Nyctibatrachus radcliffei was described in 2017 by the herpetologist Sonali Garg and her colleagues based on the holotype, an adult male specimen collected from the Thiashola estate in the Nilgiris district of Tamil Nadu, India in 2016.

The species is named after Major Richard Radcliffe, a British conservationist, to honour his contribution towards the conservation of wildlife in the Nilgiri Mountains.

[5] According to the 2017 study in which it was described, it is sister (most closely related) to a clade (group of organisms descending from a common ancestor) formed by N. acanthodermis, N. gavi, N. grandis, N. sylvaticus, and N. major.

[1] In adult males, the upperside of the body and the sides of head are reddish-brown with scattered blackish-brown spots, with dark brown upper eyelids.

[1] N. radcliffei is endemic to the Western Ghats of India, where it is known only from the Thiashola estate in the Nilgiri Mountains north of the Palakkad Gap, where the specimens used to describe the species were originally collected.

All known specimens of the frog have been collected from hill streams in a tea estate, hiding in crannies under rocks at elevations of around 1,920 m (6,300 ft).