T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Elatostema rugosum (Parataniwha)

Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Rosales
Family: Urticaceae
Botanical name: Elatostema rugosum
Common name: Parataniwha, Native begonia, winkled elatostema, New Zealand Begonia,  Parataniwhaniwha.

Parataniwha is a member of the nettle family. It is a herbaceous ground cover plant and is one of our very few perennials. It grows up to at 1m tall in wet shaded areas such as damp shady streamsides and gullies. It can form large colonies and is often the dominant groundcover vegetation. It has large prominently veined bronze green leaves (8-25 cm long) with purple tonings. The distinctive rough leaves give rise to the taniwha part of the common name because of taniwha in Maori means shark. (After the sharks rough skin)
Parataniwhais is found naturally only in the North Island.

Photo below is of a patch of burnished purple-red Elatostemma rugosum  which must get just enough sun to turn the leaves this rich colour, whereas the patch in a lower photo is in complete shade and is green in colour.
Photographed at Burgess Park, New Plymouth. 

A young plant with small male flowers appearing on glomerules/

Young glomerules are fleshy pads of tissue, each containing a large number of developing flowers. Glomerules are 0.5-30 mm in diameter when matue. Flowers are unisexual and may be mixed in the same glomerule.

The hyaline ((Gr. hyaleos: transparent) male flowers are 1-3 mm in diameter and consist of four translucent tepals and stamens. The stalk (filament) of each stamen is curled tightly like a watch-spring in the bud and springs open when the anther is mature. 

A young leaf.

A leaf's upper blistered surface with raised and recessed areas and widely spaced hairs.  These hairs are multicellular, unbranched and taper from the base to the tip.

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/