Discovery of glow in the dark woodlice

Tuesday 24th January 2017

The Spiky yellow woodlouse (Pseudolaureola atlantica), also known as ‘the Spiky’, has been found to fluoresce under ultraviolet (UV) light. This Critically Endangered woodlouse is only found on St Helena, it has a striking prickly appearance and a tendency to live above ground on trees and ferns. This most recent finding is yet another unusual characteristic for such a bizarre animal. To date only one other woodlouse has ever been found to glow under UV, a trait more commonly known in scorpions; and the reason why these woodlice glow is currently a mystery.

This discovery has had some positive practical benefits. The Spiky is difficult to spot against the fern fronds they generally live on, but they become much more visible with a UV torch. Simple searches with the UV torch have already found Spikies in new locations, and detected far more individuals where they were already known to be, giving a much better idea of their distribution and true population numbers.

Amy-Jayne Dutton, St Helena National Trust commented “As many as 57 individuals have been counted in a 5 minute search, an astonishing number for a species whose population was originally thought to number 50 in its entirety.”

Although numbers are good in a few small patches there is still much to be done as they are still very rare; and so this important partnership project involves the St Helena National Trust, the St Helena Government, RSPB and Buglife; and is supported by the Darwin Initiative.

Providing and protecting habitat for the Spiky also provides a home for many other species, plants, invertebrates and more.

Vicky Kindemba, Buglife commented. “The Spiky is an important flagship invertebrate, representing many other endemic species, and the precious cloud forests it calls home. The endemic Golden sail spider is frequently seen during Spiky surveys and rare ferns are present in its habitat.”