[2] The specific name xanthostomus is derived from the Greek words xanthos (=yellow) and stoma (=mouth) and refers to the characteristic yellow stripe along its mouth.

It is distinguished from congeneric species based on differences in size; having white and/or yellow spots on its forearms, mouth, belly and cloaca; the pattern and arrangement of warts; and the presence and number of corneous spines.

The dorsum is dark brown to black with a large yellow and white strip along the maxilla, extending up to the lower half of loreal region.

Specimens have been observed in terrestrial bromeliads, on bamboo, and on the ground (a pair in amplexus).

[5] Bornschein and colleagues suggested that it might qualify as "endangered" in view of its small range and disturbances to its habitat, including deforestation and fires.