In Western Australia, we are lucky to have a high diversity of reptiles. Within many of the reptile species, colours and patterns vary considerably between populations from different regions. This is brought about by the animals adapting to the different environments. Naturally, some colour and pattern ‘forms’ are rarer than others, causing their value in the pet trade to differ accordingly.
In WA, this is most evident within Stimson’s Pythons (Antaresia stimsoni) and South-West Carpet Pythons (Morelia spilota imbricata). Line breeding for specific colours and pattern in reptiles is slowly starting to emerge in WA, but is not as well developed as other states due to the WA pet reptile trade being relatively new. Below is a guide to help you identify some of the different ‘forms’ that you may encounter in WA when looking to buy a reptile and why prices may be different between animals even though they are the same species.
Stimson’s Python (Antaresia stimsoni)
These Stimson’s Pythons have a standard brown blotch with a lighter brown/cream background (often mottled).
As the name implies, these Stimson’s Pythons originate from the Wheatbelt region and typically have a much lighter, almost white, background compared to standard Stimson’s Pythons. Some specimens are also tri-colour (explained below). Due to the amount of clearing that has occurred in the Wheatbelt for agricultural practices, Stimson’s from this region are rarer to come across than those from other regions of WA. Not all Stimpson’s Pythons from the Wheatbelt conform to this description, many have the “common” colouration explained above.
These Stimson’s Pythons have a blotch which includes a light interior with a darker border. The background is lighter than either of the colours in the blotch, providing the third colour from which the name is derived. Stimson’s with this colouration are rarer than standard Stimson’s, especially ones from the Wheatbelt region.
These Stimson’s Pythons have a blotch which is larger than normal. This results in the lighter background being limited to fine lines.
These Stimson’s Pythons have a blotch which is reduced in size to the point where it is almost absent. This results in the background being dominant. These Stimson’s Pythons are not commonly found in the wild; they are generally specifically line bred by keepers in the pet trade.
South-West Carpet Pythons (Morelia spilota imbricata)
Common coastal form
These Carpet Pythons can originate from anywhare along the coastline, or on the Swan Coastal Plain. These snakes typically have a black blotch with green-brown background, but other colours and tones can sometime be found as a result habitat adaptations.
Hills form Carpet Pythons are also frequently referred to as “Black and white’s”. This name is derived from their colouring which consists of a dark dorsal (top) with a paper white ventral (belly). Black and white’s are rarer to come across than the common coastal form due to the restricted range they are found over in the wild.
These Carpet Pythons can vary in colour but have a blotch which is reduced in size. This results in the background being dominant. These Carpet Pythons are not commonly found in the wild; they are generally specifically line bred by keepers in the pet trade.
Due to the genetic diversity and range of habitats occupied by this species, colour can vary immensely. As this species is relatively rare in the wild and difficult to find because of its cryptic nature, low numbers are collected from the bush by licenced reptile takers. This has led to many of the wild colour forms being uncommon in the pet trade.