Tenebran

Tenebrans (sometimes referred to as Tenebrites) are the sapient native inhabitants of the planet Tenebra, orbiting the giant star Altair.

When first contacted by Humans and Drommians, the Tenebrans were a primitive society, akin to the neolithic period of Earth's history.

Biology
The Tenebrans are large creatures of slightly conical shape, four pairs of limbs, and quill-like visual organs located near the crest of their heads. They breathe oxygen, but their metabolism is quite unlike that of Earth creatures. It is unclear whether they are carbon-based or not.

Appearances

 * Close to Critical, by Hal Clement (1958)