According to the US Fish and Wildlife Service Species List (US Fish and Wildlife Service Species List 1999), there are 42 local populations of Diellia spp. in the Hawaiian Islands. Among them, 22 local populations represent D. falcata; the remaining 20 populations did not include D. mannii (rediscovered in 2002, cf. Aguraiuja and Wood 2003) and populations with taxonomically unclear status.