Ilex cassine is a holly native to the southeastern coast of North America, in the United States from Virginia to southeast Texas, in Mexico in Veracruz, and in the Caribbean on the Bahamas, Cuba, and Puerto Rico. It is commonly known as dahoon holly or cassena, the latter derived from the Timucua name for I. vomitoria.
It is a large shrub or small tree growing to 10–13 m tall. The leaves are evergreen, 6–15 cm long and 2–4 cm broad, glossy dark green, entire or with a few small spines near the apex of the leaf. The flowers are white, with a four-lobed corolla. The fruit is a red drupe, 5–6 mm in diameter, containing four seeds. As with other hollies, it is dioecious with separate male and female plants. Only the females have berries, and a male pollenizer must be within range for bees to pollinate them.