For those less knowledgeable of Star Wars species (alphabetical order, pasted from other websites):
Chiss (Tejanna):
The Chiss were a blue-skinned, humanoid sentient species that possessed red eyes and dark blue hair.
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Gank (Hawke):
The Ganks were a sentient humanoid species of fur-covered carnivores. The typical member of the species had a face that was squared-off and yellow in color, the expression trapped in a perpetual snarl that non-Ganks found unattractive. Small, mean-looking eyes peered from above the maw, and ears facilitated the sense of hearing. The head sat atop a thick neck, which emerged from between broad, strong shoulders. These capped two thickset, powerful arms, which terminated in hands with five fingers each. In contrast, their legs were relatively short; over all, the average member of the species stood 1.6 meters (4.5 feet) tall. Their heavy build afforded Ganks great strength, yet they were also spry runners. They augmented their bodies with cybernetics, making them a species of cyborgs. These implants allowed Ganks to engage in silent communication with their fellows.
Good luck finding any real variety of Gank images, there aren't many.
Trandoshan (Tashal):
Trandoshans were sentient humanoids with smooth, scaly skin. Trandoshans ranged from being tall and fairly gaunt, to being short and more rotund. Trandoshans were powerful beings, and had long thin arms that ended in either three thick digits, or four thin digits, including a thumb. Trandoshans had a pair of eyes set back on a pointed skull, and a maw filled with pointed teeth. Trandoshans often walked barefooted, and had feet with three digits each. A Trandoshan's skin color could vary wildly, and Trandoshans could be found with green, red, orange, brown, or yellow skin. Some Trandoshans, such as one named Smug, had brownish-orange skin with red stripes on his face.
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Twi'lek (Lissewa):
Twi'leks were a species of tall humanoids whose skin spanned a vast array of colors, including white, orange, yellow, green, pink, blue, purple, and red. Their most distinctive feature was the pair of prehensile tentacles that sprouted from the base of their skulls, known as lekku, or headtails. Although Twi'leks normally had two of those tentacles, some individuals had four of them.
The species had two sexes, male and female. While males had ears with lobes resembling that of humans, females had cone-shaped hearing organs.
Twi'leks were usually thin, although corpulent individuals were known to exist. Under normal circumstances, they had a higher body temperature than other humanoid species
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