Researchers have discovered a new species of tree frog on the slopes of a flat-topped mountain in a remote region of the Ecuadorean Andes, which is considered to be one of the richest areas for biodiversity in the world.According to a study published in the journal ZooKeys, the amphibian has dark brown skin dotted with orange flecks and features a large and unusual claw-like structure protruding from the base of its thumb, known as a prepollex.