Try looking at Griffiths Valuation records on the Clare Library website: www.clarelibrary.ie
The following records are found for Thomas Tierney in Inchicronan/Crusheen in 1855 (according to Griffiths):
Tierney Thomas Ballygassan Inchicronan Clare Tierney Thomas DerryvetInchicronan Clare Tierney Thomas Knockreddan Inchicronan Clare
Do you have the names of Thomas and his wife's parents?
You could try looking her father up in Griffiths as well (or at least the surname).
The Clare Library site has a good map of Clare and then of the Parish of Inchicronan which will show you the three townlands mentioned above. You can then narrow your search for Quigleys to those who live in the same or nearby townlands to the Tierneys mentioned above.
Also, have you tracked down their passenger/shipping records.
What about their death certificates or all of their children's birth certificates or marriage certificates?
If you are doing any other lines (of the family) in Ireland the following website is good: http://www.brsgenealogy.comhttp://www.brsgenealogy.com