A new miniature species of microhylid frog in the genus Cophixalus Boettger, 1892 (Asterophryinae) from Papua New Guinea

A new species of miniature (males < 13 mm SUL) eleutherognathine asterophryine microhylid frog is described from the mountains of Papua New Guinea. Cophixalus leptoglossa sp. nov. differs from all other New Guinean Asterophryinae in its unique combination of having a distinct cream stripe along the canthus, a dark brown hourglass mark on the dorsum, eight presacral vertebrae, no prepollex element and two prehallux elements, tips of toes 2–5 expanded, Musculus depressor mandibulae located entirely behind posterior margin of tympanum, and omosternum present. In its small size, reduced first finger and strap-like tongue the new species is morphologically most similar to the genus Paedophryne. However previously published genome-scale sequencing using Single Nucleotide Polymorphisms (SNPs) confirms that it is a deeply divergent lineage within the genus Cophixalus. The new species inhabits leaf litter on the forest floor where males call predominantly during the early morning and late afternoon. It is currently known only from the Lake Kutubu Wildlife Management Area and nearby forested ridges at the eastern edge of the Agogo Range in New Guinea’s central cordillera.