Wiki categories/archives page template

I am wanting to change the way a list of wiki articles appear on a category/archive page are shown. What is the template filename I need to use?

More details:
- I am creating a child theme for Nimble theme
- Want to change the template for URLs which use the wiki category slug ... .com/wiki/categories/mycat/
- Have tried category-incsub_wiki.php, category.php, category-mycat.php, none of them are picked up.

Any thoughts?
C.