Monahans supposedly from near townland of Magheranearla

My great, great, great grandfather James Monahan was, according to another family member and his mother, from near the townland Magheranearla. He was born about 1846. His family immigrated to America when he was a child and eventually settled in St. Louis Missouri. His mother's name according to n obituary article was named Mary. James settled for good later in Quincy, IL and  married a young woman named  Christina. They had several children. Their son John was my great great grandfather and he eventually moved to Iowa had a daughter, Nell Monahan who was my great grandmother. She eventually married, lived in Des Moines, Iowa and took her husband's last name, Winterrowd. Basically I'm hoping to confirm that James was from this area and if so who his parents and/or siblings were. My mom is going to be travelling to Ireland in July and I'd love to be able to tell her where they were from and where to visit. It would be even better to find family still near the area. Any help would be appreciated. Thanks!.