(Updates to close)
Feb 23 (Reuters) - Australian shares ended lower on Thursday, heavily pulled down by the materials sector, with Rio Tinto slumping after trading ex-dividend.
The S&P/ASX 200 index was off 0.4 percent, or 20.399 points, at 5,784.7 by the close of trade. The benchmark ended 0.2 percent up in the previous session.
The S&P/ASX 200 materials index fell nearly 2 percent, with shares of Rio Tinto, the world's second-largest miner, facing their biggest fall in eight months.
BHP Billiton Ltd slid 2.7 percent, its second straight day of losses, as copper prices drifted lower.
London copper prices slipped on Thursday, with the U.S. dollar firming as the market reassessed minutes from the Federal Reserve's last policy meeting that kept the prospect of a March rate hike in play.
South32 Ltd fell 3.9 percent while Fortescue Metals Group Ltd dropped to a more than one-week low.
The worst performer on the main index, however, was Ardent Leisure Group plunging to a more than three-year low after it posted a half-year net loss of A$49.4 million, hurt by sales of health clubs as well as a ride accident at its Dreamworld theme park in October.
New Zealand's benchmark S&P/NZX 50 index closed 0.4 percent higher, or 27.04 points, to finish the session at 7,089.52.
Healthcare, industrial and material stocks led the gains with Fisher & Paykel Healthcare Corp and Fletcher Building Ltd rising 1.7 percent and 1.2 percent, respectively.
Air New Zealand Ltd hit more than a five-week high after it reported first-half profit decline but provided a bright outlook that it expects a reduction in flights by Chinese competitors. ($1 = 1.3016 Australian dollars) (Reporting by Christina Martin; Editing by Jacqueline Wong)