Christiansen, who won three Olympic titles at London 2012 having claimed double gold at Beijing 2008, is joined on the seven-strong list by fellow British Para-dressage rider and Rio 2016 hopeful Erin Orford.

It also features young people and families that are keen to be active and help raise funds for charity, including 11-year-old Sofia Crockatt, who competes at her local athletics club despite losing her leg through Meningococcal disease at the age of two.

Ten-year-old twins Seb and Ben Goold, and father and daughter Stephan and Chloe Couture, aged 51 and nine respectively, complete the list.

Seb Goold had an accident in 2014 which left him with a brain injury and leg amputation from the knee.

Chloe Couture has Cerebral Palsy and is visually impaired.

All the ambassadors participated in Tribal Series' inaugural Para Tri event last August, when 300 participants, many of whom had never entered a competitive sporting event before, descended on Dorney Lake in Windsor to take on solo Para-triathlons and relay challenges.

They did so alongside existing Tribal Series ambassador David Weir, Britain’s six-time Paralympic gold medal-winning wheelchair racer who has supported the series since its inception last year. 

"I was fortunate that I found a sport I loved and excelled in at a very young age, but I know that isn’t the case for many disabled people," said Christiansen, who was born with quadriplegic cerebral palsy.

"The accessibility of Tribal Series means that absolutely everyone, regardless of disability, has the opportunity to have fun and complete a sporting challenge with as little or as much support as they need.

"I am proud to be an ambassador of this unique series."

In November, Para Tri won gold and bronze in the respective "Sporting Event 2015" and "Outdoor Event 2015" categories at the Event and Visual Communication Association LIVE Awards in London. 

"It’s amazing that there is now a sports series that prioritises our needs and wishes," said Stephan Couture. 

"Chloe uses a wheelchair to get around and we had never contemplated this kind of racing before.

"Para Tri gave us the confidence to go on and do other triathlons and sporting events, and this year we are competing at all of the Tribal Series events.

"It’s fantastic that there are no limitations on participants and the focus is on achievement.

"We are thrilled to be ambassadors and encourage more families with disabled members to give it a go."

Tribal Series is the creation of international events agency Sportsworld and British Paralympic track and field athlete Sophia Warner. 

There will be two Para Tris this year, coinciding with the debut of triathlon as a Paralympic sport at Rio 2016. 

Para Tri South is scheduled to take place in Dorney Lake on August 7, following Para Tri North in Crosby Lakeside, Liverpool on July 24.

There is also set to be two new events, Para Swim and Para Run/Push, in Dorney Lake on May 15.