The island of wonderful snakes: Madagascar!
Madagascar is known for its diverse snake fauna (over 90 species) and the addition of new species locality data from a north-eastern rainforest show that this island has many extraordinary habitats harbouring incredible wildlife.
The snake biodiversity of the Ambodiriana forest in Madagascar has not been thoroughly explored, but some new observations help to highlight the high species diversity in the forest which could potentially contribute to the ongoing protection of that lowland rainforest site. The protected rainforest Ambodiriana is separated by Manompana river and includes a rich diversity of plant species, making it a great habitat for snakes to hide. The authors encountered species of 8 species that which were photographed in the field and identified (Fig. 1).
The snakes embody a great diversity in morphology and behaviour.
Compsophis laphystius is an arboreal nocturnal snake, known to prey on amphibians and their clutches.
Ithycyphus goudoti is known for its back fangs and mild envenomation when threatened. They are diurnal snakes that prey on different lizard species.
Ithycyphus perineti is one the largest lamprophid snakes in Madagascar, at 1.5 m. An interesting thing this snake does is when it is disturbed it can flatten its head to mimic a cobra, open its mouth widely and hiss very loudly.
Langaha madagascariensis is the most conspicuous snake of Madagascar because the male and female both look different to one another.
Madagascarophis colubrinus is probably one of the most common snakes of Madagascar with one of the widest distribution ranges. It occurs in every kind of habitat ranging from rainforests to houses in cities.
Parastenophis betsileanus is a nocturnal and partly arboreal species with a distinct coloration, consisting of white cross-bands on a dark brown ground coloration.
Phisalixella artifasciata is a reddish-brown specimen, with a distinct black cross-band in the neck.
Pseudoxyrhopus tritaeniatus is a relatively large nocturnal and terrestrial snake with a unique coloration consisting of five separated black stripes on the back on a red ground coloration.
The researchers were fortunate enough to see the feeding behaviour of two of the snakes in the wild, which is often rare. Augustine Kaloloha found I. perineti with its head hanging down from a small tree above the ground, constricting a leaftail gecko. The gecko was still alive when the researcher encountered the snake but only a few minutes later the gecko was paralyzed and subsequently died (Fig. 2). This is the first observation of I. perineti preying on a leaftail gecko. The researchers also observed a specimen of P. betsileanus one of the nights within the rainforest preying on a leaf chameleon (Fig. 3). P. betsileanus is also a terrestrial forager unlike other members of the genus. That is where it encountered the leaf chameleon amongst the leaf litter. These observations fill in a major distribution gap for I.perineti and P. betsileanus at Madagascar’s north-east coast.
Encounters of snakes are usually rare in Malagasy rainforests, except for the common species such as Madagascarophis colubrinus or Thamnosophis lateralis. With the presented observations, eight more serpent species are added to the previously published records on the herpetofauna of the Ambodiriana forest.
“Species inventories are a cornerstone for the justification and the management of conservation activities and can give crucial information on the condition of a protected area.”
Therefore, a high diversity of snakes in the forest is definitely a good indicator of the health of the forest.
Kaloloha, A., Misandeau, C. and Gehring, P.S., 2011. Notes on the diversity and natural history of the snake fauna of Ambodiriana-Manompana, a protected rainforest site in north-eastern Madagascar. Herpetology Notes 4: 397-402
Photographs taken by Florian Bernier (A), Ségolène Beaucent and Marc Fayolle (B, F), Chantal Misandeau (C, E, G), and David Ringler (D).