Mucai Shale

The Mucai Shale (also spelled Mutsai Shale in some literature) is a geologic formation in the heartlands of the Aurlûnor Velande. It is notable for being the rocks where fossils of the early plant Pangninia and early fungus Prototaxites were found.

The rock itself is a small section of marine and coastal-alluvial sedimentary rocks of the late Tudenanian period, ranging from 470 to 464 million years old. It is overlaid unconformably by the extrusive Melwende Andesite and the sedimentary Sokalis Coal Measures. It is underlaid by the extensive West Elendor Slate, which itself may contain metamorphosed parts of the older Liangsire Member. The exact border between the WES and Mucai Shale is debated among many geologists.

While known for its terrestrial fossils, the vast majority of the fossils known from the Mucai Shale are aquatic. Orthoceras and several miscellaneous brachiopods and bryozoans are known from the Liangsire Member; the Pangnin member contains the plant and fungal remains, as well as several invertebrate burrow ichnofossils.