Megacopta cribraria

Megacopta cribraria, also called the bean plataspid, kudzu bug, globular stink bug and lablab bug, is a shield bug native to India and China, where it is an agricultural pest of lablab beans and other legumes. The bug, while harmless to houseplants and people, often enters houses. It is attracted to white surfaces such as the walls of houses or white vehicles, because of the high reflectance of the white surfaces as it relates to the bugs' simple eyes. As a defense mechanism, they emit a foul-smelling pheromone that also acts as a congregation pheromone. Aside from smelling foul, the liquid also creates a burning sensation and sometimes leaves a red welt on bare skin. It is similar to other Plataspidae in having a somewhat unusual symbiotic relationship with its gut bacteria. Before laying eggs, females deposit particles containing the symbiont, which are then eaten by newly hatched nymphs under natural conditions. Nymphs experimentally deprived of access to the symbiont exhibited slower growth, smaller body sizes and higher mortality. Megacopta punctatissima, the Japanese common stinkbug, is a name applied to Japanese populations of M. cribraria. It has a gut bacteria that allows it to consume crops such as soybean plants. The two used to be treated as distinct species, but phylogenetic work has found the two to be not distinct. What is called M. cribraria in the United States likely descends from a population of "M. punctatissima" from Kyushu, Japan. The Japanese (JA) population is closest to the East Asian continental (EAC) population. The two diverged 0.71 Mya (million years ago), when the East China Sea land bridge became submerged. The EAC population branched off from the Southeast Asian (SEA) population 1.34 Mya. The bean plataspid gives off an offensive odor when touched, squashed, or poked. Hosted by wisteria, green beans, and other legumes, the insect sucks juice from the stems of soybean plants and reduces crop yield. However, when the insect infests kudzu, another invasive species, it appreciably reduces the growth of that plant.

from Wikipedia