How do I specify the type of space I want to create when creating spaces via the API?

[Michael Mulqueeny]

I'm able to create a generic space using the API, but I want to be able to specify that they are 'Knowledge base' spaces.  I'm able to do this via the WebUI but I'm having trouble identifying where to specify the space type in the API even after checking all the documentation I can find.  

This is what I'm using for the API Space creation and it works, I just can't specify 'Knowledge base' as the type of space I want to create.  Please help.  Thanks

curl --request POST \
--url 'https://<domain>/wiki/rest/api/space' \
--header 'Authorization: Basic xxxxxxxx' \
--header 'Accept: application/json' \
--header 'Content-Type: application/json' \
--data '{
"key": "SPACEKEY",
"name": "SPACE TITLE",
"description": {
"plain": {
"value": "SPACE DESCRIPTION"
}
}
}'