Arndt's Choerophryne

Adult males measure 11–15 mm (0.43–0.59 in) in snout–urostyle length; females are unknown. The snout is long and pointed (7–9% of the body length). The eyes are relatively large. The tympanum is small. All fingers and toes expect the first ones bear discs. The dorsum is reddish, greyish, or brownish, while the ventrum is grey-brown, blackish, or brownish. Most specimens have an hour-glass marking on the dorsum, and many have a broad, light-coloured dorso-lateral stripe. The male advertisement call is a series of typically four (range 1–5) distinctly pulsed notes. Each note consists of 22 to 44 pulses, with dominant frequency at 5.1 kHz.

At the type locality, Choerophryne arndtorum inhabits primary and secondary rain forest at elevations of 500–700 m (1,600–2,300 ft) above sea level. It was found to be locally common, with 150 calling males found in a half hectare area. Males call from on or in leaf litter, sometimes higher from the ground (to 1.2 m) on plant stems. Development is direct (i.e., there is no free-living larval stage).