Species

Ileostylus micranthus

Etymology

Ileostylus: style folded like a small intestine
micranthus: small flower

Common Name(s)

green mistletoe, pirita

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened

Authority

Ileostylus micranthus (Hook.f.) Tiegh.

Family

Loranthaceae

Brief Description

Bushy yellowish-green shrub growing on other trees with clusters of tiny green flowers and orange fruit. Leaves fleshy, variable in shape, 30-80mm long, in pairs on stalks that arise from a flattened section of the squareish stem. Roots creeping along host plant’s stem.

Flora Category

Vascular - Native

NVS Species Code

ILEMIC

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Dicotyledonous Trees & Shrubs

Synonyms

Loranthus micranthus Hook.f.

Distribution

Indigenous. North, South and Stewart Islands, also on Norfolk Island.

Habitat

Mainly a coastal and lowland species which rarely extends into upper montane forest. Prefers shrubland and secondary regrowth. This species shows some regional host specificity but nevertheless has been recorded from a wide range (nearly 300) of indigenous and exotic hosts. One of the few indigenous mistletoe's to regularly grow in urban situations.

Features

Woody, epiphytic much branched, bushy hemiparasite. producing multiple haustoria (these attaching at intervals long host branch) and epicortical, often spiraled roots. Leaves opposite, coriaceous. Petioles`5-50 mm long, flattened and slightly winged. lamina 30-60(-80) × 15-40(-68) mm, dark green to yellow-green, broadly elliptic, slightly ovate, ovate, obovate to rhomboid, base attenuate, apex obtuse to rounded. Inflorescences axillary, solitary of paired, in cymose panicles, these 10-15(-20) mm long with 8-9-12(-15) flowers arranged in threes. Flowers male, female or hermaphroditic (the dioecious condition most commonly seen when Ileostylus is parasitic on species of totara (Podocarpus spp.). Calyx cylindrical, presenting as an truncate rather obscure narrow rim 0.2 mm high. Petals 4, free, c.3-4 mm × 0.8-1.6 mm, greenish to yellow-green. Anthers 4, basifixed. Style contorted, usually initially coiled in middle, up to 3.0-4.5 mm long when uncoiled. Ovary 1-locular. Fruit a 1-seeded, 5-8 mm, yellow or orange, ellipsoid or globular (rarely ellipsoid-globular) berry. Seed 5.0-5.5 mm long, elliptic, rounded at both ends, terete.

Similar Taxa

Tupeia antarctica is often confused with Ileostylus. Ileostylus differs from Tupeia by its external rather than internal haustoria; having multiple haustoria and epicortical roots; by the styles of the flowers which are characteristically ‘bent’ rather than straight; by the yellow or orange rather than white or white spotted purple fruit; and by the young stems that are squarish rather than round (terete) in cross-section.

Flowering

September - December

Flower Colours

Green

Fruiting

December - July

Propagation Technique

Difficult. For best results use fresh fruit. Fruit should be squeezed gently so that seed is exposed. The exposed seed should be placed on a suitable host branchlet (ideally in dry weather so that the fruit does not wash off), and allowed to dry. Sometimes the fruit may need to be covered with netting to exclude birds. Then its up to the Gods! Seed almost always germinates (it will even germinate on glass) but unless an attachment is formed (and this may take months) the young plant soon dies. Some people find growing Ileostylus straight forward, others tricky. The process is often rather hit and miss and best results seem to be achieved when seed is placed on the same host plant (ideally the same genotype of the host) as that parasitized by the mother plant.

Threats

Not Threatened

Chromosome No.

2n = 22

Endemic Taxon

Yes

Endemic Genus

Yes

Endemic Family

No

Life Cycle and Dispersal

Fleshy berries are dispersed by frugivory (Thorsen et al., 2009).

This page last updated on 30 May 2015