Pilosocereus brevispinus


Pilosocereus brevispinus is a species of flowering plant in the cactus family Cactaceae, native to central Hispaniola, occurring in both the Dominican Republic and Haiti. It was first described in 2021, when it was separated from Pilosocereus polygonus. It has also been treated as a subspecies of Pilosocereus polygonus, P. polygonus subsp. brevispinus.

Description

Plants of Pilosocereus brevispinus have a tree-like habit, reaching in height when mature, with a woody trunk up to high and upright branches. The green or greyish green stems are across with 9–11 ribs. The areoles are about across and about apart. Flowering areoles have a dense tuft of white hairs long; non-flowering areoles have shorter hairs that may be lost with age. Both kinds of areole have 15–20 straight spines, generally long.
The flowers appear at night and have a smell described as "musty". Excluding the style, they are about long and about across. The white style is long. The outer perianth segments are rounded and fleshy, about long and wide. There are about 16 white inner perianth segments that are about long and wide. The fruit is spherical, about across, with red pulp and shiny black seeds.

Taxonomy

Pilosocereus brevispinus was first described in 2021. The specific epithet brevispinus refers to the shortness of the spines. Previously, all the species of Pilosocereus found on the island of Hispaniola were treated as Pilosocereus polygonus. P. brevispinus is distinguished from P. polygonus by generally having a smaller number of spines per areole that are distinctly shorter. It also has a longer tuft of hairs in flowering areoles than P. polygonus. P. brevispinus has also been considered not to be sufficiently different from P. polygonus to justify treating it as a distinct species, and hence accepted as a subspecies, P. polygonus subsp. brevispinus.

Distribution and habitat

Pilosocereus brevispinus is endemic to the island of Hispaniola. It is found in the centre of the island, in both Haiti and the Dominican Republic, at elevations of. Larger specimens are found in open habitats, smaller ones in forests.