A new species of snake discovered in a limestone "forest" in Madagascar has been given the species name lolo – the Malagasy word for ghost – in a nod to its elusive nature and eerily pale colouration.

Image: Sara Ruane/LSU

As we've seen many times before, new species can find you when you're not looking for them – and the discovery of the "ghost snake" was no different. Researchers had been tracking another species within Madagascar's Ankarana National Park back in 2014 when the unusually pale reptile caught their eye on a path that had just recently been cleared

The snake belongs to the genus Madagascarophis, a group also known as the Malagasy cat-eyed snakes. These mildly venomous reptiles have distinctive vertical pupils, a feature often found in snakes that are active in the evening hours and at night. But the new species stands out amongst its kind thanks its unusual colouration.  

"None of the other snakes in Madagascarophis are as pale and none of them have this distinct pattern," says Sara Ruane, a post-doctoral researcher at the Louisiana State University Museum of Natural Science.

Iconic limestone Tsingy rocks in Ankarana National Park in northern Madagascar where the ghost snake was discovered. Image: Sara Ruane/LSU

Aside from its unusual hue, the snake's choice of habitat also sets it apart. While many of the island's cat-eyed reptiles can be found in forests or more developed areas, Madagascarophis lolo (pronounced "luu luu") was discovered in an area of Ankarana covered by dramatic limestone spires, known as tsingy.

"Even though the cat-eyed snakes could be considered one of the most common groups of snakes in Madagascar, there are still new species we don’t know about because a lot of regions are hard to get to and poorly explored," says Ruane.

Tracking down Madagascar's slithering wildlife is certainly no walk in the park – in fact, the team made their discovery after 17 miles of hiking in near-constant rain. To boost their chances of finding snakes, researchers prefer to conduct fieldwork during the island's rainy season, when snakes are out in full force hunting their lizard and frog prey. 

"It was really tough," recalls Ruane. "It was a lot of work, but the payoff was big. Snakes are hard to find under the best of circumstances. They are pretty elusive."

LSU post-doctoral researcher Sara Ruane in the field in Madagascar. Image:  Sara Ruane/LSU

After returning to the US, the team performed a series of genetic and morphological tests to confirm that their discovery was indeed a new species. The results of that research were published in the journal Copeia last week. 

Counting all of the scales on the animal's back, belly, eyes, and upper and lower lips was just the start. The researchers also extracted DNA from tissue samples in order to find out how similar the ghost snake is to other members of its group. It turned out that its closest living relative is a snake known as Madagascarophis fuchsia, which was discovered a hundred kilometres north of Ankarana several years ago, in a similarly rocky, isolated area.

The team also managed to map the genetic family tree for the entire Madagascarophis group, which contains five different species. For Ruane, the newest addition is proof that more discoveries are just waiting to be made. "If this commonly known, wide group of snakes harbours this hidden diversity, what else is out there that we don't know about?"


Top header image: Sara Ruane/LSU