The male lesser water boatman, aka Micronecta scholtzi, can create mating calls as loud as 99.2 decibels, which is the equivalent of sitting in the front row of a loud, full-blown orchestra, or standing 15 meters away from a hurtling freight train....

...To make this colossal acoustic din, the male water boatman rubs his penis (or “genitalia appendage”) against the ridged surface of his abdomen, like a wooden spoon against a washboard

So while an African elephant’s rumbling call can be 117 decibels, if the trunked beast was reduced to the size of a water boatman, the marine insect would far outclass it. As would, it turns out, a snapping shrimp, a speckled bush cricket, a bronze dainty frog, an alligator and a human.