There is much less known about the lifestyle of assassins of yesteryear, of which only about 50 species have been excavated in fossil form. The newcomer in the group, named Aphelicophontes danjuddi, is one of the intact so far.
The fossil was first cut from a cliff in Colorado’s Green River Formation, a treasure trove of fossil fish and insects. The extraction process divided the fossil into two mirror images, each extending the length of the bug, which ended up in the hands of different fossil collectors. One of them, Yinan Wang, met Sam Heads, Mr. Swanson’s adviser to the University of Illinois, contacted on an idea that it was ‘new to science and paper-worthy’. This was – that’s why Mr. Wang donated the fossil to the team’s cause. Dan Judd, the owner of the fossil of the piece, soon followed and gave the species’ name to the insect.
After the fossil halves were reunited, the researchers began the difficult task of placing the bug in its pedigree. The impeccable quality of the fossil seems to have greatly facilitated this process, says Mercedes Burns, an evolutionary biologist at the University of Maryland, Baltimore County, who was not involved in the study.
The genital capsule, or pygophore, is particularly well preserved, a calyx-like shield covering the fragile phallus and other shaky reproductive ornamentation until it is time for copulation. It is a hard shell that protects the penis, said Mr. Swanson said, not unlike the exoskeletal structures that break into the rest of the bug’s body.
The remains of the dwarf ear were burst in two when the fossil tore for the first time. But careful examination of the two prints showed that the contents of the capsule persisted. Among them was the basal plate of the insect, a structured structure and tips of the sac-like fallotheca, which support the penis. In live assassins, the whole package does not look like a Darth Vader mask or a translucent athletics cup.