Glowing Cave Mushroom
The Glowing Cave Mushroom is found at [48.7, 47.5] inside the Waning Crescent on the way to Light's Fall in central Shadowmoon Valley. Find it on a small cliff near a waterfall at the southern extent of the cave. It contains 10-20 Starflowers.
In the north fork of the cave, keep an eye out for the Dark Emanation, which drops the 
[Abberant's Paw] and 10-20x 
[Garrison Resources]. Beyond that, there is a Hanging Satchel hanging above the west entrance to the cave. Get to the satchel by running from the east entrance of the cave in Light's Fall and jumping up the cliffs to get back to the area. It contains the 
[Cragsman Gloves], 3x 
[Potion of Slow Fall], and 10-20x [Garrison Resources].
Tracking quest
To check whether the glowing cave mushroom has been looted, copy and paste this command into the chat window:
/run print(C_QuestLog.IsQuestFlaggedCompleted(35798))
If a "true" appears in the chat window, the glowing cave mushroom has been looted; "false" indicates the opposite.
Patch changes
Patch 6.0.2 (2014-10-14): Added.