Stinkbug
Reader Tiogshi Laj sends in this photo of a stinkbug taken a couple of months ago.
Stinkbugs come in several varieties, and depending on what kind of agriculture you’re doing they are either welcome friends or disastrous pests. Some species are carnivorous and will keep down your aphid population while many others attack plants, piercing the stalk with their beak to suck out the sap. Interestingly, it seems the actual removal of sap is less injurious to the plant than what they leave behind: they inject digestive juices into the plant with can damage it directly, and possibly worse, their beaks may be contaminated with virii or spores of plant diseases, inoculating the plant with a disease that can then spread to the entire crop.
So, I did some research on stinkbugs and found out two interesting things about their names. The first is about their latin name, family Pentatomidae, which means “five pieces”. Modern scholars don’t know if this is because their antennae have five segments or because their backs are visually divided into five distinct parts.
The second is about their common name. Stinkbugs produce chemicals that, well, stink. Different species make different specific chemical compounds, but they are all in a group known as aldehydes and are typically used as a defensive weapon. These glands are huge, relatively speaking: they can be filled with as much as 5% of the total weight of the bug. The chemicals are pleasant-smelling in very small concentrations (and may be used by the bugs to attract a mate), noxious in higher concentrations and may even be lethal if, for example, the stinkbug manages to get the chemicals onto the face of an attacking bug. I don’t know how common that last is, as it doesn’t look like stinkbugs can squirt their chemicals so much as just dribble them out. It seems the most likely bug to die from stinkbug stink is the stinkbug itself: scientists have learned that if they capture or transport them in an unventilated container, the aldehyde gas can get into their respiratory tract and asphyxiate them.