Lynn, who was appointed as Wales head coach in January, has named a squad based around the 15 Welsh internationals who featured in the Women’s Premier Rugby semi-finals.
The Wales head coach’s own Gloucester-Hartpury, Bristol Bears, Harlequins and Saracens were the sides in the final four of the league widely regarded as the best in the world.
Lynn’s Gloucester-Hartpury will face Saracens in the final with the Bears and Quins Wales Test stars meeting up for the Wales W6N this week.
Wales captain Hannah Jones will lead the squad, with Keira Bevan and Alex Callender appointed as vice-captains in a new leadership team for the squad.
Lynn has recognised the impact of the new cross-border league, the Celtic Challenge, with players from the Welsh sides, Gwalia Lightning and Brython Thunder, named in the squad.
Gwalia have won five of their seven games and sit third in the league table, with the likes of skipper Bryonie King, No 8 Gwennan Hopkins, lock Alaw Pyrs, prop Maisie Davies and scrum-half Sian Jones.
While Brython have been captained by Wales second row Natalia John, with the likes of fellow Welsh international Hannah Bluck and featuring the rising talents of flanker Lucy Isaac and prop Cadi-Lois Davies.
The extended training squad will gather at the WRU’s National Centre of Excellence, with English-based players joining when their club campaigns end in England.
Lynn, said: “It’s exciting to get to name a first Wales training squad and one full of experienced international players, playing well for their clubs and young exciting players who have shone in the Celtic Challenge.
“To have so many Welsh internationals feature in the Prem semi-finals is a testimony to the players quality and to their performances with their clubs.
“As coaches we have selected players who have really impressed and put their hands up playing for Gwalia Lightning and Brython Thunder in the Celtic Challenge.
“The Celtic Challenge is proving to be a real asset with young Welsh players getting the opportunity to play against teams from Ireland and Scotland full of internationals.
“My rugby philosophy has always been about finding, nurturing and supporting young players and giving them the opportunity to reach their full potential.
“We have selected a group of young Welsh players from age-grade rugby so the coaches and staff can assess where they are but also so they can experience an international environment and the standards expected at this level.
“The Celtic Challenge players and the age-grade players are the future Wales family and have been identified because we believe they have talent to make an impact at the highest level now or in the future.”
Four players from Wales U18s, Isla McMullen, Seren Lockwood, Shanelle Williams and Jorja Aiono will join the senior squad as players of national interest.
Wales Women’s extended training squad
Forwards: Gwenllian Pyrs, Maisie Davies, Abbey Constable, Stella Orin, Allie Watkins, Meg Lewis, Kelsey Jones, Carys Phillips, Rosie Carr, Molly Reardon, Donna Rose, Jenni Scoble, Cadi-Lois Davies, Abbie Fleming, Robyn Davies, Georgia Evans, Natalia John, Alaw Pyrs, Gwen Crabb, Lily Terry, Alex Callender, Alisha Butchers, Kate Williams, Bethan Lewis, Gwennan Hopkins, Lucy Isaac, Bryonie King
Backs: Keira Bevan, Sian Jones, Meg Davies, Ffion Lewis, Seren Singleton, Lleucu George, Kayleigh Powell, Robyn Wilkins, Courtney Keight, Hannah Jones, Carys Cox, Kerin Lake, Hannah Bluck, Meg Webb, Savannah Picton-Powell, Nel Metcalfe, Catherine Richards, Lisa Neumann, Jasmine Joyce, Jenny Hesketh, Niamh Terry
