The team of four riders from across Britain were interviewed remotely by a panel of three selectors including Pony Club CEO Marcus Capel.
They were selected on results, commitment to pony club activities and teamwork.
They also had to have attained at least their B Test.
The quartet will fly out as a team to Atlanta, Georgia and will be given horses to ride while they are there.
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Duncan has been an active member of Lauderdale Hunt Pony Club for many years and has competed on numerous teams including showjumping, eventing, dressage, mounted games, quiz and Horse and Pony Care.
District Commissioner of Lauderdale Hunt Pony Club Alex Mundell is delighted that Duncan has been selected for this prestigious team.
She said: “Over recent years Duncan has increased his responsibilities within our branch, taking on the role of coach and mentor to young members.
“He has fulfilled this role extremely well and is highly regarded by all.”
This is the second time Lauderdale Hunt Pony Club has had a member selected for this team – Charlotte Dun, a well known local point to point rider, described her experience as “the best thing I have ever done”!
Duncan’s mum Gillian said: “I think Charlotte and my son are the only two from Scotland that have ever been picked for this.
“If it goes ahead in November then Duncan and the rest of the team (all aged between 18 and 25) will be away for a fortnight and I think they’ll be competing in six or seven events.
“But I don’t think it will happen to be honest (due to coronavirus).
“They are making a decision at the end of July whether it happens this year or next year. It would be nice to know one way or the other.”
Duncan is currently working and gaining experience in Galway in Southern Ireland for showjumper Keith Clogher.
Due to Covid 19 restrictions they are not out competing at the moment but are spending their time breaking and bringing on talented ponies and horses for the future.