This plant has emerged in our garden. We have no idea what it is
HI that looks like an arum of some sort - definitely not a native species. It may not be this species exactly but you can see the similarities http://www.nzpcn.org.nz/flora_details.aspx?ID=3473. Fleshy fruits shown in your photo will be eaten and spread bybirds
Alocasia brisbanensis - it is toxic - see http://www.nzpcn.org.nz/flora_details.aspx?ID=2493
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