The 20-year-old second-row/back-row player was capped for Scotland at under-17 and under-18 levels and was previously an apprentice with Glasgow Warriors. He has been a standout performer for the Millbrae men this season and will be looking forward to testing himself at this level.
Templeton is one of 17 uncapped players named in a new-look squad. Forwards who could win their first cap against Ireland on February 7 in Cork include Templeton's Ayr team-mates George Hunter, Fergus Scott and Nick Cox as well as Heriot's hooker George Turner, Hawick prop Lindsey Gibson, Gala prop Ewan McQuillin, Heriot's second-row Russell Nimmo and back-row trio Andy Redmayne (Glasgow Hawks), Will Bordill and Adam Ashe (Stirling County).
There are seven uncapped backs: stand-offs Finn Russell (Ayr) and Richard Mill (Melrose), Edinburgh Accies' utility man Nyle Godsmark, centres Jack Steele (Hawks) and Chris Auld (Gala) and wing Grant Somerville (Gala).
The most experienced man at this level is the Melrose full-back Fraser Thomson, who has seven caps, while the Ayr centre Dean Kelbrick has six appearances from 2011 onwards. Greg Cottrell, the Hawick scrum-half, was capped in 2008 when he was playing for Boroughmuir and will be keen to add to that tally.
There are seven players who train regularly with Glasgow Warriors and three with Edinburgh and while the coaching staff, headed by Hawick's Phil Leck, will contend that these players add quality to the squad, there are others willing to argue that the matches should be for "club" players only.
Leck said: "Our 27-man squad, cut from 41, reflects the players who have begun to put their hands up and stake a claim for jerseys. We're excited about the challenges ahead and feel that starting our preparations pre-Christmas this year has been beneficial and will stand us in good stead."
After the match in Cork, Scotland will face France at Old Anniesland on Friday, March 7. Last season, they beat Ireland but lost in France.
n Scotland Club XV squad
Forwards Alex Allan (Edinburgh Accies/Edinburgh), George Hunter (Ayr/Glasgow), Fergus Scott (Ayr/Glasgow), George Turner (Heriot's/Edinburgh), Lindsey Gibson (Hawick), Ewan McQuillin (Gala/Edinburgh, Nick Cox (Ayr), Murray Douglas (Heriot's), Callum Templeton (Ayr), Russell Nimmo (Heriot's), Andy Redmayne (Glasgow/Glasgow Hawks), Andrew Nagle (Melrose), Will Bordill (Stirling County/Glasgow), Adam Ashe (Stirling County/Glasgow), Gary Graham (Gala).
Backs Greg Cottrell (Hawick), Peter Jericevich (Ayr), George Graham (Gala), Finn Russell (Ayr/Glasgow), Richard Mill (Melrose), Nyle Godsmark (Edinburgh Accies), Grant Somerville (Gala), Jack Steele (Glasgow Hawks/Glasgow), Dean Kelbrick (Ayr), Chris Auld (Gala/Edinburgh), Craig Gossman (Ayr), Fraser Thomson (Melrose).