The Yattho are a species of hairy bipedal humanoids that were inhabitants of the planet Rigel X.
The Yattho's natural habitat was the dense forests of the planet Rigel X (though one source does contend that they were immigrants to this planet). Rigel X is covered with massive wroshyr trees, in which the Yattho constructed their homes and cities. Reportedly, the Yattho were descended from tree-climbing mammals.
They had the ability to easily learn most languages. However, the Yattho lack the vocal structure to speak anything other than their own languages.
Adult Yattho are tall, in excess of two meters in height, and were covered with a uniform, mid-length coat of thick hair in various shades of brown. Although albino Yattho are rare, they were not unheard of. However, such a birth was generally held to be a bad omen, as white hair did not blend in with the earth-tones of their forest surroundings.
Young Yattho (pups) were large at birth (averaging slightly less than one meter). Yattho possess vicious-looking retractable claws for climbing. Female Yattho have six breasts and gave birth to live-born young, with their gestation period nearly a year long. After birth, a Yattho grew very fast, fully conscious and able to walk unassisted within one standard year. The average lifespan of Yatthos' was around 600 years. In spite of their bestial appearance, Yatthos' were highly intelligent and had mastered advanced technology, including hyperspace travel. The Yattho also possessexceptional skill in mechanical repair. An old saying was "Give a Yattho a knife and send him into a forest in the morning, and by evening he would have carved you a table to eat dinner on - and a house to put it in."
The Yattho are often short-tempered.