DA parliamentary leader John Steenhuisen appointed Natasha Mazzone as his chief whip at the party's caucus meeting on Thursday morning.
A week ago, the DA was without a chief whip, as Steenhuisen had to vacate this position because his term was tied to that of Mmusi Maimane, who resigned as DA leader and subsequently as its parliamentary leader.
Steenhuisen was elected unopposed as parliamentary leader and has since indicated that he will contest for the party leadership.
"Having served with distinction as a Member of Parliament for the past decade, Natasha brings an ideal balance of knowledge, grit and levelheadedness to this crucial position," Steenhuisen said in a statement.
As the DA's spokesperson on public enterprises, Steenhuisen said Mazzone had "worked tirelessly to strengthen our democracy by leading the charge against the pervasive corruption and maladministration in our state-owned enterprises (SOEs)".
"I look forward to working alongside Natasha as we strive to build a stronger opposition that will vigorously hold the executive accountable, while offering real policy and legislative alternatives to get South Africa working again."
Jacques Julius will remain as deputy chief whip – a position to which he was elected in May when the 6th Parliament was established. He acted as chief whip while the party was without one.
Steenhuisen also appointed Solly Malatsi as his parliamentary counsellor.
While addressing the Cape Town Press Club on Monday, where he announced that he would contest the party leadership, Steenhuisen praised Malatsi for his professionalism as the party's spokesperson.
"I am confident that this talented and diverse team has what it takes to spearhead our fight for the interests of all South Africans and, in particular, those left behind by the failing ANC government.
"As the official opposition in Parliament, we are ready to roll up our sleeves and hit the ground running as we strive to build a prosperous South Africa that works for all. The DA will fight for an enterprise economy that provides real opportunities, a world class basic education system and a modern, non-racial society governed by the rule of law."
Mazzone, a former leader of the DP Youth Branch, was elected as a councillor in Pretoria at the age of 21. She later became the party's chief whip in the council and held this position until she was elected to the National Assembly in 2009.
She is also one of the deputy federal council chairpersons.
Julius was elected to the National Council of Provinces in 2014.
Malatsi worked as a spokesperson for former Western Cape MEC for transport and public works, Robin Carlisle, and then-mayor of Cape Town Patricia de Lille, before being elected to the National Assembly in 2014.