Clubbed elbow orchid facts for kids

The Clubbed elbow orchid (scientific name: Arthrochilus irritabilis) is a special type of flowering plant in the orchid family. It's known for its unique, insect-like flowers. This orchid is mostly found in Queensland, Australia. It has a few leaves and can grow many light green or reddish flowers. These flowers have tiny, hair-like parts on their "lip" (called a labellum). There's also one record of this orchid being found in Papua New Guinea.

What it Looks Like

The Clubbed elbow orchid is a perennial plant. This means it lives for more than two years. It's also deciduous, so it loses its leaves during some seasons. This orchid grows from an underground part called a tuber. This tuber can make new "baby" tubers on root-like parts called stolons.

Leaves and Stem

Each orchid plant has between three and five leaves. These leaves are narrow and shaped like a spear. They are bluish-green and grow from the base of the flowering stem. The leaves are about 30–80 mm (1–3 in) long and 8–14 mm (0.3–0.6 in) wide.

The flowers grow on a thin, strong stem. This stem can be green or reddish. It stands tall, between 120–350 mm (5–10 in) high. On this stem, you can find anywhere from five to thirty flowers.

The Flowers

The flowers of the Clubbed elbow orchid look a bit like insects. They are light green or reddish. Each flower is about 10–14 mm (0.4–0.6 in) long.

Flower Parts

• Dorsal Sepal: This is the top part of the flower. It's about 8–11 mm (0.3–0.4 in) long and 2 mm (0.08 in) wide. It's folded lengthwise and points downwards.
• Lateral Sepals: These are two side parts of the flower. They are oblong (like a stretched circle) and curved. They measure 5–7 mm (0.2–0.3 in) long and about 1 mm (0.04 in) wide.
• Petals: The petals are thin and straight. They are also 5–7 mm (0.2–0.3 in) long and about 1 mm (0.04 in) wide. Both the lateral sepals and petals curve downwards towards the flower's base (the ovary).
• Labellum: This is the special "lip" of the orchid. It's about 5 mm (0.2 in) long and 1 mm (0.04 in) wide. Its base is reddish. The labellum has a part called a callus that looks like an insect. This callus is about 2.5 mm (0.1 in) long. It's covered with many hair-like, reddish or purplish glands. The very tip of the callus is about 1 mm (0.04 in) long and has shiny, blackish glands.
• Column: This is a curved part of the flower, about 7–8 mm (0.28–0.31 in) long. It has two pairs of curved, triangular "wings."

This orchid usually blooms between November and February.

How it Got its Name

The scientific name Arthrochilus irritabilis was first officially described in 1858. This was done by a scientist named Ferdinand von Mueller. He wrote about it in a publication called Fragmenta phytographiae Australiae. The plant he described was found near Moreton Bay.

The second part of its scientific name, irritabilis, is a Latin word. It means "easily excited." This name likely refers to how the orchid's labellum (lip) moves when touched, which helps with pollination.

Where it Lives

The Clubbed elbow orchid grows in different types of places. You can find it in woodlands, forests, and areas with low, woody plants called heath. Sometimes, many of these orchids grow together, forming large groups.

It is very common and widespread in Queensland, Australia. You can find it between the towns of Ingham and Brisbane. There is also one known sighting of this orchid in Papua New Guinea.

How it Survives

Like other Arthrochilus orchids, the Clubbed elbow orchid has a special way of being pollinated. It relies on male thynnid wasps from a group called Arthrothynnus. The specific type of wasp that pollinates A. irritabilis isn't fully known yet. The orchid's insect-like labellum tricks the male wasp into trying to mate with it, and in doing so, the wasp helps spread the orchid's pollen.

Besides relying on wasps, this orchid can also make new plants on its own. It does this by producing new tubers underground. This is a way of reproducing without needing seeds or pollination.