Sandstone truffle orchid facts for kids

The sandstone truffle orchid (scientific name: Arthrochilus byrnesii) is a special and rare type of flowering plant. It belongs to the amazing orchid family. This unique orchid grows only in the far north-west of Australia, meaning it is endemic to that area. It has three dark green leaves at its base. Its flowers are greenish and look a bit like insects. They also have tiny, dark reddish-black spots called glands on a special part of the flower called the labellum. Some scientists also know this orchid by another name, Phoringopsis byrnesii.

What Does the Sandstone Truffle Orchid Look Like?

The sandstone truffle orchid is a plant that grows from the ground. It is a perennial plant, which means it lives for more than two years. It's also deciduous, so it loses its leaves at certain times. This orchid has an underground tuber, which is like a small storage root. This tuber can grow new tubers at the end of root-like parts called stolons.

Leaves and Stem

Usually, this orchid has three dark green leaves. One leaf is larger, and the other one or two are smaller. Each leaf is about 150 to 300 millimeters (6 to 12 inches) long. They are also about 15 to 20 millimeters (0.6 to 0.8 inches) wide. The plant grows a flowering stem that stands about 150 to 300 millimeters (6 to 12 inches) tall.

Flowers and Their Parts

Along the flowering stem, you can find between five and fifteen greenish, insect-like flowers. Each flower is about 12 to 14 millimeters (0.5 inches) long. The flowers have different parts:

• The top part, called the dorsal sepal, is about 8 to 10 millimeters (0.3 to 0.4 inches) long and 3 millimeters (0.1 inches) wide.
• The side parts, called lateral sepals, are about 6.5 to 7.5 millimeters (0.3 inches) long and 2.5 millimeters (0.1 inches) wide.
• The petals are about 6 to 7 millimeters (0.2 to 0.3 inches) long and 1.5 millimeters (0.06 inches) wide. They are curved.
• The petals and side sepals bend backward against the ovary of the flower, so they are not very easy to see.
• The labellum is a special lip-like part of the flower. It is about 5.5 millimeters (0.2 inches) long and 2.5 millimeters (0.1 inches) wide. It sits above the rest of the flower.
• The labellum has a part called the callus. This callus is covered with many spiky, bristly, hair-like glands. These glands have a special tip that produces a sticky substance.

The sandstone truffle orchid usually blooms in March and April.

How Was This Orchid Discovered and Named?

The Arthrochilus byrnesii orchid was officially described for the first time in 1972. A scientist named Donald Blaxell studied a sample of the plant. This sample was collected near the South Alligator River. Blaxell published his description in a scientific journal called Contributions from the New South Wales National Herbarium. The plant sample he used was collected by another botanist, Norman Byrnes. This is why the orchid was named byrnesii after him.

In 2002, two other scientists, David Jones and Mark Clements, suggested changing the orchid's name to Phoringopsis byrnesii. However, not all scientists have agreed to use this new name.

Where Does the Sandstone Truffle Orchid Live?

The sandstone truffle orchid is a very rare plant that is not often seen. It grows in specific places in the north of the Northern Territory and the Kimberley region of Western Australia. You can find it growing around large sandstone rocks. It also likes to grow among clumps of tussock grass, especially a type of grass called spinifex.

How Does the Sandstone Truffle Orchid Reproduce?

Like other orchids in the Arthrochilus group, the sandstone truffle orchid needs help to make seeds. It is pollinated by male thynnid wasps. These wasps belong to a group called Arthrothynnus. Scientists don't know the exact species of wasp that pollinates A. byrnesii yet.

Besides making seeds, this orchid can also make new plants on its own. It does this by growing new tubers underground. This is a type of asexual reproduction, meaning it doesn't need seeds or pollen from another plant to create new orchids.