Taylor thrashed 74 from 51 balls, including 11 boundaries, as the tourists recovered from 41 for three.
The wicketkeeper-batter and Anya Shrubsole also took 18 from Shabnim Ismail’s final over to boost England’s total.
— England Cricket (@englandcricket) February 18, 2016
Skipper Charlotte Edwards, back at the top of the order after moving to number three in the ODIs, Tammy Beaumont and Amy Jones all fell cheaply.
Heather Knight added 18 from 11 balls but she and Danni Wyatt fell in quick succession as the tourists limped to 81 for five.
Georgia Elwiss offered Taylor some much-needed support with 18, and although Jenny Gunn made only two, Shrubsole ensured there was a late wag in the tail with 10 off four balls.
Moseline Daniels and Dane van Niekerk were the pick of the South Africa bowlers with two wickets each.