The Selenites are a race of sapient, hive-minded insectoid aliens that live in the interior of Earth's Moon and are named after Selene, the Goddess of the Moon in Greek Mythology. They appear physically similar to ants and - much like ants - are divided into castes; existing in a myriad of different physical forms to serve a variety of purposes in their technologically sophisticated society, with each Selenite specialising in one particular area. However, due to the weaker gravity of the moon, the Selenites have more fragile and flimsy bodies that can be easily damaged by stronger species such as humans. They are also omnivorous - eating both meat (such as the "Mooncalves") and fungi.
The Selenites live underground in passageways and cities - complete with water channels and with lighting provided by bio-luminescent plankton, with some Selenites in the deeper cities developing bio-luminescence themselves due to consuming the plankton. Much like species on Earth, there are male and female Selenites. However, there are also Selenites who possess no sex. All of Selenite society is unified across the moon and is ruled by a single monarch referred to as "The Grand Lunar".
The Selenites appeared in the book The First Men in the Moon by H.G. Wells, set in 1901 and in which a pair of men - a scientist named Mr Cavor and a businessman named Mr Bedford - construct a sphere that can fly thanks to a new substance created by Mr Cavor called "Cavorite", which can be used to defy gravity. Using this, the two men journey inside the sphere to the moon; encountering the Selenites for the first time. The first meeting ended up descending into conflict due to fear and lack of communication between the two species, with Bedford escaping back to Earth in the Sphere while Cavor is injured and ends up remaining on the moon. Cavor did manage to learn more about the Selenite's society and even taught two Selenites how to speak English, but the Selenites would eventually stop his attempted communications with Earth after Cavor revealed humanity's propensity for war - with Cavor's fate ultimately unknown after his attempts to send the process for making Cavorite ended abruptly. Cavor described the Selenites as been above humanity not only in intelligence, but also in their social structure and morality.
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