Bug experts have been astonished by the rediscovery of one of St Helena’s smallest creatures. Conservation officer Lourens Malan was lucky to spot the missing leaf hopper on his day off: it’s only three millimetres long.
by St Helena Government writer
St Helena is a small island, but it is still possible to lose things. Just occasionally, however, they turn up again.
The 3mm-long leaf hopper Chlorita edithae was described from eight specimens collected by Vernon Wollaston during his visit to the island in 1875 and it hasn’t been seen since – until now.
On the 1 April 2013 bank holiday, while exploring tiny fragments of remaining natural vegetation above Wranghams on the high central ridge of the island, Lourens Malan noticed a few brightly-coloured leaf hoppers.
Quickly grabbing his camera, he managed to get several photographs of them. He later showed these to David Pryce, invertebrate conservation co-ordinator at the St Helena National Trust, who nearly fell off his chair – it hadn’t been seen for 137 years.
This major discovery is all the more important as the hopper was found on the endangered endemic Whitewood Tree, of which there were only 80 surviving in 1995.
Active conservation work on the Island has helped safeguard this species for the immediate future.
Most of the new stock has been grown from seedlings collected from the wild, and then grown on in more accessible areas where they could be tended and monitored.
As the plants collected were small it is less likely that they will provide habitat for the creatures associated with them.
Many of these insects are very poor at dispersing, which also restricts their ability to form new colonies.
Discoveries like this mean that steps can be taken to conserve these species as well as their plant hosts.
The isolated island of three Whitewood Trees where the hopper was found is in a sea of invasive New Zealand Flax.
This shows how rare invertebrates can persist for long periods in very low populations.
It is hoped that future work by the National Trust and the government’s environment staff will uncover more of these isolated pockets.
The UK’s Buglife charity is supporting the work, through a three-year project funded by the British government’s Darwin Initiative.
Their health will be assessed by looking at the diversity of their invertebrate populations. Conservationists hope more discoveries – and rediscoveries – will be made.
Tara Pelembe, Head of the environment division, said: “We are very excited about this find.
“Our rarest plants and animals exist in tiny pockets of native habitats. These unique habitats need to be safeguarded.
We are very pleased to be working in partnership with the National Trust and Buglife on a much-needed Darwin invertebrate project, which will help us to better understand the invertebrate species and habitats that exist on this unique island.”
Lourens Malan is a terrestrial conservation officer in the Environment Management Division of St Helena Government.