Arachnosaur

The arachnosaur is an alien from the IDW portion of the Generation 1 continuity family.

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The arachnosaur is a large spider-like creature native to the planet LV-117. It dwells in the more arid regions of the planet, and buries itself in the sand in order to ambush its prey. Springing out of the sand, it is a fearsome sight, with its eight massive legs and giant fangs, but if it is met with resistance it will flee.

Fiction

IDW comics continuity

Wheelie was ambushed by an arachnosaur in the deserts of LV-117. The beast inadvertently bit into his energon convertor, shocking it with a jolt of energon. The arachnosaur fled without devouring Wheelie, but he was forced to make repairs to his convertor. Spotlight: Wheelie