The pectoral fin disc of the porcupine ray is evenly oval, almost as wide as long, and very thick at the center, giving it a domed appearance. The tip of the snout is rounded and barely protruding. The small eyes are closely followed by much larger spiracles. Between the narrow nostrils is a skirt-shaped curtain of skin the posterior margin of the curtain is strongly fringed and overhangs the mouth. The mouth bears three to five papillae on the floor and prominent furrows at the corners. The area around the mouth, including the curtain, are heavily covered by more papillae. Around 48 tooth rows are found in either jaw. The teeth are small and flattened. Five pairs of gill slits are located on the underside of the disc. The pelvic fins are small and narrow. The thin, rapidly tapering tail is about equal to the disc in length and has an almost cylindrical cross-section, without fin folds. The tail also has no venomous stinging spine, unlike other members of the family. A dense patch of flattened, heart-shaped dermal denticles covers the center of the disc and extends onto the tail. Larger individuals additionally have numerous tall, sharp thorns over the entire upper surface of the disc. The porcupine ray is plain light to dark gray or brown above, darkening to blackish towards the tail tip, and white below. This large species grows to at least 1.2 m (3.9 ft) across and 2.2 m (7.2 ft) long, and may reach 1.5 m (4.9 ft) across. Learn more about Porcupine Ray