The squad returns to the UK to play Ireland at Gloucester on Tuesday 27 May and then the final game, the Gartmore Challenge against England at Twickenham on Sunday 1 June.
Thomas and Larkham are both new Barbarians and club president Micky Steele-Bodger is delighted to welcome them on board. He said, "Given the crowded international calendar these days we sometimes have to wait a while before inviting influential test stars to represent the club. It is a particular pleasure to have them with us this year and we are confident that they will enjoy the experience."
He added, "Like England and Ireland, we have had to cut our selection cloth in line with the European commitments of other clubs this weekend. However, we are delighted that players from Bath and Worcester, for instance, will be joining us in time for the second and third fixtures. Indeed, we are most appreciative of the co-operation we have received from a host of clubs across the board in making players available this year."
The Barbarians have also invited back three of the pack who shared in the famous win over South Africa six months ago - Justin Harrison, Federico Pucciarello and Mark Regan. Several other long-standing Barbarians return to the black and white shirt including Danny Grewcock who first played for the club a dozen years ago and fellow England World Cup member Andy Gomersall who has already played 12 times for the Baa-Baas.
The Barbarians have played Ireland on two previous occasions, winning the Peace International 70-38 in Dublin in 1996 and, four years later, winning 31-30.
It will be the eighth game against England at Twickenham with the Barbarians currently ahead 4-3 in the series.
Iain Balshaw (Gloucester & England), Peter Hewat (London Irish), Thinus Delport (Worcester Warriors & South Africa), Lesley Vainikolo (Gloucester & England), Gareth Thomas (Cardiff Blues & Wales), Morgan Turinui (Reds & Australia), Jaco Pretorius (Stormers & South Africa), Seilala Mapasua (London Irish & Samoa), Tyrone Smith (Brumbies), Stephen Larkham (Australia), Glen Jackson (Saracens), Andy Gomersall (Harlequins & England), Michael Claassens (Bath & South Africa), Ryan Powell (Worcester Warriors & Wales);
Federico Pucciarello (Munster & Italy), Cobus Visagie (Saracens & South Africa), Ollie le Roux (Leinster & South Africa), Patrice Collazo (Gloucester & France), Darren Crompton (Bristol & England), Mark Regan (Bristol & England), Sebastien Bruno (Sale Sharks & France), Justin Harrison (Ulster & Australia), Kris Chesney (Saracens), Ross Skeate (Stormers), Danny Grewcock (Bath & England), Pedrie Wannenburg (Blue Bulls & South Africa), Maama Molitika (Cardiff Blues & Tonga), David Croft (Reds & Australia), Mitchell Chapman (Brumbies), Craig Newby (Highlanders & New Zealand)
Coach: David Young
Tickets are still available for the match against Ireland at Kingsholm on May 27th (7.45pm KO). Tickets can be purchased online at www.gloucesterrugby.co.uk or by calling the ticket hotline on 0871 871 8781 option 2.
The ticket office will be open the following hour: Sunday 25th 8.00am until 1.00pm, Monday 26th 9.00am until 5.00pm and Tuesday 8.30am until 7.45pm.