A 10-year hunt for a tiny parasitic ghost orchid

A 10-year hunt for a tiny parasitic ghost orchid

Would you have the patience to spend 10 years trying to find something practically invisible? Botanist Carlos Lehnebach recently discovered his ‘holy grail’ a collection of tiny ghost orchids in the Wellington region. 

Digital editor Rachael Hockridge got to see them for herself, and quizzes Carlos on why these plants are so special – and bizarre.

Getting the shot

It’s mid-winter, and four of us have been lying on the forest floor for over an hour now. It’s getting cold, and our joints have seized up.

We have to stay in the same careful position – holding flashlights, cameras, and pens – while not squashing a group of tiny, colourless, ghost orchids.

We need a photo of the tiny orchids in the foreground, and  Carlos Lehnebach staring lovingly at them in the background (he’s pointing at them with a pen and wearing an awesome magnifying visor.)

Man on the ground in a forest
Carlos orchid hunting, 2019. Photo by Rachael Hockridge. Te Papa

Because the plants are tiny and practically colourless, it’s a hard shot to nail, even for the New Zealand Geographic photographer who’s directing the shoot. But another hour later, we think we have a useable photograph (you’ll have to look in September’s copy of New Zealand Geographic to see how they turned out).

Two hours felt like a long time to be staring at the same alien-like plant, but Carlos has been hunting for this orchid for over 10 years.

Trying to get the ghost orchid shot, 2019. Photo by Rachael Hockridge. Te Papa

A 10-year hunt

When Carlos moved to Wellington in 2008 and started working at Te Papa, he found a book on New Zealand orchids which featured a peculiar species found in the lower North Island – the ghost orchid.

He had a good idea where it should be growing, and committed to finding it.

Every year he’s been coming to the same area trying to figure out where it grows.

Last summer, he spotted some long stems with fruits developing at their ends. “That’s the best time for you to spot the plant,” says Carlos, “because there’s something sticking out of the leaf litter.”

Carlos shows one of the long stems with fruits developing, 2019. Photo by Carlos Lehnebach. Te Papa

He marked the place, and every month since March he’s been walking half an hour up a steep hill to check for signs of flower growth, and, in July, his patience was rewarded with a handful of flowering ghost orchids.

Ghost orchid, 2019. Photo by Rachael Hockridge. Te Papa

What’s a ghost orchid?

Ghost orchids (Corybas cryptanthus) are related to New Zealand spider orchids in the genus Corybas. They’re endemic to New Zealand, and found nowhere else in the world.

They’re particularly hard to find because they’re winter-flowering, small, and they don’t have leaves. They also doesn’t have chlorophyll at all – so they’re clear.

A parasite

Ghost orchids are a kind of parasite. They can’t produce their own food so they uses fungi to steal food from other green plants that are photosynthesising.

This particular collection of ghost orchids Carlos thinks are offshoots of one plant.

Up-close to the ghost orchid, 2019. Photo by Carlos Lehnebach. Te Papa

Plants that don’t have chlorophyll

In his current research, Carlos is trying to figure out why some plants stop photosynthesising and go into this parasitic lifestyle, and how much genetic rearrangement happens to make that possible. This is a study in collaboration with scientists from Massey University, Dr Richard Winkworth and MSc student Katherine Murray.

“About 500 species of plants in the world don’t have chlorophyll, and nearly half of them are orchids. In New Zealand we have about six species of these,” says Carlos. “Also, of the almost 120 species of Corybas in the world, this is the only one that doesn’t have chlorophyll – so it’s really unique to New Zealand and probably evolved here.”

Ghost orchid, 2019. Photo by Rachael Hockridge. Te Papa

How rare is a ghost orchid?

Because they’re so hard to find, and we don’t know enough about what habitat they grow in, DOC have included them in their list of species of conservation concern. They’re currently ranked as ‘At Risk – Naturally Uncommon.’

At Te Papa we have one specimen in the collection, collected in the 1950s in the Wellington area. That’s how Carlos knew the general area he might find one in.

Keeping them a secret

As we leave, Carlos conceals the spot by sprinkling leaf litter over the area we’ve disturbed. We need to protect these rare orchids – which includes keeping the area where they grow secret.

“It’s a great discovery,” exclaims Carlos.

Carlos, 2019. Photo by Rachael Hockridge. Te Papa

6 Comments

  1. Avatar

    This is a great find indeed as this is a biogeographically interesting group. If I understand correctly, the NZ species are a sister group to Australian species which would be consistent with a vicariance origin. Some publications have asserted that the orchid dispersed to NZ recently, but since molecular divergence estimates are based on fossil calibrations they can only generate minimum dates that place no constraint on the maximum age of this orchid.

  2. Avatar

    Well done Carlos! You da Man!

  3. Avatar

    Yay, Carlos, my friend! Most happy for you, me! Achievement! Big achievement! Yay!!!!!

  4. Avatar

    Well done Carlos. What amazing plants and plant hunter!

  5. Avatar

    Congratulations and well done

Leave a comment