Fecal-shield
Guides
Cassida rubiginosa
Thistle Tortoise Beetle
Cassida rubiginosa, commonly known as the thistle tortoise beetle, is a leaf beetle in the subfamily Cassidinae native to Europe and Asia that has been introduced to North America, New Zealand, and other regions as a biological control agent for invasive thistles. The beetle derives its common name from the tortoise-like appearance of adults, whose elytra and pronotum form a shield-like covering over the body. Both adults and larvae feed on thistle foliage, with larvae possessing a distinctive defensive structure—a forked caudal appendage used to carry accumulated feces and exuviae as a mobile 'fecal shield' that deters predators. The species has demonstrated effectiveness in reducing thistle biomass and seed production, though its host range extends beyond the primary target to other Cardueae species.
Hemisphaerota
Hemisphaerota is a genus of tortoise beetles in the subfamily Cassidinae, containing approximately 10 described species distributed across the circum-Caribbean region. The genus is characterized by hemispherical body shape and specialized tarsal structures for adhesion to host plant surfaces. The best-studied species, H. cyanea (palmetto tortoise beetle), exhibits remarkable defensive adaptations including adhesive tarsal pads that secrete oil when threatened, and larvae that construct protective fecal thatches.