Felsurge Spider Egg

Source
This item can be looted from Felsurge Eggs. They also drop from the following aranasi in Faronaar in Azsuna:
 * Felsurge Broodmother
 * Broodmother Lizax
 * Felsurge Hunter
 * Felsurge Webspinner
 * Felsurge Spiderling

As a quest objective
This item is an objective of Disgusting, but Useful.