Hocotatian
Hocotatians are apparently the dominant race of the planet Hocotate. They are referred to as "Hocotatians" in The Ship's announcement of the Massive Receptacle Series. They are about the size of a nickel, and appear to be more advanced than humans, and having superior, or at least equal intelligence. They are capable of efficient extraterrestrial exploration and interaction, and use devices far beyond the current technology of humans. They bear multiple resemblances to humans, including expressing human-like emotions; physically, Hocotatians have a humanoid shape, the main difference being a larger head-to-body ratio.
Given the fact that oxygen is toxic to their species, it logically follows that their biochemistry is completely different. The chemical pathways followed by the respiratory system would have to be vastly different in order for oxygen to act as a toxin. A difference in chemistry of this magnitude most likely indicates that Hocotatians are unlike humans and all other life on Earth, in that they are not carbon based life forms.
Their primary means of communication is speech, and they are able to read and write. Hocotatians are a commercialized civilization, their currency being the Poko; commercial service and office exist in Hocotatian culture as well, with references to loan companies. The species has similar family structures to modern day western cultures: that is, husband, wife, children, and even pets.