Genus supposed older than Cereus, hence the name (prae = before).
A genus of shrubby plants, with slender cylindrical stems, more or less erect to prostrate, without mucilage, strongly branched at the base, except when the apex has been damaged. Areoles rounded, situated on a prominence, spines aciculate.
Flowers nocturnal, self-sterile, funnel-shaped, with a curved, naked, sturdy, thick-walled floral tube, white to greenishyellow, slightly perfumed, pollinated by bats (Glossophaga longirostris) and Sphingideae. Fruits globose to egg-shaped, naked, fleshy, red with white juicy pulp, laterally dehiscent, floral remains persistent. Seeds black, shiny, elongated and ruminate to tuberculate. Dispersal of seeds probably ensured in some regions by the tapir (Tapirus terrestris).
The genus Praecereus grows in the shade of tropical dry forests, cerrados (dense tropical savannas), around trees and shrubs, among rocks, on loamy soils, sometimes on sloping ground, from sea level up to 2000 m in altitude. Rainfall can reach 1000 mm / year and the temperature is high all year long.
Argentina (Misiones), Bolivia (Beni, La Paz, Santa Cruz), Brazil (Mato Grosso do Sul, Parana, Sao Paulo), Colombia, Ecuador (Loja), Paraguay (Manabi), Peru (Amazonas, Cajamarca, Lambayeque, Piura, San Martin, Tumbes), Trinidad, Venezuela (Vargas).
Currently one species + 4 subspecies:
– Praecereus euchlorus* Weber (Taylor) 1997
– Praecereus euchlorus subsp. amazonicus (K.Schum.) N.P.Taylor 1997
– Praecereus euchlorus subsp. diffusus (Britton & Rose) N.P.Taylor 1997
– Praecereus euchlorus subsp. jaenensis (Rauh & Backeberg) Ostolaza 1998
– Praecereus euchlorus subsp. smithianus (Britton & Rose) N.P.Taylor 1997
References: "TAXONOMY of the CACTACEAE" - ISBN 978-84-617-3692-8 (Vol. 2)