A New Subfossil Night Heron and a New Genus for the Extinct Rail from Ascension Island, Central Tropical Atlantic Ocean

Ascension (Figs. 1, 2) is a recent volcanic island some 10 km in diameter lying at 07°57'S 14°22'W in the central tropical Atlantic Ocean 350 nautical miles south of the Equator. When discovered in 1501 it had a poor flora and terrestrial fauna, but many breeding seabirds presumably feeding along the equatorial current system (Bourne & Simmons 2001). The birds' destruction may have begun when Black Rats Rattus rattus escaped when William Dampier's ship the Roebuck was wrecked in 1701 (Osbeck 1771; Ashmole & Ashmole 2000). It was accelerated by Cats Felis catus introduced to control the rats when the island was settled in 1815 (Packer 1968; Ashmole et al. 1994). The BOU Centenary Expedition to Ascension of 1957-59 (Stonehouse 1960; Moreau 1962-63) found that the seabirds were by then mainly confined to outlying stacks and cliffs, apart from a vast colony or 'fair' of Wideawakes or Sooty Terns Sterna fuscata in the south of the main island. Ashmole (1963) found guano and bird bones still widespread, however, including two bones of an extinct flightless rail seen alive by Peter Mundy in 1656 (Temple & Anstey 1936). In 1970-71 Olson (1973, 1977) found more bones, including some of the rail, which he named Atlantisia elpenor, and a small night heron Nycticorax sp. During recent visits Simmons, John Hughes, the Ashmoles and John Walmsley have