Pereskia horrida

Range and two subspecies

According to POWO, the species' natural range includes Peru and seasonally dry tropical habitats. Pereskia horrida subsp. horrida and P. horrida subsp. rauhii are accepted within the species. The database links Pereskia vargasii to the nominate subspecies, while former names containing rauhii require subspecies-rank information to be retained. [2-WWW]

Variation in stems, flowers and fruits

The monograph treating the species as Pereskia humboldtii describes shrubs to about 3 m or small trees to 6 m. Thin twigs may zigzag. Leaves are small, usually 1.5–4 cm long and 1–2.5 cm wide, with thick blades. Areoles produce spines and white hairs but do not renew foliage as typical short-shoot leaves. [Leuenberger 1986, Pereskia humboldtii description, 1986 treatment]

Flowers are small, usually 5–15 mm in diameter, solitary or grouped in small numbers. The broad species description gave colours from red and orange to white. This range must be retained separately from detailed subspecies identification. Thin-walled, juicy fruits turn black when ripe and are about 5–6 mm in diameter. Seeds are small, about 1.5–1.8 mm long. [Leuenberger 1986, Pereskia humboldtii description, 1986 treatment]

Spindle-shaped to almost spherical root thickenings were observed in cultivated specimens. Together, small leaves, small flowers and black fruits distinguish this species from larger pink-flowering members of the South American Pereskia group. The monograph ranges cover the historical broad treatment of P. humboldtii, rather than separate measurements of each present-day subspecies. [Leuenberger 1986, Pereskia humboldtii description, 1986 treatment]

Correction of the historical name

Pereskia humboldtii was the commonly used name of this plant for many years. Leuenberger discussed its replacement by Pereskia horrida under nomenclatural rules. Such correction does not mean discovery of a new species or a new cultivation method. Results in an older publication may still concern the same plant despite a different name. [Leuenberger 2008] [2-WWW]

Young twigs and flowering

Young shoots of the nominate subspecies were described with a green epidermis bearing stomata, fleshy pith and primary cortex, and long areolar hairs. Terminal and lateral flowers occurred on new twigs. Leuenberger also documented flowering older leafless branches. Observations concern the stem stages and subspecies described. [Leuenberger 2008]