Chayote squash is an excellent source of dietary fiber. Chayote squash, or Sechium edule, is the Mexican term for the vegetable that some Americans call a vegetable pear. Christophine is another name for this small, green squash.alories and Macronutrients. The serving size for chayote squash is 1 cup of boiled squash. Each cup weighs 160 grams, or 6 ounces, and contains 38 calories. The squash is so low in calories because of its high water content.