A saturnid sphinx is perhaps the most derived species of sphinx, being partly fey in nature and having many strange magical abilities. Saturnid sphinxes have an elf-like face with long, tapered ears lined with very long, sensitive hairs that greatly amplify their hearing. They have a somewhat bear-like body with muscular forelimbs and thinner hind limbs, a short, stout tail, and a pair of insect wings. What not in use, these wings appear very small and translucent; when it wishes to fly, the wings expand many times larger and darken to deep violet or blue and are often patterned with dramatic eyespots.

Saturnid sphinxes live among the branches of the Deep Woods, migrating to and from the canopy every evening. They seem to shun daylight and retreat from light sources brighter than torchlight when given the option. Unlike many other species of sphinx, saturnids can be male or female, and in another difference they are rather small, being about the size of an ogre when standing erect - an unlikely-looking but perfectly comfortable posture for them. They speak rarely, and tend to be cryptic and obtuse when they do. The elves of the Deep Woods treat them with awe and respect, believing that those who can prove their worth to the enigmatic creatures may gain a glimpse into their lost past. Wilden of the Deep Woods avoid them, because they're mostly full of shit and like to leverage their reputation as oracles to fleece the lesser races.