Megophrys nasuta is larger than M. montana. If your frog is about 3.5 inches long it is a male Megophrys nasuta. They are more common in the hobby. They need to be kept at about 67-72F in a terrarium with LOTS of leaf cover, caves or other hides. Oak and magnolia leaves with cork bark curls work well. Plain cocoa fiber (Bed A Beast type substrate) seems to irritate them, so a deep drift of leaves on top works better. They don't bask, and bright light stresses them especially at first. A generous shallow water area with rainwater or treated tap water (if your tap water is chlorinated you'll need to treat it). The frog won't want to be visible at all except at night, so not a great display pet unfortunately. They will eat nightcrawlers, crix, medium roaches, superworms, and waxworms, but they don't usually roam around to hunt. The food has to walk right up to them before they lunge at it. The males call at night and it sounds like a VW bug car horn. You probably don't want him in your bedroom! Depending on where you live, you may not be able to use wildcaught insects. There are places in the US where chytrid fungus occurs. Chytrid will probably kill him, so use cultivated feeder insects. There are some other people who keep Megophrys on other forums including pollywog.uk, caudata.org, and dendroboard. If you have other questions I may be able to help.
Anyone else on this forum working with Megophrys? I've had a LTC male for years, and finally have a group of 4.2 (possibly 3.3 but I'm not sure about one of them).