Limnonectes megastomias is a species of frogs with fangs that was discovered in Thailand in 2008.

[2] Limnonectes megastomias has been recorded from these locations in eastern Thailand (McLeod, 2008).

Males have nuptial pads, consisting of tiny spines on the medial surface of Finger I and the dorsomedial surface of Finger II, above the fringe on the preaxial side.

The upper lip is swollen and flares out, extending as far as the post-rictal tubercle.

Eyes have a diameter 15% of the head length, and the upper eyelid width is 63% of the interorbital distance.