Photomicrographs from an eastern massasauga rattlesnake (Sistrurus catenatus) from Wisconsin

Photomicrographs from an eastern massasauga rattlesnake (Sistrurus catenatus) from Wisconsin, U.S.A. Periodic acid-Shiff. (A) On the ventral neck are multifocal areas of superficial to mid-epidermal necrosis (arrows). (B) Areas of necrosis often contain ~5-µm diameter branching, septate, PAS-positive fungal hyphae (arrowheads). (C) Skeletal muscle (m) underlying the dermis (d) is expanded and replaced by multifocal granulomas (arrow) containing fungal hyphae (arrowheads). (D) In the lung, faveoli are replaced by multifocal granulomas (arrows) containing variably dense accumulations of fungal hyphae (inset).