Different varieties of Plain-pouched Hornbills. On the left, a plaque of a male (fig.) and female Plain-pouched Hornbill (fig.) at the Jurong Bird Park in Singapore. They are however different from the ones in the photo below.

On the right, a depiction of a 1996 Thai postal stamp, i.e. one from a set of four (fig.), featuring a variety similar in appearance to the Wreathed Hornbill (fig.), with the male having a shaggy, brown, mane-like crown and large yellow gular pouch, and the female with a large blue gular pouch.