So cool! I saw this species in Khao Yai National Park last month. Unfortunately we didn't had the best guide that day, and he decided it wasn't work stopping the car for.
That is a shame, as they are a cool species! In Khao Yai, the guides seemed to think every tourist is just there for the elephants and monkeys. Still glad I hired a car and drove around myself, so I could stop whenever I want. Definitely worth the hassle of navigating the Thai roads.