Dark elbow orchid facts for kids

The dark elbow orchid, officially called Arthrochilus aquilus, is a special type of flowering plant that belongs to the amazing orchid family. You can only find this plant in one specific place: the northern part of Cape York Peninsula in Queensland, Australia. It usually has a few dark green leaves near its base. Its flowers are pale green and look a bit like insects, with tiny dark reddish-black spots called glands on a special part of the flower called the labellum.

What Does It Look Like?

The dark elbow orchid is a plant that grows from the ground. It's 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 storage part called a tuber. This tuber can grow new "daughter" tubers on the ends of root-like stems called stolons.

Leaves and Flowers

• The plant usually has two to five dark green leaves at its base.
• Each leaf is about 20–50 mm (0.8–2 in) long and 7–14 mm (0.3–0.6 in) wide.
• The plant grows a flowering stem that is about 200–350 mm (8–10 in) tall.
• This stem holds between three and fifteen flowers.
• Each flower looks a bit like an insect and is about 9–13 mm (0.4–0.5 in) long.

Flower Parts

The orchid flower has different parts:

• The top part, called the dorsal sepal, is about 7–8.5 mm (0.28–0.33 in) long.
• The side sepals are about 6–7.5 mm (0.24–0.30 in) long.
• The petals are about 6.5–7.5 mm (0.26–0.30 in) long.
• The petals and side sepals bend backwards towards the ovary (where seeds develop).

The Labellum

The most interesting part is the labellum. This is a special lip-like petal that helps attract pollinators.

• The labellum is about 6 mm (0.2 in) long.
• It sits on a small stalk, or "claw," about 4 mm (0.2 in) long.
• A part of the labellum called the callus is covered with many shiny, dark reddish, hair-like spots called glands.
• The very tip of the labellum has shiny black glands.
• You can see these orchids flowering from November to February.

How It Was Named

Arthrochilus aquilus was first officially described in 2004. A botanist named David Jones wrote about it after finding a sample in the Heathlands Reserve. This area is located near the very tip of Cape York.

The name aquilus comes from a Latin word. It means "dark coloured" or "blackish," which describes some of the dark spots on the orchid's labellum.

Where It Lives

The dark elbow orchid grows in forests. It is only found in the northern part of the Cape York Peninsula in Queensland, Australia.

How It Grows and Spreads

Like other Arthrochilus orchids, the dark elbow orchid needs help to spread its seeds.

• It is pollinated by male thynnid wasps. These wasps are from a group called Arthrothynnus.
• The orchid's flower looks and smells like a female wasp, tricking the male wasp into trying to mate with it.
• As the wasp tries to mate, it picks up pollen from the orchid and carries it to another flower, helping the orchid reproduce.
• Besides relying on wasps, this orchid can also make new plants on its own. It does this by growing new tubers underground.