Lilian Daphne Mayo was born at Balmain North, Sydney on 1 October 1895 to English-born parents. Her parents, William McArthur Mayo (1868-1954) and Eliza Mary (Lila), née Saxelby (1870-1959), had an older son Richard Mayo (who died in 1925). The family moved to Highgate Hill, Brisbane when she was young. She received a Diploma in Art Craftsmanship from the Brisbane Central Technical College in 1913 and in the same year was the winner of the Queensland Wattle Day League travelling art scholarship. From 1920 to 1923 Mayo attended the Royal Academy Sculpture School in London. She returned to Brisbane in 1925 after the death of her brother. She is noted for her large scale public artworks in Brisbane including the Brisbane Tattersall's Club frieze (1926), the tympanum and concert hall frieze of the new City Hall (1927-30), tympanum and Stations of the Cross for the Church of the Holy Spirit, New Farm (1929-30), Queensland Women's War Memorial, Anzac Square (1929-32), and relief panels for the chapel of Mt Thompson Crematorium (1934). In 1929 she co-founded the Queensland Art Fund with friend Vida Lahey. Mayo was foundation trustee of the Godfrey Rivers Trust and was the main buyer for most of the works acquired by the Trust for the Queensland National Art Gallery (now the Queensland Art Gallery). In 1938 and 1939 she travelled in Europe and North America to observe art developments. Between 1940 and 1942 she completed the bronze doors for the Public Library of New South Wales. In 1949 Mayo was awarded the Member of the order of the British Empire for contributions to art. Other works include: The King's School War Memorial, Paramatta (1948-1953); portrait bust of J.D. Story (1954-1956); portrait bust of Field Marshall Sir Thomas Blamey, the Australian War Memorial, Canberra (1957-1958); The Jolly Swagman Statue, the Public Swimming Pool, Winton (1959); portrait bust of Lloyd Rees, the Art Gallery of South Australia; statue of Sir William Glasgow, Brisbane (1961-1964); Statue of a Youth, Knox Grammar School, Sydney (1962 to 1964); and Trophy, the Winton Bronze Swagman Award for Bush Verse (1970-1971). In 1960 Daphme Mayo was appointed the Queensland Art Gallery's first woman trustee. While undertaking these various works, she also earnt a living as a property owner and grew an investment portfolio in bonds and shares. In 1973 she sold her Highate Hill property and retired from public life. The 1970s saw a decline in her health. She died at Brisbane on 31 July 1982.

"Lilian Macarthur" is a pseudonym of Daphne Mayo's. It is a combination of her first name and the middle name of her father.