Autor: Britton & Rose

Genus honouring Antonio Pacheco Leao (1872-1931), director of the Botanical Garden of Rio de Janeiro, Brazil (see portrait above with Albert Einstein, ccourtesy of Botanical Garden of Rio de Janeiro, Brazil).
A genus of erect or spreading shrubby plants, rarely branched, with slender, woody cylindrical stems, without mucilage, with areoles very close-set. Ribs low and rounded; central and radial spines not differentiated, short, finely aciculate.
Flowers nocturnal, self-sterile, subapical, tubular, white, floral remains persistent, pollinated by bats. Fruits globose to egg-shaped, red, indehiscent, with deciduous spines. Seeds black, shiny, with intercellular dimples.
The monotypic genus Leocereus grows in the Brazilian caatinga, especially in a type of arborescent savanna (campo cerrado), also in the campo rupestre (in Brazil, mountainous subtropical savanna), on sandstone cliffs, from sea level up to 1200 m in altitude, often in a dense spiny-shrub vegetation, together with other Cactaceae (Meiocactus, Pilosocereus).
Brazil (Bahia, Minas Gerais, Piaui).

Currently 2 recognised species:
– Leocereus bahiensis* Britton & Rose 1920
– Leocereus estevesii P.J. Braun 1990

References: "TAXONOMY of the CACTACEAE" -  ISBN 978-84-617-3723-9 (Vol. 1)