"The males of a species of deep-sea anglerfish are about 2 mm smaller, said University of Washington ichthyologist Theodore Pietsch, who described them in 2006. The males don't have stomachs and live as parasites on 1.8-inch (4.57-centimeter)-long females."
[We'll say it before someone else does: Guys would do that, wouldn't they?]
Louisiana State University herpetologist and environmental biologist Christopher Austinm, who discovered the little frogs, tells the AP "he knew about the anglerfish but felt that average species size [including males and females] made more sense for comparison."
As for the frogs, the BBC says finding them "was not an easy assignment. They are well camouflaged among leaves on the forest floor, and have evolved calls resembling those of insects, making them hard to spot."