Myrmecodia

See text Myrmecodia is a genus of epiphytic plants, present in Indochina, Malesia, Papuasia, and Queensland, Australia.

This adaptation is to house colonies of ants, which live within the readymade chambers naturally grown by the plant.

Cavities are connected to the outer surface of the plant by small holes, which are naturally occurring and not created by ants.

[5][page needed] Hollow, smooth-walled tunnels form within the caudex with external entrance holes, providing an above-ground home for ant colonies.

This is advantageous because in most cases, although the plants are grown in situ, the tubers become too heavy and fall off of the tree they germinate on, eventually dying on the ground.

In nature, Myrmecodia tubers often grow hanging downward on bare branches without significant amounts of substrate, and thus depend upon symbiosis for most nutriment.

The plants store food and water in a greyish brown caudex that swells and grows spines over time.

The thick, unbranched stems are covered in clypeoli and alveoli which also grow spines and are densely filled with dry bracts.

Philidris cordata (formally Iridomyrmex cordatus) is believed to be the most common ant found occupying Myrmecodia species.

[4][page needed] All of these waste products stored within the rough-walled chambers begin to decompose when moisture is present, and are then broken down by microbial activity and the nutrients are then taken up by intrusive adventitious roots or absorbed through wall linings (rough-walls with root "bumps" lining the chambers).

[5][page needed] This symbiosis allows the plants to effectively gather nutrients (via the ants) from a much larger area than the roots ever could cover.

An illustration of the inner chambers of a Myrmecodia plant