This is one of the few quests in the Nektulos Forest Timeline that doesn't require Neriak citizenship. <—- This seems incorrect to me.
As they take place in the same area and at the same level, it is recommended that you also get the quest Finding Millie and do them together.
If you speak to Zintra again after the quest is complete she will ask if you want her to show you the results of the quest. If you say yes, she will apply a drachnid illusion on you. The effect has no duration and can be reapplied whenever you want!
From the main road between J'Rais Bridge and N'Mar's Ascent, take the path east that leads to the owlbears. The spiders will be all along the road next to rocks, nearish ( -615, 30, 40 ) /waypoint -615, 30, 40.