Nepenthes mirabilis

Nepenthes mirabilis (common names include monkey cups, tropical pitcher plant, and common swamp pitcher plant) is a carnivorous plant native to Southeast Asia. Nepenthes mirabilis is the most widely distributed of all Nepenthes species, and can be found in many countries including China and Australia. Pitcher plants are the best-known type of carnivorous plant after the Venus flytrap. Nepenthes and Sarracenia are the two families of pitcher plants.  

The pitchers of Nepenthes mirabilis are actually a modified leaf that is adapted to a cup-like shape that holds a reservoir of digestive fluid containing enzymes that break down organic matter. Of all the methods that carnivorous plants use to trap prey, the pitcher is the most simple and passive. 

Nepenthes mirabilis uses its pitchers to attract and trap its prey, which generally consists of crawling or flying insects like ants, flies, and wasps. The insects are attracted to the pitchers by their bright colors and nectar. Once insects land on the slippery rim of the pitcher, they slide down into the trap into the liquid collected there. A waxy substance coating the inside of the pitcher keeps insects from being able to crawl back out. Once submerged, the insect is unlikely to be able to escape and soon drowns. 

Nepenthes mirabilis grows in environments where nutrients are hard to come by, which is why they evolved to supplement their diet with living organisms. After the prey is broken down by the enzymes produced inside the pitcher, the plant can access the available essential mineral nutrients, especially nitrogen and phosphorus. 

Although it mainly traps insects, there have been cases where a Nepenthes mirabilis captured some larger prey. Since spiders and lizards eat the same types of insects that are attracted to the pitchers, they can often be found spending time around a pitcher plant. They can also easily slip into the digestive liquid and become food for the plant as well. On the other hand, a certain species of tree frog has actually been found living inside the pitchers of Nepenthes mirabilis and feeding on the insects that appear there. It is thought that the frog is not damaged by the digestive liquid because it is covered in a slimy coating that protects it. 

Another amazing fact about Nepenthes mirabilis (and other Nepenthes species) is that it actually produces two different types of pitchers. The upper pitchers grow on the climbing stems and are adapted to capture flying insects. Meanwhile the lower pitchers grow near or on the ground, and include ladders or wings that crawling insects can use to access the pitchers. Younger plants may have only lower pitchers, with upper pitchers developing as the Nepenthes matures. The two types of pitchers usually look so different that it seems like they shouldn’t even be on the same plant!  

Compared to other varieties of pitcher plant, Nepenthes mirabilis has thin, papery leaves that are suited to a humid environment similar to the hot and moist areas where they grow wild. For those wanting to raise Nepenthes mirabilis as a houseplant, the most important element is to provide plenty of bright, indirect sunlight and high humidity. It may be useful to grow Nepenthes mirabilis inside a terrarium in order to provide it with enough moisture.