Spinner Bruce Martin proved the most adept of Auckland's bowlers with two for 21 from four overs.
Auckland were never in the hunt, after a slow start, finishing on 151 for nine.
Anaru Kitchen top scored with 42 off 39 balls, and captain Gareth Hopkins' lively 31 off 19 briefly putting impetus into the chase.
Styris rounded off his day with two wickets in six balls to undermine any potential middle order revival.
Otago were too good for Wellington in Dunedin, hitting 204 for three, led by Hamish Rutherford's rollicking 79 off 44 balls, to take top spot from the visitors.
Auckland and ND meet again in Hamilton tomorrow, while Canterbury hosts Wellington. Auckland must win to stay in the frame.
Points: Otago 24 (9 games), Wellington 20 (9), ND 20 (8), Auckland 16 (8), Canterbury 16 (8), CD 4 (8).