Kingdom: Plantae
Division: Pteridophyta
Class: Pteridopsida
Order: Polypodiales
Family: Aspleniaceae
Genus: Asplenium 
Species: Asplenium
Scientific name:: Asplenium oblongifolium,
Common name: Shining Spleenwort, Paretao, Huruhuru, Paranako

Asplenium oblongifolium is a relatively small fern.  It has glossy dark green fronds which can reach about a 1.5 m in length when growing in optimum conditions in open but shaded parts of the forest. In some environments, it can be a dominant and quite conspicuous plant in the forest understory. It is endemic to New Zealand and the Kermadec Islands. It can be found growing on the ground and also in trees.

[1]   

A new frond.
[2]

The top surface of an adult frond
[3]

The undersurface of a frond
[4]

The sori on the underside of a fertile frond. The pinnae are in a herringbone configuration and they do not reach the margins.
  

Photos below are of juveniles.
[5]

[6]

Thanks to Wikipedia for text and information:

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