It is endemic to southwestern Chiapas, Mexico, where it is only known from the Cerro Tres Picos, the type locality.

The snout is elongate and have extremely large nostrils (to which the specific name megarhinus refers).

The alcohol-preserved specimens are dorsally dark brown with some darker and light mottling along the middle of the back and tail.

[2] The habitat of Dendrotriton megarhinus is cloud forest at an elevation of about 2,000 m (6,600 ft) above sea level.

There are no direct threats to this species but its small range renders it vulnerable to stochastic events.