I was leading a birdwatching tour in the mountains of Chiapas, Mexico, when I found this frog in a small stream along the edge of a rocky outcropping in the forest. This location is at an elevation of ca. 1235 meters. I was able to take a number of images of this animal. Dr. Jon Campbell, herpetologist at the University of Texas at Arlington, believes it is Plectrohyla matudai from examining several of my photos a few years ago, but he cautioned that a positive ID may not be possible from photos. One of the common names is Matuda's Spike-thumbed Frog in addition to the common name used in this document.
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