Mysterious SharePoint MOSS page templates appearing in site collection

Question

Hi

I have previously created a couple of page layouts in SharePoint designer and used these throughout a site collection. Everythings was fine. When choosing create page, I would be able to choose the from the following templates:

(WCM Page)Stock Control Page
(WCM Page)Sub Site Home Page

Now in addtion some mysterious page layouts have appeared from nowhere and all current pages have those new page layouts assigned:

(WCM Page)en-us/Preview Images/Stock Control Page
(WCM Page)en-us/Preview Images/Sub Site Home Page
(WCM Page)Stock Control Page
(WCM Page)Sub Site Home Page

Does anyone know why these may have suddenly appeared?

Thanks for any pointers.