Nylgaa or Nylgau: How To spell?

The word Nylgaa is misspelled against Nylgau, a noun meaning "A large Asiatic antelope (Boselaphus, / Portax, tragocamelus), found in Northern India. It has short horns, a black mane, and a bunch of long hair on the throat. The general color is grayish brown."