Segment and lateral flower
Segments are globose to obovoid, light brown or grey. The surface is tuberculate, areoles lack dense wool, and cylindrical central spines measure about 1–2 mm in the species comparison. [Las Peñas and Bernardello 2021, Table 2]
The flower develops on the side of the segment. The same position category was recorded for P. reticulatus, while the other species in the table had terminal flowers. Flower position is a trait of growth architecture, separate from perianth colour or spine form. [Las Peñas and Bernardello 2021]
Range and evolutionary lineage
The species is associated with Argentina's Neuquén province. Analysis of three chloroplast regions placed it as an early-diverging lineage in the group containing P. araucanus and P. hickenii. The distinct molecular result occurs alongside distinguishing habit traits. [Las Peñas and Bernardello 2021]
The cytogenetic material had a count of 2n = 99. At the basic number x = 11, this corresponds to nine chromosome sets. No separate DNA content result was given for this material, so the record contains no calculated genome mass. [Las Peñas and Bernardello 2021, Table 1]