Game InfoEditA large concentration of these aliens can be found in the Geonosian Caves on Yavin IV.
The Geonosian species can't be chosen as a vendor species.
Star Wars LoreEdit
In the distant past, Geonosis's largest moon was hit by a rogue comet, sending out a massive debris field that hammered the planet's surface into ruin, before settling into a ring of orbiting rock. This event killed off more than 99% of Geonosis's native species. Over millions of years, the few creatures who survived the devastation slowly reclaimed the planet. Random meteor impacts constantly weeded out the weaker species, leaving only the truly cunning, hardy, and ruthless species alive. The Geonosians, the dominant life form on the planet, constituted all three. A new form of transport, the cargo kite, was invented for use in the dense atmosphere of the planet by the early Geonosians. After the technical-minded Geonosians made contact with the galaxy, the Baktoid Armor Workshop moved several droid and weapon factories to the planet.
An insectoid species divided into castes, the Geonosians are native to the harsh rocky world of Geonosis. Geonosians construct immense, organic-looking spires within which reside their hive colonies. There are two main types of Geonosians: the wingless drones that mostly work as laborers, and the winged aristocrat, which includes royal warriors serving as scouts and providing security to the hive. All Geonosians have a hard, chitinous exoskeleton, elongated faces, multi-jointed limbs, and speak in a strange clicking language.
Though labeled "warriors," Geonosians do not have a standing military. They instead use their droid foundries to build armies for corporate interests wealthy enough to afford them—entities such as the Trade Federation and the Techno Union. Despite relatively simple minds, the Geonosians are adept at mechanical construction, and are contractors to many of the galaxy's biggest manufacturing concerns. They are responsible for the construction of some of the largest feats of engineering ever witnessed.
The hardships of the native environment coupled with rigid structure codified in their caste society has fostered a barbaric side to the Geonosians. Their simple minds view brutal violence as entertainment, and Geonosians congregate in massive execution arenas to watch victims doomed to die by being subjected to savage creatures.
In 24 BBY, during the reign of Archduke Poggle the Lesser, Geonosis became a member of the Confederacy of Independent Systems, which used the planet's factories to build its Droid Army. Two years later, in 22 BBY, Poggle scheduled a private meeting of the Confederacy leaders on Geonosis. It was expected that during this meeting the organizations that formed the backbone of the Separatist movement would put their resources at the disposal of Count Dooku, the Head of State of the Confederacy.
Unbeknownst to the Separatists, their plans of waging war against the Galactic Republic were heard by Jedi Knight Obi-Wan Kenobi, who had followed Jango Fett, a bounty hunter employed by Dooku, to Geonosis. Kenobi managed to transmit his discoveries to his Padawan Anakin Skywalker, who was at that time located on Tatooine , before being caught by the Separatists. After retransmitting the information to the Jedi Council, Skywalker and Padmé Amidala, the senator of Naboo, decided to rescue Kenobi, but ended up imprisoned themselves.
Eventually, Kenobi, Skywalker and Amidala were taken to the Geonosian execution arena, but managed to free themselves. The Separatists, in turn, introduced battle droids to the arena, triggering the Battle of Geonosis, the first battle of the Clone Wars, as Jedi reinforcements, led by Master Mace Windu, revealed themselves among the public and entered the arena to confront the droids.
After the Confederacy's defeat at the Battle of Geonosis, the planet was occupied by the Republic.
During the retaking of Geonosis, a temple was discovered where Queen Karina the Great of the Geonosians lived. She utilized a parasite, which enabled her to control the victim's mind.
Source: Star Wars Databank