Second largest pterotracheid; maximal size 200 mm. Proboscis, posterior part of trunk and tail cylindrical. Lateral folds of cutis on anterior one-third of trunk expanded as an oval disk; diagnostic for the species. Visceral nucleus length about three times width. Like Pterotrachea coronata, eyes rectangular in dorsal view, with length averaging 2.2 times retinal width. In contrast to the other species in this genus, P. scutata bears a wreath of two or three irregular rows of tiny peribuccal teeth along the entrance of the mouth (Vayssière, 1904).