In New Zealand, Pteris pacifica has an erect or short-creeping, scaly rhizome; rhizome scales narrowly ovate, with dark centres and pale erose margins. Fronds 200–760 mm long. Stipes yellow-brown to chestnut-brown, 160–310 mm long; rachises not winged. Laminae mostly 1‑pinnate-pinnatifid but 1-pinnate-bipinnatifid at base and abruptly narrowed to a pinnatifid terminal segment, ovate or elliptic, 210–460 mm long, 80–200 mm wide. Primary pinnae in 5–6 pairs; longest primary pinnae 60–200 mm long, stalked, divided almost to the midrib into secondary segments of ± uniform length, shortening only towards the apices; adaxial surface with spine-like growths on the costae; basal primary pinnae with 1–2 elongated pinnatifid segments up to 100 mm long on the basiscopic side; ultimate segments up to 15 mm long and 3 mm wide, margins entire, apices obtuse. Veins free. Sori continuous along sides of ultimate segments.
Recorded as occurring spontaneously in urban gardens.
Heenan et al. (2002). Voucher AK 205931, 1991.