Crystalloformicia

Crystalloformicia are various knightworms closely related to the arthrotheres, which are typically quadrupedal with their hind-most pair of legs modified into fins. They have articulated legs, fused gonopodia, tongue-like jaws, and crystal-shaped abdomens.

Order Crystalloformiciformes
Typical Crystalloformicians with articulated legs, fused gonopodia, tongue-like jaws, and crystal-shaped abdomens.