Titanus Mosura is a prehistoric super-species of moth-like Titans from the same era and ecosystem as Godzilla. Though smaller than most Titans, the species evolved several adaptations that allowed them to survive in the deadly ancient ecosystem as the other Titans. These adaptations include mantis-like forelimbs, sharp vertical mandibles, and bio-luminescent behavior. Members of the species appear to mature astoundingly fast, as newly hatched larva can pupate almost directly after hatching. Most notably, the species shared a warm, symbiotic relationship with that of Godzilla's.
One member of the species, dubbed Mothra, hatched from her egg in 2019 after being monitored by Monarch for several years. After pupating behind a waterfall not far from where she hatched, Mothra joined Godzilla in his fight to defeat Ghidorah and save the planet. She ultimately dies in the process of defending Godzilla while he was weakened, but the ashes from her body allowed Godzilla to enter his burning form and defeat Ghidorah once and for all.
A news headline reveals that Mothra had laid an egg sometime before her death, ensuring the species' survival.