Endemic grasshoppers from the Mascarene Islands: a critically endangered island fauna

Abstract

Threats to the endemic grasshopper fauna of the Mascarene Islands (Mauritius, Rodrigues, and La Reunion), in the South Western Indian ocean are examined. Most endemic species were previously only known from very old type specimens lacking locality data. All were found again, and their precise distribution and habitat are given for the first time. The species Pyrgacris relictus Descamps, 1968, only known from the holotype and believed to be extinct, is rediscovered in a 0.4 km2 locality, but is under serious threat as its only habitat has been strongly modified during the past months. All Mascarene endemic grasshoppers are critically endangered. The total area of occupancy per species ranges between a few hectares and 5 km2, most species occurring in five or less locations. Mascarene grasshoppers rank among the most threatened Caelifera of known status in the world. However, most of their localities are included in a protected area, leaving hope to preserve these species, providing suitable conservation schemes are conducted.