Physiology and culture
Lurians were known to have multiple hearts, (DS9: "Through the Looking Glass") four lungs at the minimum, (DS9: "The Sound of Her Voice") and two stomachs. As a result, they were not only more resistant to damage than most species, but were also able to withstand poisons and other toxins much better. They were able to store liquids in their second stomach for many years if necessary.
The average Lurian was approximately the same height as the average Human (perhaps a few centimeters taller), but had a much broader and heavier body. Lurians were grayish- or tan-skinned beings descended from mammals. Their most noteworthy feature was their narrow, elongated heads. They had wide mouths, puggish noses, and small, deep-set eyes.