The initiative is a pilot for the WRU, SRU and IRFU, supported by World Rugby to help raise standards in the women’s game.
The hosts enjoyed the bulk of the early possession and were able to make good ground after asserting their dominance in the scrum.
The Thistles were soon deep into the WRU Development XV territory, but the visitors did well to steal a line-out on the 5m and eventually were able to clear their lines.
The WRU Development XV soon found their stride and were first on the scoreboard as Rosie Carr powered over into the corner to score.
Buoyed by the early score, the visitors were creeping towards the line once again. The side were awarded a scrum 5m out from the try-line, but another strong showing from The Thistles saw the hosts win a penalty to relieve the pressure.
The tables soon turned when full-back Roma Fraser sprinted down the pitch to score in the corner and bring the game back to a level.
The Thistles were persistent in their attack and were able to take the lead as Holly McIntyre raced her way over the line.
The WRU Development XV were able to rally ahead of the interval, as flanker Gwennan Hopkins punctured her way through the defence to score, with the game at a level 10-10 going into the break.
It was a bright start to the second-half for WRU Development XV as captain Abbie Fleming picked up the ball from the base of the ruck and bustled through the defence for a try, with Chelsea Jones adding the extras.
The Thistles retort was prompt, as Francesca McGhie raced down the wing to score, but the conversion attempt fell short, allowing WRU Development XV to hold a narrow two-point lead at 15-17.
The hosts were able to pile on the pressure once again as Rachel Philipps was close to crossing the line but some fantastic defence from the Welsh side saw Philipps being bundled into touch just 5m from the line.
The Thistles were back in the lead following a try from close range by Panashe Muzambe, with Meryl Smith adding the extras..
The visitors soon were able to take back the lead as Wales hooker Kat Evans crossed the whitewash, with Chelsea Jones converting the score 22-24.
The Thistles were able to pull themselves back into contention as Francesca McGhie grabbed her second try of the match after cruising her way through the defence to score to put the home 27-24 ahead.
The WRU Development XV side rallied and never gave up and Ffion Owens found her way to the try line to seal the victory.
The Thistles: Roma Fraser (Cartha Queens Park); Holly McIntyre (University of Edinburgh), Emma Orr (Biggar), Meryl Smith CAPTAIN (University of Edinburgh), Francesca McGhie (Watsonians); Sarah Denholm (University of Edinburgh), Mairi McDonald (Exeter Chiefs); Panashe Muzambe (Exeter Chiefs), Aila Ronald (University of Edinburgh), Elliann Clarke (University of Edinburgh), Erinn Foley (Hillhead Jordanhill), Natasha Logan (University of Edinburgh), Eva Donaldson (University of Edinburgh), Jess Fyfe (Cartha Queens Park), Freya Walker (Watsonians)
Replacements: Nikki Simpson (Garioch), Lindsay McDiarmid (Garioch), Molly Poolman (Watsonians), Charlotte Boan (Cartha Queens Park), Emma Turner (Corstorphine Cougars), Rhea Clarke (University of Edinburgh), Carla McDonald (Hillhead Jordanhill), Rachel Philipps (University of Edinburgh).
Welsh Development XV: Leanne Burnell (Pontyclun Falcons); Amelia Tutt (Loughborough Lightning), Catherine Richards (Cardiff Met), Jenna De Vera (Scarlets U18s/ Burry Port), Anwen Owen (Nelson Belles / Bristol Bears); Lauren Smyth (Bristol Bears), Niamh Tinman (Pontyclun Falcons/ Cardiff Met); Rosie Carr (Pontyclun Falcons/ Cardiff Met), Kat Evans (Saracens), Danielle Dinapoli (Cheltenham Tigers), Charlie Mundy (Pontyclun Falcons), Abbie Fleming (capt, Exeter Chiefs), Gwennan Hopkins (Hartpury College), Katie Hopkins (Pontyclun Falcons), Mel Gnojek (Seven Sisters)
Replacements: Tara Finnegan (Pontyclun Falcons), Dali Hopkins (Ospreys U18s/ Greyhounds), Abbey Constable (Gloucester Hartpury / Cheltenham Tigers), Ffion Owen (Pontyclun Falcons / Cardiff Met), Kira Philpott (Llandaff North), Seren Singleton (Cardiff Met), Chelsea Jones (Nelson Belles), Danai Mugabe (Cardiff Met)
Referee: Jonny Perriam
