It is endemic to Papua New Guinea where it occurs in the central mountainous region between Chimbu and Morobe Provinces.

[1][3] The specific name parkeri presumably honours Hampton Wildman Parker, an English zoologist and herpetologist[4] to whose perusal Arthur Loveridge sent the holotype.

[3] In the Kalam language of Papua New Guinea, mature C. parkeri are known as kabanm, while immature specimens are called lk [lɨk].

Most specimens do not have distinct dorsal patterns but have a dark brown dorsum that grades rather abruptly into the pale reddish tan flanks.

[7] Cophixalus parkeri inhabits montane rainforest and forest edges at elevations of 2,200–2,650 m (7,220–8,690 ft) above sea level.