This is a guest post by Sara Ruane, a postdoctoral fellow in the LSU Museum of Natural Science. In 2014, after more than 8 hours of hiking, Sara and a group of researchers from the American Museum of Natural History and from Madagascar came upon a snake in their path they had never seen before. Sara recently helped describe the new species, named Madagascarophis lolo, the “ghost” snake, in a paper in the journal Copeia.
Watch Sara describe why she is passionate about snakes and what kinds of physical characteristics she looks at when describing new species here.
Read about Sara's discovery below!
Sara is on Twitter at @Sara_and_Snakes, and will be doing a live Twitter chat on Sept. 8, 2016 from noon to 1pm Central U.S. time, so be sure to tune in and ask your questions about snakes!
Three Facts about Lolo the Ghost Snake:
1. While not venomous in the sense of having hollow, hypodermic style fangs attached to a venom gland, the snakes in the genus Madagascarophis are considered "rear-fanged." They have an enlarged tooth in the rear of their mouth and with a little bit of chewing, are able to work the toxins in their saliva into whatever they are chewing on. This not considered dangerous for people, but can cause a bit of a reaction at a bite site.
2. The word "tsingy," the name for the type of rock formations this snake was found among, is a Malagasy word that translates to "where one cannot walk barefoot."
3. While we don't know the exact diet of Madagascarophis lolo, snakes in this genus are among the most generalist, opportunistic snakes on Madagascar. They are known to eat frogs, lizards, birds, mammals, and even other snakes!
by Dr. Sara Ruane
In January and February of 2014, I went on an expedition to Madagascar to collect snakes.
As a herpetologist, being able to collect in Madagascar is basically a dream come true. The animals there have been evolving in isolation for tens of millions of years and so some of the most distinctive and unusual species of reptiles and amphibians in the world are found only there.
Lolo is the Malagasy word for ghost, and we thought this was an ideal name for a pale grey snake that has been eluding detection for so long.
I was collecting snakes for an NSF-funded project that aims to examine the patterns and processes of Malagasy snake speciation. The goal in this expedition was to collect DNA samples from the rarest and hardest to find snakes, in order to get a complete phylogeny or a family tree of pseudoxyrhophiines, the Madagascar snakes. We wanted to understand when these snakes got there and how they have managed to be so successful there. With these goals in mind, our field crew set out to find as many of the snake species for which there were no genetic samples available as possible.
Our field crew traveled around Madagascar in a Land Rover, through rain and mud and roads that were falling apart, all to find these elusive snakes. The rainy season is often the best time to look for snakes. That is when their prey, mostly frogs and lizards, are most active, meaning snakes are out looking for food.
The majority of snakes in Madagascar, called pseudoxyrhophiines, seemingly belong to a single radiation. It appears that an ancestral pseudoxyrhophiine managed to get to Madagascar, likely from mainland Africa, and that this only happened one time. Once there, this ancestral snake may have faced little competition from other groups of snakes and began exploiting all the resources, including food and habitat, across the island. Subsequent specialization by this ancestral species or the isolation of populations resulted in the roughly 90 pseudoxyrhophiine species we have there today.
The use of DNA to determine relationships among individuals or species is one of the most powerful tools we have as biologists. While morphology (how an organism looks) is extremely important for describing species and telling them apart, DNA contains additional information that we can also use to examine the relatedness of species. Essentially, the more closely related one species is to another species, the more similar their DNA will be (although in reality it can be a bit more complicated than that). We can take a sampling of loci (different chunks of DNA or genes) that are shared across snakes and then use how similar or different they are to estimate a phylogeny. The phylogeny shows how these pseudoxyrhophiines are related to one another.
Our field crew consisted of several herpetologists from the American Museum of Natural History, including Chris Raxworthy and Frank Burbrink, and then a local field crew in Madagascar. I was a postdoctoral researcher at the American Museum of Natural History at the time. The local crew included researchers and students from Malagasy Universities such as Université de Mahajanga.
Prior to leaving, we compiled a list of target snakes and at which field sites we were likely to find them. After having great success at our first couple of field sites at the very northern end of Madagascar, we traveled slightly southwest to Ankarana National Park. Ankarana is famous for its tsingy, or limestone rock formations. Tsingy is very sharp and pointy and difficult to walk on. Our focus here was on a rare snake called Alluaudina mocquardi, which has only been collected by scientists two times prior and with no DNA samples ever taken. The area where the previous Alluauadina mocquardi had been collected was our goal, although it was over 25 km to get there via hiking.
With the aid of hired porters, we hiked to the field site and spent about a week there in ceaseless rain. And while we did get some interesting snakes and other reptiles there, we did not find the target species. So after a week, we packed up and headed back to the park entrance.
Despite having spent the entire day walking, part of our field team, myself included, decided to explore an area of the park that had been opened only recently, where a path had been made accessible across the tsingy. Just past dusk, as we walked down the path, team member Bernard Randriamahatantsoa, a master’s student from Université de Mahajanga, reached down and picked up a snake. This snake was easily identifiable to the genus Madagascarophis, but was a pale gray color no one, including Chris Raxworthy who has been working in Madagascar since the 1980’s, had ever seen before. While this snake was not our target, it was an exciting find.
We ended up finding the target species, Alluaudina mocquardi, the next evening, and so we were extremely pleased. We continued our trip, traveling to several other sites and finding other rare pseudoxyrhophiines across Madagascar.
Once back in the USA, I was able to take the genetic sample from this odd-looking Madagascarophis and sequence several loci and compare them to other species in the genus and to other pseudoxyrhophiines. The genetic information indicated this snake is related to but is quite different from other Madagascarophis. Its closest relative is another recently described species, M. fuchsi, which is found further north and from which we had collected a sample earlier on the trip. Combined with the distinct morphology of this snake, it seemed we had a new species.
We took detailed quantitative and qualitative data from the specimen and compared it to other species and wrote up our comparisons, along with the inferences we were able to make based on the genetic dataset. We decided to name the snake “Madagascarophis lolo.” Lolo is the Malagasy word for ghost, and we thought this was an ideal name for a pale grey snake that has been eluding detection for so long. The description of the new species Madagascarophis lolo is now a publication in the journal Copeia.
- ‘Ghost Snake’ Discovered in Madagascar, LSU Press Release