Nevus Araneus (Spider Nevus; Spider Angioma; Vascular Spider) By Denise M Aaron, MD, Dartmouth Geisel School of Medicine Reviewed / Revised Jan 2022 | Modified Sep 2022 View Patient Education Diagnosis Treatment Topic Resources Spider Angioma Nevus araneus is a bright red, faintly pulsatile vascular lesion consisting of a central arteriole with slender projections resembling spider legs.