flavor as well. Together, these two fruits make up the Wrinkly Tangelo, which is a unique and flavorful citrus fruit.