Pilosocereus alensis

{{Short description|Species of cactus}}

{{Speciesbox

| taxon = Pilosocereus alensis

| authority = (F.A.C.Weber ex Rol.-Goss.) Byles & G.D.Rowley

| synonyms = {{specieslist

|Cephalocereus alensis| (F.A.C.Weber) Britton & Rose

|Cephalocereus guerreronis| (Backeb.) Buxb.

|Cereus alensis| (Weber) Vaupel

|Pilocereus alensis| F.A.C.Weber ex Rol.-Goss.

|Pilocereus guerreronis| Backeb.

|Pilosocereus guerreronis| (Backeb.) Byles & G.D.Rowley

}}

}}

Pilosocereus alensis, the Sonoran old man cactus, is a species of cactus native to Western Mexico, from Sonora south to Jalisco.{{cite web|title=Pilosocereus alensis (F.A.C.Weber ex Rol.-Goss.) Byles & G.D.Rowley|url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:196661-2|website=Plants of the World Online}} The hairs protect the flower buds. Flowers open at night in June and give off the odor of ammonia, attracting bats for pollination. The juicy fruit is tasty.{{Cite web|title=Alamos Succs; Pilosocereus alensis|url=https://www.desertmuseum.org/programs/alamos_succs_pilale.php|access-date=2021-09-29|website=www.desertmuseum.org}}