Physogastrism
Guides
Gastrophysa
dock leaf beetles, knotweed leaf beetles
Gastrophysa is a genus of leaf beetles in the family Chrysomelidae, distinguished by pronounced physogastrism in females—swollen, membranous abdomens resulting from enlarged reproductive organs. The genus includes approximately nine described species, with G. viridula and G. polygoni being the most extensively studied. Members are oligophagous specialists on Polygonaceae, serving as both beneficial biological control agents for weeds and occasional minor pests of cultivated buckwheat. Several species have been introduced to North America and other regions, where they have established widespread populations.