The Spiny Terrapin (Heosemys spinosa) or Spiny Hill Terrapin or Spiny Turtle is a globally endangered species of forest terrapin.
It normally inhabit rainforest near shallow, clear streams. Normally it camouflage itself well among the leaf litter and can be more easily spotted once it moves.
It is named as such because the juveniles have a carapace which is heavily serrated at the margin. As it grows older, this is worn down. So one can tell whether it is a juvenile or adult by looking at the extent of the spines. The purpose of the spine is believed to be defensive in nature, so as to prevent predator from swallowing it whole. Perhaps as it grows older and bigger, such spines are no longer essential.
On a very wet day at Sime Forest in July 2012, I had the misfortune to have the main exit from the trail flooded. Even after the rain subsided, the stream was too overflowing with water to cross safely. So I decided to make a long detour to another exit. This entail climbing up a hill and descending. It was not a pleasant thing to do, considering that the descending part was waterlogged as well.
(Dillenia Hut flooded, as well as the nearby stream where I normally cross to exit. Photo taken from my phone.)
As I was navigating my way down slowly, I noticed something moving on the side of the trail where the leaf litter gathered. It was a turtle. On closer examination it turns out to be a juvenile Spiny Terrapin. A rare find indeed!
I had only my birding lens with me, so even though it wasn’t going anywhere fast, I had to step back quite a bit to take some pictures of it. Poor terrapin had a few mosquitoes hovering and biting it. As it was after the rain, the place was rather misty and humid.
It slowly but deliberately tried to navigate itself from one side of the trail to another. As the trail was a down-slope with soil erosion, not much vegetation cover was around, so that proved to be good for photography. Once it crossed to the other side, I had no motivation to track it further. After all, the mosquitoes were not only after turtles, and I beat a hasty retreat down the slope.
It seems that on another encounter of the juvenile spiny terrapin was also after rain1. Perhaps they prefer to come out when the forest floor is wet and humidity is high. I can only speculate of course.
A short video and the photo gallery of the terrapin is below.
Photo Gallery
Reference:
1. Juvenile spiny terrapin at MacRitchie forest (PDF)