Arthur Wilson Stelfox

Arthur Wilson Stelfox (15 December 1883–19 May 1972) was an Irish naturalist and architect. Stelfox was a recognised authority on Hymenoptera and on non-marine Mollusca especially the genus Pisidium. He also made important contributions to scientific knowledge concerning Irish botany and on identifying and describing remains from prehistoric sites in Ireland.

Stelfox was born in Belfast on 15 December 1883 the son of Jennie McIlwaine and James Stelfox. He was educated at Campbell College, Belfast and went on to study architecture in Ireland and England, being elected as an associate of the Royal Institute of British Architects on the 2 November 1908.

Stelfox was an enthusiastic naturalist from his youth, encouraged by his father, who belonged to the Belfast Naturalists' Field Club and by Robert John Welch with whom he would later collaborate. His earliest known specimens are now held in the National Museums Liverpool and were collected in 1898 when he was 15 years of age.

It was not until 1903 that Stelfox became an official member of the Belfast Naturalists' Field Club and in 1908 he was appointed the Honourable Secretary. In 1909 his future wife Margarita Mitchell was asked to assist him in this role. Mitchell was a talented naturalist in her own right and did valuable work in conjunction with M. W. Rea on Mycetozoa. Stelfox and Mitchell married in 1914. The couple subsequently had three children but sadly their daughter and youngest son died in childhood.

Around 1908, amongst other work, Stelfox assisted with the Clare Island Survey, visiting the Island and the surrounding area on numerous occasions, researching and writing the section of the Survey Report on non-marine mollusks. In 1911 he published a paper in the Proceedings of the Royal Irish Academy and next year he was elected a member of that Academy. One of Stelfox's most influential papers on Mollusca was on the Pisidium fauna of the Grand Junction Canal which was published in 1918. This was regarded by Arthur Erskine Ellis as having "revolutionised the hitherto very unsatisfactory treatment of the genus...".