Kawahara, Akito Y.Toussaint, Emmanuel F.A.2018-07-012018-07-012018-07-01Proceedings of the Hawaiian Entomological Society (2018) 50:25–34.0073-134Xhttp://hdl.handle.net/10125/56591The Marquesan snout butterfly (Libythea collenettei) also known as “Papillon à museau des Marquises,” is the only endemic butterfly from the Mar- quesas Islands, French Polynesia. The butterfly is known from just five historic records. We report results from an intensive two–week survey in 2018. Our survey took place on the two islands where historic collection records exist (Nuku Hiva and Ua Pou), plus Hiva Oa and Tahiti, where the species has been thought to exist. Despite visiting multiple localities including sites where the species was previously observed, we were unsuccessful at detecting this species. The larval host plant, Celtis pacifica (Cannabaceae), can still be found on the Marquesas, indicating that the butterfly might still exist in the archipelago. Because the phenology of this species is unknown, future surveys should be conducted on the same islands but during different seasons. Given the very restricted geographic range of this species and threats to its habitat, we suggest that it be listed as endangered on the IUCN Red List.en-USFrench PolynesiaDanaus plexippusHypolimnas bolina otaheitaeIUCN Red ListArticle