amphizoa
Amphizoa insolens - trout stream beetle
California
Amphizoa are among the more enigmatic insects I've photographed. These dime-sized beetles are found only in the mountains of China and western North America, a disjunct distribution paralleled by a number of interesting taxa, including the giant redwoods. All six species are predaceous and aquatic, living in debris and under stones in fast-running creeks. Because adults have a morphology suggestive of the terrestrial ground beetles, some researchers have proposed that Amphizoa represents an evolutionary transition between terrestrial and…