Bos frontalis and Bos gaurus (Artiodactyla: Bovidae)

Bos frontalis Lambert, 1804 and Bos gaurus Hamilton-Smith, 1827 are the domestic and wild forms, respectively, of the bovid commonly called the gaur. It is the world's largest cattle species. Bos gaurus is endemic to south and southeastern Asia, and today, the majority of its population occurs in India. It is sexually dimorphic, with adult males having a distinctive dorsal ridge and often a dewlap. Although B. gaurus consumes numerous browse species, it is primarily a grazer. Except for older males, all other B. gaurus are nearly always found in herds. It is classified as a Vulnerable species, and in 2011–2012, the first reintroductions of B. gaurus occurred in central India.