Leaves broader, narrowly oblong to linear, 5-30 cm by 8-12 mm, abruptly acuminate, caudate (the tail 1-3 cm long), the base narrowed into a 1-5 cm long petiole, the margins smooth almost throughout, scabrous only at the very top just below the aculeate-scabrous tail. Inflorescence consisting of a single spikelet, 5-8 by 4-5 mm.
Asia-Tropical: New Guinea present, Fly R present, Idenburg R present, Otakwa R present, Palmer R present, Papua present, Ramoi present, Vogelkop present, W. New Guinea present
Malesia: New Guinea (W. New Guinea: Ramoi, Vogelkop, Otakwa R., Idenburg R.; Papua: Fly R., Palmer R.).
However different in habit tall specimens of P. longirostris with narrowly linear leaves very gradually narrowing towards the apex, may be from dwarf specimens of P. simplex with oblong, petiolate and caudate leaves, it is questionable whether they are specifically distinct. Provisionally they are kept apart because the difference in facies seems to correlate with one in the shape of the upper hypogynous scales, and there is also a marked difference in the scabridity of the leaf-margins. On the other hand I fail to find any essential difference in the nuts. Whether the characters indicated above hold true, can only be decided when the variability of both species will better be known.