Manzanares (2000) placed this new species under P. devansayana; it differs by its long pedicels, 17 mm long (versus 10 mm long) and the obtuse apex of the sepals (versus acute).
P. brackeana is more closely related to P. dendroidea than to P. devansayana. It is distinguished from P. dendroidea by having spines in the lower portion of the margins of the subpetiole (versus entire margins). Its lanceolate floral bracts measure 7 mm long and have an attenuate recurved apex (versus 5 mm long, ovate floral bracts with an acute apex that is not recurved). The floral bracts are exceeded by the pedicels (versus slightly shorter), and the 17 mm long pedicel is much longer (versus 3 mm long). One of the most important characteristics is the pedicels that form a 90° angle with the rachis. During anthesis the erect flowers form a 90° angle with the pedicels. Both the sepals and petals are red, differing from P. dendroidea, which has red sepals at the base changing to yellow at the apex, and yellow petals.
The branches of P. brackeana are half fertile toward the tip and covered with flowers, the other half part is the stipe. The flowers of P. dendroidea occupy one third of the total length of the spike and the other two thirds is sterile (stipe).
P. brackeana can be confused with P. commixta. They differ by the almost total lack of spines at the base of the leaves in P. brackeana and by the 3-4 mm chestnut-brown spines totally covering the leaf margins of P. commixta.
While this new species is found in the Coastal region, P. lehmannii, with which it can be also associated, is found in the Amazon region. Another characteristic difference is that P. brackeana has a pedicel 17 mm long and that of P. lehmannii does not exceed 8 mm. —SeeManzanares 2005
