Leitrim-Roscommon

In researching my Carlos family I find the spelling of Carlis (one entry spelled Carlos) in the Tithe records ca 1825-1833, but I find Carlisk/Carlick on the Elphin census.The IGI lists a Petri Carlisk, and also lists the same person in a duplicate entry as Petri Carlos. I also find a Patriti Carlisk also duplicated as Patrick Carlos. This indicates to me that the Carlis(c)k spelling found in the Elphin Census is the same family. We have reason to believe that the family has been in the Lissonuffy area for hundreds of years (Sharkey reference to the Duffy/Carlos earthen fort and church). I am at an end in my personal research- no records of birth for my ancestor Peter Carlos b abt 1800-1810 in CloonyCarran More. I am now researching the surname in general. I find these entries in the 1749 Elphin Census:

Parish Bumlin, Townland Cullegh (later Culliagh Upper and Lower and adjacent to Gortoose, known in 1828 as GortooseCarlis and GortooseMurray)Mathew Carlick -laborer-and wife Catherine, 4 children under age 14, Papists

Parish Lissonuffy, Townland CloonCarran (known later as CloonCarran More, then Cloonycarran More, adjacent to BallyDuffy)
Charles Carlick-cowherd- and wife Mary, 2 children under age 14, Papists

Parish Cloonfinlough, Townland Clooniragh (later known as Cloonerra?)
Michael Carlisk -tenant- and wife, 1 child over age 14, 2 under age 14, Papists

Parish Cloonfinlough, Townland Clunilion (later known as Cloonylyon?)
Robert Carlisk -tenant- and wife, no children, Papists
Mathew Carlisk -tenant- and wife, no children, Papists

Any hints or comments would be greatly appreciated from anyone else researching this surname. It appears that the name was Carlis(c)k, then Carlis, then Carlos. I am trying to determine the precursor to Carlisk- MacCarluis? McCarlais? McCoirleasa? Corliss? MacCathail? And the odd connection to DunCatha? I also have researched and recorded in a spreadsheet all entries for the surname found in the 1749 Elphin Census, the 1823-1835 Tithe records, the Griffiths Survey, and the 1901 census. If anyone has a Carlos family they are researching, please email me directly and perhaps we can sort things out together.

Footnote- while in Wisconsin digging around for land records of Peter Carlos I found that the first parcel he purchased in 1847 was adjacent to a parcel owned by Patrick Duffy. Amazing to read about the Duffy/Carlos connection of hundreds of years in Lissonuffy, then to see it again in the obscure farming community of Rubicon, Dodge County Wisconsin, centuries later!

This is not an answer to your questions, but I have a Michael Carlos recorded as godparent along with Bridget Conlon, for John McCormick in November 1860, Strokestown R.C. Church. John was the son of John and Catherine McDonnnell McCormick, who lived in Corboghil, parish of Cloonfinlough.