Habit and roots
The plant usually branches at the base. Stems are jointed, erect or recurved, generally 0.7–1.5 m long and occasionally reaching 2 m. They measure 2–3 cm across. The original description calls the stems monomorphic. This denotes retention of a similar overall structural pattern in the material examined, in contrast to the conspicuous transition from juvenile stems to cylindrical adult portions in some other Acanthocereus. [House et al. 2013]
The main root develops a thickened region up to 36 cm long and 6 cm in diameter, bearing numerous fibrous roots. An enlarged underground system therefore accompanies relatively slender aerial growth. The protologue also documents a plant maintained in a botanical garden, whose flower was used to prepare the type material. [House et al. 2013]
Areoles and spines
The areoles, shortened shoots that produce structures including spines, are hemispherical and covered with white or beige wool. Their spacing of 1–2 cm gives the stem a densely armed appearance. Each areole usually produces 10–13 rigid spines, occasionally up to 15. These are 5–15 mm long, swollen at the base and directed outwards at different angles. Young spines are red at the base and pale towards the tip, becoming grey with age. [House et al. 2013]
Flowers and opening time
The flower reaches approximately 10 cm in length. Its long, narrow tube opens into a spreading perianth, with a distinct nectar chamber near the base. Both outer and inner tepals are deep pink, and numerous stamens and the stigma project from the flower. Flowering was observed in March and April. The opening period from before dawn until before midday was recorded from the plants described. [House et al. 2013]
The authors associated this combination of colour, form and opening time with possible hummingbird pollination. This is a hypothesis based on floral traits. Acanthocereus lempirensis also has pink flowers, but they open at night and their tepals have differently shaped tips. The combination of floral shape and flowering rhythm helps distinguish these two pink-flowered Honduran species. [House et al. 2013] [Vega et al. 2023]
Habitat and naming history
Known sites lie in dry forests near Tegucigalpa at 800–1000 m elevation. The description reports regional mean annual rainfall of 851 mm and seasonally deciduous woody vegetation. In 2013, the authors knew six wild individuals in a fragmented forest landscape threatened by urban expansion. This supported their suggestion that the species might qualify as Critically Endangered. The number describes knowledge at the time of the protologue. [House et al. 2013]
The species was described as Peniocereus canoensis. Arias and Korotkova published the combination Acanthocereus canoensis in 2017, and POWO accepts it. The transfer accompanied a broader revision of generic limits. This particular species was outside that study’s molecular sampling, so its inclusion relied on morphological comparison. [Korotkova et al. 2017] [2-WWW]
The epithet canoensis refers to the Canoa River. Descriptive material came from two nearby sites in the department of Francisco Morazán. Retaining this information links the name to the origin of the first documented plants and makes their identification history traceable. [House et al. 2013]
Related articles
Synonyms and names in the literature
Peniocereus canoensis [2-WWW]