Madagascar, the world’s third largest island, is famous for its endemic fauna and flora. More than 80 percent of Madagascar's ~15 000 plant species are found nowhere else in the world, including five entire families. Lemurs have been characterized as "Madagascar's flagship mammal species" by Conservation International and there are about 100 known species all endemic to the island. The list goes on and on. 60% of the bird species can only be found on Madagascar and about 99% of all the frog species (more than 300). Although invertebrates remain poorly studied on Madagascar, researchers have found high rates of endemism among the known species, e.g. all 650 species of terrestrial snail are endemic, over 90% of the ants as well.
Some millipedes also represent quite charismatic invertebrate endemics of Madagascar. These include the large-bodied, strikingly red-black colored so-called Fire-Millipedes of the order Spirobolida , and the giant pill-millipedes, locally called ‘Tainkintana’ (star droppings), reaching the size of a small orange or a tennis ball when rolled-up. The giant pill-millipede genus Sphaeromimus is a rather unusual representative of the order. One characteristic of the genus is the presence of well-developed stridulation organs which means these animals produce sound by rubbing together certain body parts. These stridulation organs are still not well understood, but may play a role during courtship and earned the genus the name chirping giant pill-millipedes.
An international team of researchers has now published an integrative inventory (morphology and DNA Barcoding) of chirping giant pill-millipede species in Madagascar which revealed seven new species, many of them microendemics. These microendemics that can only be found in small forest fragments, less than a few hundred meters long and wide, are very likely threatened by ongoing rainforest destruction.
Since the arrival of humans around 2,350 years ago, Madagascar has lost more than 90 percent of its original forest. This forest loss is largely fueled by traditional slash-and-burn agricultural practices that had been already used by the earliest settlers. The extensive habitat destruction, hunting, and harvesting for the ornamental animal trade have threatened many of Madagascar's endemic species or driven them to extinction, e.g. at least 17 species of lemur have become extinct since man arrived on the island.
The newly discovered millipedes might vanish very quickly. One of them (Sphaeromimus lavasoa), is restricted to the Lavasoa Mountain, which is covered by an isolated, slightly larger than 100 hectare, rainforest remnant, which is famous for the recent discovery of a large scorpion as well as a dwarf lemur species.
Another new species (Sphaeromimus saintelucei) is probably the most endangered millipede on Madagascar. It was found in a fragment of the Sainte Luce littoral rainforest characterized by its laterite soil that is now so small that no lemur or other large vertebrate species can survive in it. It is also home to another species (Sphaeromimus splendidus) also believed to be a microendemic. Despite their close proximity, both species are not even closely related. They are only found in two very small rainforest fragments which are currently threatened by a titanium ore mining project. There are intentions to designate and manage conservation zones but current plans include only one large fragment that might not even include the last refugia for these species