Round Island Keel Scale Boa
5
Round Island Keel Scale Boa
Megan Cluckey
Scientific Name
Task 1
Casarea Dussumeieri
Family: Bolyeriidae
Subtopic 1
Organism Description
The Round Island Keel Scale Boa is one of the rarest snakes in the world. It is non-venomous and can get up to 1.5 metres in length. The top side of the snake is usually dark in colour while the stomach area is lighter. Their bodies are covered with keeled scales, which is where the name comes from. It has also been observed that they change colour, being darker during the day and lighter at night. The snake is also very long and very thin, with flat heads.
Keeled scales vs Smooth scales
Begining of bottom jaw
Top jaw split
Eye Sockets
Specifics about species
Cladogram
Species: Round Island Keel Scale Boa ↓
Bolyeriidae (Used to be in the Boidae family but now classify as a new species family) ↓
Booidea ↓
Squamata ↓
Lepidosauria ↓
Reptile ↓
Animal ↓
Bolyeriidae
Bolyeridae
-Native to Mauritius, specifically Round Island
-Sepperated into two monotypic genera, but only one is extant
-Bolyeria: Extinct since 1975
-Casarea: Only known to be found on Round Island
Booidea
Booidea
-Superfamily of boa's and other boa-esk snakes. (Does not include pythons)
-Snakes in the superfamily (61 families) all shared a common ancestor about 68 million years ago.
Squamata
Squamata
Largest group of reptiles which includes snakes, lizrds and amphisbaenians (fancy word for lizard worms). These are all group together because of their scales. Also this is the sexong largest group of living vertebrates.
Lepidosauria
Lepidosauria
Reptiles with overlapping scales. The two most speciose of the group being lizards and snakes which contain over 9000 species combined.
Life Cycle
Subtopic 2
Breeding season is primarily in April though they do breed year round. Eggs are soft shelled and laid in batches of up to 12 at a time usually in trees and is watched by the female. They incubate for 90 days. When they are born they have a light orange colour and weigh less than 5 grams.
Food Sources
Subtopic 3
Geckos and Skinks
This could be the reason for their split jaws, which are held together by a joint just under the eye, and not many snakes have it.
The snakes usually feed during the day on skinks and lizards. They are not known to feed on mammals.
Current Population
About 1000
Subtopic 4
Reason for endangerment
Subtopic 5
Goats and Rabbits being introduced to the island devastated ecosystems for the long island keel scale boa. They are being removed from their habitat in attempt to help preserve the loss in species on the island.
What is being done?
Subtopic 6
The island is restricted to only scientist and conservationist. They have begun removing the rabbits and goats from the island in order to restore the natural vegetation of the island. They have also begun breeding the snake to preserve its numbers.
Location/Ecosystem
Task 2
Mauritius
Subtopic 1
Where they are from
The round island keel scale boa is from the Round Island of Mauritius. They are only there.
Ecosystem
Subtopic 2
The round island keel scale boa lives in in forests and savannahs. Loads of habitat has been lost due to goats and rabbits being introduced into the ecosystem.
Species also on the island
Subtopic 3
Round Island Skink
Round Island day Gecko
These species are what the Round Island Keel Scale Boa eat.
Goats & Rabbits
These species are killing the vegetation that the Boa needs to live.
Website Link
https://neverashash.wixsite.com/ksbproject
Website
Links
https://www.arkive.org/round-island-keel-scaled-boa/casarea-dussumieri/
https://www.worldlifeexpectancy.com/reptile-life-expectancy-round-island-keel-scaled-boa
https://www.researchgate.net/figure/Cladogram-of-evolutionary-relationships-of-Toxicofera-reptiles-Fry-et-al-2006-Vidal_fig1_221974827
https://en.wikipedia.org/wiki/%C3%8Ele_Ronde,_Mauritius
http://snakesarelong.blogspot.com/2012/04/round-island-splitjaw-snakes.html
https://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/splitjaw-snakes-bolyeriidae