Scarlets' Munster-bound lock Tadhg Beirne is in line for his Ireland debut after being selected for June's three-Test tour of Australia.
Leinster fly-half Ross Byrne is the only other uncapped player in head coach Joe Schmidt's 32-man squad to face the Wallabies in Brisbane, Melbourne and Sydney.
Second row Beirne will link up with the Ireland squad after facing Leinster in Scarlets colours in Saturday's Guinness PRO14 final.
British and Irish Lions and Ulster hooker Rory Best has retained the captaincy, moving the 35-year-old a step closer to retaining that leadership role for the 2019 World Cup.
"This has probably been the most difficult selection process for the coaching group to date," Schmidt said.
"We sat down on Monday morning to review the last pieces of footage and to discuss the balance and combinations that we felt we might need in Australia.
"At midday today (Wednesday) we made the final decisions which included a number of very tough calls, and some players are incredibly unlucky to miss out on selection.
"Over the past couple of months the national coaches have spent time in the provinces and been in communication with the provincial coaches who have done a super job in managing the players across the season.
"The coaching group are excited by the challenge that this three-Test tour will present and, from talking to the players, we get a sense that they too are excited about going on tour and testing themselves against one of the best sides in the world in their own backyard."
Ireland will face Michael Cheika's Wallabies in Brisbane for the first Test on Saturday, June 9, with clashes in Melbourne and Sydney following on successive Saturdays.
Ireland squad for summer tour to Australia:
Forwards: R Best (Ulster, capt), T Beirne (Scarlets), J Conan, S Cronin, T Furlong, C Healy (all Leinster), I Henderson, R Herring (both Ulster), D Leavy, J McGrath J Murphy (all Leinster), P O'Mahony (Munster), A Porter (Leinster), Q Roux (Connacht), James Ryan (Leinster), John Ryan, CJ Stander (both Munster), D Toner (Leinster).
Backs: B Aki (Connacht), R Byrne, J Carbery (both Leinster), A Conway (Munster), J Cooney (Ulster), K Earls (Munster), R Henshaw, R Kearney, J Larmour (all Leinster), K Marmion (Connacht), C Murray (Munster), G Ringrose, J Sexton (both Leinster), J Stockdale (Ulster).