Revision and phylogenetic analysis of the Papuan weevil genus Thyestetha Pascoe (Coleoptera, Curculionidae, Cryptorhynchinae)

Thyestetha Pascoe, an apterous genus of Papuan Cryptorhynchinae is revised. It contains two previously described species, T. carbonaria Faust and T. nitida Pascoe, plus seven new species: T. discolor sp. n., T. emarginata sp. n., T. glabra sp. n., T. lubrica sp. n., T. oblita sp. n., T. puncticollis sp. n., and T. splendens sp. n., Lectotypes are designated for T. carbonaria, T. nitida, and Pantoxistus rubripennis Chevrolat which is a junior synonym of T. nitida (syn. n.). The genus and its species are described and the characters relevant for their identification are illustrated. A key to the species is provided. Phylogenetic analyses are performed, utilizing molecular and morphological approaches. A maximum likelihood tree including 5 Thyestetha species and 2 outgroups is presented, based on 3 mitochondrial and 4 nuclear markers. A maximum parsimony analysis of 19 morphological characters includes all described species. Thyestetha is presumably closely related to Telaugia Pascoe and Elichora Pascoe. The group is restricted to New Guinea and some smaller neighboring islands.