[Distribution of Simulium buissoni Roubaud, 1906 and S. sechani Craig & Fossati, 1995 (Diptera: Simuliidae) in Nuku-Hiva and Eiao (Marquesas Archipelago, French Polynesia)].

Nuku-Hiva and Eiao are the only islands of the Marquesas archipelago where blackflies bite humans. Knowledge of the geographic distribution of species is necessary to optimize control operations. Looking at frequency distributions of labral fan rays numbers from a large sample of larvae allowed redefinition of species. Simulium sechani Craig & Fossati, 1995, become the only species represented in Eiao. This species live in Nuku-Hiva too, but is limited to the external part of the main caldera. Presence of S. buissoni Roubaud, 1906, in all part of the island is confirmed, as is presence of S. hukaense Séchan, 1983 but in reduced number. Large samples of S. sechani extends its labral fan rays numbers. Stability of the described repartition over several decades is shown.