Pactola kuscheli sp nov (Coleoptera: Curculionidae), a potential cause for the decline of the threatened New Caledonian conifer, Agathis montana de Laubenfels, 1969 (Araucariaceae)

Agathis montana is a conifer endemic to New Caledonia and one of the most threatened (Critically Endangered) plant species of this area. The exact causes of its decline are still unknown. The authors describe the characteristics of A. montana, the history and methodology of population monitoring, and possible factors causing the decline and habitat degradation. In 2014, some twigs showing symptoms suggesting attack by wood-boring insects were collected. From these, imagines of an unknown weevil species belonging to the genus Pactola Pascoe (Eugnomini) were reared. The new species is described as Pactola kuscheli Mazur sp. nov. Colour photographs of the dorsal habitus, line drawings of taxonomically relevant structures and a key to all New Caledonian species of Pactola are provided. The biology of P. kuscheli Mazur sp. nov. is described and its role as a key threatening process of A. montana is discussed.