The specific name of the type species, P. minchami, honors Mr. H. Mincham, the private collector, who in 1957 had collected and presented a number of fine specimens of Ediacaran fossils to the South Australian Museum.

[1] This species is also known from deposits of the Verkhovka, Zimnegory and Yorga Formations in the White Sea area of the Arkhangelsk Region, Russia.

[3] P. sagitta is found in the Verkhovka formation on the Solza River, White Sea area of the Arkhangelsk Region, Russia.

[2] Furthermore, the strong resemblance of P. sagitta to the primitive mollusk-like bilateran Temnoxa[4] and similarities to parts of Kimberella[7] casts further doubt on an arthropod affinity.

[9] They are suggested to have been mobile and able to actively orientate their bodies towards the current direction, with smaller individuals from the Ediacara biota in Australia often found in close association with each other.