Pterostylis micromega facts for kids

The Pterostylis micromega, also known as the swamp greenhood, is a special type of orchid. It is found only in New Zealand, meaning it is endemic there. Both plants that are flowering and those that are not have a group of leaves shaped like a circle at their base, called a rosette. When the plant flowers, it grows a single, fairly large, whitish flower. This flower has a unique pointed part on top, called a dorsal sepal. The color of its flower and its pointed dorsal sepal make it stand out from other Pterostylis orchids in New Zealand.

What Does the Swamp Greenhood Look Like?

The swamp greenhood is a plant that grows from the ground, not from a tree. It is a perennial plant, meaning it lives for more than two years. It is also deciduous, which means its leaves fall off at certain times of the year. This plant is a herb, which means it has soft stems, not woody ones like a tree. It grows from an underground tuber, which is like a small, round storage organ. Often, these plants grow together in loose groups.

Plants that are not flowering have a rosette of wide, oval-shaped leaves. Each leaf is about 35–50 mm (1–2 in) long. The stem that connects the leaf to the main plant, called a petiole, is another 5–10 mm (0.2–0.4 in) wide.

Flowering plants have a similar rosette of leaves at their base. From this base, a flowering stem grows, reaching about 150–380 mm (6–10 in) tall. This stem has egg-shaped leaves wrapped around it. The highest leaf on the stem is usually about as tall as the flower itself.

Each plant usually has one flower, which is mostly whitish with a light green tint. The top part of the flower, called the dorsal sepal, and the petals are joined together. They form a hood, or "galea," that covers the central part of the flower, called the column. The dorsal sepal is 25–40 mm (1–2 in) long and curves forward, ending in a pointed tip. The side parts of the flower, called the lateral sepals, stand upright. They have narrow tips that are taller than the hood. There is a wide space between these side sepals and the hood. The labellum, which is a special lip-like petal, is curved and reddish-brown. It sticks out above the space between the lateral sepals. You can see these flowers blooming between November and February.

How the Swamp Greenhood Got Its Name

The swamp greenhood, Pterostylis micromega, was first officially described in 1853. This description was written by a scientist named Joseph Dalton Hooker and was published in a book called Flora Novae-Zelandiae.

The second part of its scientific name, micromega, comes from two ancient Greek words. Mikros means "small" or "little", and mega means "large". It's interesting how a name can combine "small" and "large"!

Where the Swamp Greenhood Lives

The swamp greenhood likes to grow in wet, swampy areas. Sometimes, you can find large groups of them, with up to fifty plants growing together. In the past, this orchid was found on the North, South, and Chatham Islands of New Zealand.

However, its population has become much smaller over time. It hasn't been seen on Chatham Island since the 1800s. But you can still find it in some places on the North Island, like near Waikato, in the Volcanic Plateau area, near Wanganui, and in the Wairarapa region.

Protecting the Swamp Greenhood

The swamp greenhood is listed under the New Zealand Threat Classification System. It is currently classified as "data poor," which means scientists don't have enough information about it. It also shows "extreme fluctuations," meaning its numbers go up and down a lot, and it is "range restricted," meaning it only lives in a few specific places. This means it needs careful attention to make sure it continues to survive.