LONDON, United Kingdom — UK online fashion seller Boohoo Group Plc named a new chief executive from the fast-growing Primark chain, offering him a payout of as much as £50 million ($65 million) to spur growth.

John Lyttle, currently chief operating officer of Primark, will join Boohoo in March, according to a statement Monday. The move comes as Boohoo, which owns the PrettyLittleThing and Nasty Gal labels, bucks the UK’s general retail gloom with a fast-fashion business aimed at trendy young shoppers who’re snapping up items like its 8-pound animal-print bodysuits.

Despite eschewing online sales, Primark — owned by Associated British Foods Plc — has been another British retail standout. It’s added 15 new stores this year, bringing the total to 360, and plans to add a further 14 next year. Sales were dented by an unusually hot summer, the chain said earlier this month.

Lyttle’s pay will be closely linked to gains in the company’s market value. He’ll receive a base salary of £615,000, with a bonus of up to 150 percent of annual pay. The new chief executive can receive a payout of as much as £50 million if the company’s value rises 180 percent, to £5.6 billion, over five years. Growth of less than 60 percent would yield nothing.

Boohoo’s sales have risen 24-fold since 2011, to about £580 million for the year ended in February. The shares have fallen almost 9 percent this year, though they were up as much as 3 percent early Monday in London.

One of the current joint chief executives, Mahmud Kamani, will become executive chairman, focusing on long-term strategy and stepping away from day-to-day operations. The other, Carol Kane, will assume the title of group co-founder and executive director, “overseeing the development of the product proposition,” the company said.

By Eric Pfanner; Editors: Kenneth Wong, John J. Edwards III, John Lauerman.