What is "tooth-billed pigeon"

The tooth-billed pigeon (Didunculus strigirostris), also known as the manumea, is a large pigeon found only in Samoa. It is the only living species of genus Didunculus. A related extinct species, the Tongan tooth-billed pigeon (Didunculus placopedetes), is only known from subfossil remains in several archeological sites in Tonga. The tooth-billed pigeon is the national bird of Samoa and featured on the 20 tālā bills and the 50 sene pieces of the 2008/2011 series.