Species

Ixerba brexioides

Etymology

Ixerba: an anagram of brexia
brexioides: like a Brexia, a South African shrub

Common Name(s)

Tawari, whakou (flowers)

Threat Status

Non Threatened

Status 2004

Non Threatened

Authority

Ixerba brexioides A.Cunn.

Family

Strasburgiaceae

Flora Category

Vascular - Native

Synonyms

None

Distribution

Until recently (2009) Ixerba was briefly placed within its own monogeneric family the Ixerbaceae. This was New Zealands only endemic vascular plant family. In 2009 the APG merged the Ixerbaceae with the New Caledonian Strasburgiaceae. Ixerba is confined to the northern North Island from about Waitomo, Paeroa Range and Te Urewera northwards to the ranges just south of Kaitaia.

Habitat

An associate of kauri (Agathis australis (D.Don) Lindl.) forest and montane cloud forest. Prefers shaded or sheltered sites, often near streams and in permanently damp ground. Can be locally abundant in some areas but otherwise it is rather sporadic in its occurrences,

Features

Small tree up to 10 m tall with spreading crown. Trunk 0.2-0.4 m diam., bark dark brown to grey-brown. Branchlets, leaves and inflorescences clade in fine pubescence when young. Petioles, stout, fleshy, 20 mm long. Leaves yellow-green to dark-green above, paler beneath, somewhat fleshy, distinctly leathery, 60-160 x 10-40 mm, lanceolate to elliptic or oblanceolate, apex acute to subacute, margins bluntly and coarsely serrated. Apex of each serration surmounted with a small gland. Juvenile leaves often reddish, linear-lanceolate. Inflorescence a terminal subumbellate 5-10-flowered panicle. Flowers 25-35 mm diam, furnished with plenty of nectar. Sepals broad-ovate, downy, 5-6 mm long; petals white, obovate-spathulate, clawed, 15-20 mm long, inserted below a 5-lobed disc; stamens 5 exserted, alternating with disc lobes; style twisted, 5-grooved. Capsule leathery, broadly ovoid, 5-celled, seeds orange, 5 mm long, very glossy.

Similar Taxa

A very distinctive tree easily recognised by the leathery, somewhat fleshy, lanceolate leaves, whose serrations are glandular-tipped, large, showy, white flowers, and distinctive capsules which split to reveal rather large glossy black seeds.

Flowering

(September-) October-November (-December)

Main Flower Colour

White

Fruiting

November - January (-March)

Propagation Technique

Difficult to grow. It has been suggested that the species is mycorrhizal, and there is some evidence that if planted in association with Griselinia littoralis, Ixerba grows very easily.

Threats

Not Threatened

Chromosome No.

2n = 50

Endemic Taxon

Yes

Endemic Genus

Yes

Endemic Family

Yes

This page last updated on 16 Jan 2013