Rory Best will captain Ireland in the Six Nations after being named in a squad which contains four uncapped players.
Ireland head coach Joe Schmidt has given Ulster hooker Best the captaincy duties in his 35-man squad for the tournament, which begins with a game against Wales in Dublin on Sunday February 7.
Connacht forward Ultan Dillane, Munster's CJ Stander, Josh van der Flier of Leinster and Stuart McCloskey of Ulster are the new names on the squad sheet
Tommy Bowe, Iain Henderson, Peter O'Mahony and Dan Tuohy have been left out due to long-term injuries.
Schmidt said: "As always, there were a number of tight decisions, especially with a number of players not being available to play in recent weeks.
"Mike Ross, Cian Healy and Chris Henry are all likely to return to play over the coming weeks and they, along with some of the other players not included will potentially return to the squad post these first two matches.
"There are a few new faces but at the same time we have resisted the temptation to include some of the very promising youngsters, allowing them a bit more time to develop as well as the opportunity of further game time with their provinces."
Ireland squad for Six Nations: Forwards: Rory Best (Ulster) (c), Sean Cronin (Leinster), James Cronin (Munster), Ultan Dillane (Connacht), Tadhg Furlong (Leinster), Jamie Heaslip (Leinster) (vc), Rob Herring (Ulster), Mike McCarthy (Leinster), Jack McGrath (Leinster), Martin Moore (Leinster), Sean O'Brien (Leinster), Tommy O'Donnell (Munster), Rhys Ruddock (Leinster), Donnacha Ryan (Munster), CJ Stander (Munster), Richardt Strauss (Leinster), Devin Toner (Leinster), Josh van der Flier (Leinster), Nathan White (Connacht).
Backs: Keith Earls (Munster), Luke Fitzgerald (Leinster), Robbie Henshaw (Connacht), Paddy Jackson (Ulster), David Kearney (Leinster), Rob Kearney (Leinster), Ian Madigan (Leinster), Kieran Marmion (Connacht), Luke Marshall (Ulster), Stuart McCloskey (Ulster), Conor Murray (Munster), Jared Payne (Ulster), Eoin Reddan (Leinster), Jonathan Sexton (Leinster), Andrew Trimble (Ulster), Simon Zebo (Munster).