A rare, island-endemic damselfly described by Yasushi Asahina in 1952, belonging to a genus named after the Bonin (Ogasawara) Islands. Originally called Boninagrion ezoin.
From the IUCN Redlist (https://www.iucnredlist.org/species/2875/122058507):
This damselfly is endemic to the Ogasawara Islands, Japan. It is now extinct from Chichi-jima, Haha-jima, and Mukou-jima. Its current its distribution is limited to four islands: Muko-jima, Ototojima, Anijima, and Meijima. Its population has decreased due to recurring droughts, invasive species (a predatory reptile and invasive plants), and the remaining population is currently heavily reliant on conservation efforts to provide artificial ponds to replace habitat that has now been lost. The species is assessed as Endangered due to its restricted range (extent of occurrence of 258 km², and area of occupancy of 32 km²), occurrence in only four locations, and continuing decline in habitat and population size.