- Biologists have discovered eight new species of “whip spiders” from the genus Charinus – arachnids with thin, long, whip-like legs – that live in the Brazilian Amazon.
- The distribution of these whip spiders is very restricted, and the eight new species are extremely vulnerable to environmental disturbances, researchers say.
- Study suggests that the newly described species should be considered to be included in the list of threatened species.
Amid collections of museum specimens, biologists have discovered eight new species of “whip spiders” from the genus Charinus — arachnids with thin, long, whip-like legs. This discovery nearly doubles the number of whip spiders’ species found in Brazil, according to a new study published in PLoS ONE. However, the newly described arachnids are already threatened by extinction, researchers say.
Whip spiders are sometimes also called “tailless whip scorpions”. But they are neither spiders nor scorpions. They belong to a group of arachnids called Amblypygi, which means “blunt rump”. Unlike true spiders, “whip spiders” do not have silk glands or venomous fangs, and they lack the characteristic tail of true scorpions.
Moreover, unlike spiders and scorpions, whip-spiders use only six pairs of legs to walk instead of eight. They do have an eighth pair of legs right in the front, which they use as a sensory probe, and not for walking. If you are a fan of Harry Potter movies, you might remember Mad-eye Moody demonstrating one of the three unforgivable curses on a whip spider. When the CGI critter lands on Ron Weasley, Mad-eye Moody calls the whip spider “lethal”. Whip spiders are, however, harmless to humans.
Identifying new species of whip spiders is not easy, researchers told LiveScience. It requires careful examination of tiny body parts under the microscope, such as differences in the structure of female genitalia, their whip-like limbs, and eyes. “If we compare all these things and see that it’s very unique, then we consider it a new species,” co-author Gustavo Silva de Miranda of the University of Copenhagen, told LiveScience.
The team named four of the newly described species after four scientists who have “contributed to arachnology”. They named the remaining four species after the habitat in which the whip spiders are found in the wild. For example, Charinus ferreus gets its name from ferrum (or iron), referring to the iron ore cave from where specimens of this species were collected.
In fact, most of the new species have been recorded from a handful of sites so far. “C. mysticus and C. eleonorae, for example, are recorded only from one cave or group of caves,” the authors write.
Since the distribution of these whip spiders is so restricted, they are extremely vulnerable to environmental disturbances, the authors add. For example, one of the new species, C. bichuetteae, is threatened by the imminent flooding that is expected to be caused by the hydroelectric dam of Belo Monte, located on the Xingu River in the Brazilian Amazon. Other new species such as C. carajas, C. ferreus and C. orientalis are endangered by iron mining in Carajás municipality and surrounding areas, the authors warn.
“Of the eight species here described, four are in regions of intense human exploitation or environmental modification,” the authors write. “Moreover, they are not known from other areas besides of the type locality and have small population size. For these reasons, these species should be considered to be included in the list of threatened species.”
With the discovery of the eight new species, Brazil is now home to 25 species of Amblypygi, the largest diversity of this group in the world.
“It’s good to discover these things before they actually disappear,” de Miranda told the Christian Science Monitor. “Because these cave animals, they only inhabit these caves and nowhere else. If we destroy their habitats, they are gone forever.”
- Giupponi APdL, de Miranda GS (2016) Eight New Species of Charinus Simon, 1892 (Arachnida: Amblypygi: Charinidae) Endemic for the Brazilian Amazon, with Notes on Their Conservational Status. PLoS ONE 11(2): e0148277. doi:10.1371/journal.pone.0148277