Ten new species of <i>Oreophryne</i> (Anura, Microhylidae) from Papua New Guinea.

Oreophryne presently represents the second-most-diverse genus of microhylid frogs, with 57 named species, most occurring on New Guinea and its satellite islands. Nonetheless, a diversity of species remains to be described. Using morphological, color-pattern, and advertisement-call data, I describe ten new species of Oreophryne from the Papuan Peninsula of New Guinea and adjacent islands, which together form the East Papuan Composite Terrane. All but two of these species can be placed into two species groups based on call type. I refer to these species groups as the O. anser group and the O. equus group, both being based on species described herein. Members of the O. anser group produce calls reminiscent of a goose honk, whereas members of the O. equus group produce calls reminiscent of a horse's whinny. Description of three new species in the O. anser group requires me to first rediagnose O. loriae, which has previously been interpreted as including the frogs named herein as O. anser sp. nov. The honk call type has not previously been reported within Oreophryne, and the whinny call may be novel as well, although it is possibly derived from other New Guinean species having calls consisting of a slower series of peeps. Based on their unique call types, I hypothesize that both species groups are monophyletic. If true, each would appear endemic to the East Papuan Composite Terrane. Only five additional species of Oreophryne are known from this region that do not belong to one or the other of these two species groups; hence, these newly identified species groups represent the majority of diversity in Oreophryne from the Papuan Peninsula and its satellite islands.