Nepeta is a genus of about 250 species of flowering plants in the family Lamiaceae. The members of this group are known as catnips or catmints due to its famed liking by cats—nepeta pleasantly stimulates cats' pheromonic receptor. The genus is native to Europe, Asia, and Africa, with the highest species diversity in the Mediterranean region east to mainland China. It is now common in North America as a weed. Most of the species are herbaceous perennial plants, but some are annuals. They have sturdy stems with opposite heart-shaped, green to grayish-green leaves. The flowers are white, blue, pink, or lilac and occur in several clusters toward the tip of the stems. The flowers are tubular shaped and are spotted with tiny purple dots. The scent of the plant has a stimulating effect on cats. Also, it is claimed by some that the oil isolated from catnip by steam distillation is a repellant against insects. Research has shown this to be not the case with the yellow fever mosquito.