The Grove Quadwing is an enemy in Xenoblade Chronicles that are members of the Quadwing family. They can be found at level 81 - 82 at the tops of the trees of the Barren Moor in the Satorl Marsh but only at night. They can drop Quadwing Treasures, which are needed for the "Replica Monado 2" quest. Defeating ten of them is required to complete the "Nic's Final Test" quest.
It is also useful to know that they also drop a 3-slotted variant of the Meteor Nibbler, which is Riki's strongest weapon in terms of attack.