Caladenia whiteheadii facts for kids

Caladenia whiteheadii is a special type of plant from the orchid family. It grows only in New South Wales, Australia, meaning it's endemic there. This ground orchid has one hairy leaf and a single pale yellow flower. The flower has reddish tips on its sepals and petals. So far, it has only been found on one hill near Eugowra.

What Does the Whitehead's Spider Orchid Look Like?

Caladenia whiteheadii is a plant that grows from the ground. It is a perennial herb, which means it lives for more than two years. It also loses its leaves each year, making it deciduous. This orchid has an underground tuber, which is like a storage root.

Leaves and Stems

The plant has one dull green leaf. It is shaped like a spear and measures about 50 to 140 millimeters (2 to 5.5 inches) long. The leaf is about 7 to 13 millimeters (0.3 to 0.5 inches) wide. You might see red or purple spots near the bottom of the leaf. Both the leaf and the flower stem are very hairy. These hairs are clear or whitish and can be up to 4 millimeters (0.16 inches) long.

Flowers

A single pale yellow flower grows on a thin, wiry stem. This stem can be 150 to 300 millimeters (6 to 12 inches) tall. The flower itself is about 40 to 60 millimeters (1.6 to 2.4 inches) wide.

Flower Parts

• The dorsal sepal (the top part of the flower) is about 35 to 40 millimeters (1.4 to 1.6 inches) long. It starts wide at the base and then narrows to a reddish, sticky tip.
• The lateral sepals (the two side parts) are about 40 to 45 millimeters (1.6 to 1.8 inches) long. They are shaped like spears near their base and also narrow to a reddish, sticky tip.
• The petals are about 30 to 35 millimeters (1.2 to 1.4 inches) long. They are narrow and taper to a thin, sticky tip.
• The labellum (the special lower petal) is egg-shaped or spear-shaped. It is about 11 to 14 millimeters (0.4 to 0.6 inches) long and 8 to 10 millimeters (0.3 to 0.4 inches) wide. Its edges have up to eight pairs of red, thin teeth, each about 1 millimeter (0.04 inches) long. The tip of the labellum curls downwards. There are also four rows of red, mostly thin calli (small bumps) along the middle of the labellum.

This orchid usually blooms in September and October.

How Was it Named?

The Caladenia whiteheadii was first officially described in 2006. A botanist named David Jones gave it the name Arachnorchis whiteheadii. He wrote about it in a science paper called Australian Orchid Research.

Later, in 2010, another botanist named Gary Backhouse changed its name to Caladenia whiteheadii. He published this change in The Victorian Naturalist. The second part of its name, whiteheadii, honors Brian Whitehead. He was the person who first collected the plant sample that was used to describe this new species. This special sample is called the type specimen.

Where Does the Whitehead's Spider Orchid Grow?

This unique spider orchid has only been found in one specific place. It grows on a single hill near Eugowra in New South Wales. It lives in a forest area that has many shrubs.