Lemaireocereus

The genus contains tree-like cacti characterized by columnar stems that branch from the base. They have thin ribs, round whitish areoles, and short, stiff, bulbous spines at the base. The flowers appear near the apex of the plant and feature lanceolate or apiculate petals. The petals are ivory white or orange-yellow with fleshy pink to carmine red colors and possess leathery, fleshy bracts in the pericarpel. The receptacle tube bears hairs and trichomes. Outer tepals are papery and greenish-brown. The flowers are pollinated by bats, including Choeronycteris mexicana, Leptonycteris curasoae, and Leptonycteris nivalis.:^[2]

The genus Lemaireocereus was first published in 1909 by Britton and Rose in Contributions from the United States National Herbarium. Many other species from the genera Armatocereus, Cephalocereus, Stenocereus, Isolatocereus, Marshallocereus, and Lophocereus were included in this genus. At one point, the entire genus was dissolved, but these two species remain.^[3] The genus is named in honor of the French botanist and cactus specialist Charles Lemaire.^[4]

As of February 2025^[update], Plants of the World Online accepted two species:^[5]

Image	Scientific name	Distribution
	Lemaireocereus hollianus (F.A.C.Weber ex J.M.Coult.) Britton & Rose 1909	Mexico (Michoacán)
	Lemaireocereus lepidanthus [de] (Eichlam) S.Arias & Terrazas 2009	Mexico (Guerrero, Oaxaca, Puebla)