Definition: A taxon is Extinct when there is no reasonable doubt that the last individual has died. A
taxon is presumed Extinct when exhaustive surveys in known and/or expected habitat,
at appropriate times (diurnal, seasonal, annual), throughout its historic range have failed
to record an individual. Surveys should be over a time frame appropriate to the taxon’s
life cycle and life form.
Definition: A sheet of saline water separated from the open sea by sand or shingle banks. The sheet of water between an offshore reef, especially of coral and mainland. The sheet of water within a ring or horseshoe shaped atoll.