The Attendant was one of the two guardians of the Galactic Seed Vault and the only of the two who knew about the secret thirteenth vault containing the Genesis Seed. It was engineered by the creators of the Vault to be part of the vault's ecosystem.
It was beetle-like and had mandibles on either side of the head. Its forelegs were multi-segmented, some ending with claws. It had a proboscis where humans and Time Lords have a nose. It also had mandibles.
The Attendant was not capable of audible speech. It usually communicated by chittering noises and gestures. However, in urgent situations it could also communicate telepathically. (PROSE: The Secret in Vault 13)