design mistletoe – What is the name of this control?

Can any one suggest a name for this check?

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It is designed to display nested hierarchical data, in much the same way as a TreeView control. However, unlike a tree, it can only display one list of items at a time, in the lower part of the control. The top half contains a list of all parent items – the user can access any level by clicking on the appropriate parent item.

I first stumbled upon this type of control on Betfair.com (from which also comes the data from this demo application). It is used to navigate through the different betting markets available.

For want of something better, I called it a StackView control, but there must be a more common term for this type of display.