At top, the green arrow points to the interior view (shows the hingeline and muscle scars) of the brachial valve of an articulate brachiopod called Orthambonites sp. from the Middle Ordovician Badger Flat Limestone, Inyo County, California; specimen at left is a dorsal view of part of another Orthambonites sp. brachial valve.

At bottom is a closer look at the same Orthambonites sp. interior brachial valve that appears in the top image from the Middle Ordovician Bager Flat Limestone, Inyo County, California.