On April 2, 2013 the Dutch malacologist Hendrikus Johannes (Henk) Hoenselaar died at the age of 87. As a technician he was an employee of Shell Nederland, and spent his military service in the Royal Netherlands navy. After that he became a teacher and later on director of a technical school. He married Jos van Zoelen and they got a daughter and a son. After early retirement they started to collect minerals and fossils. Both became honorary associates of the Zoölogisch Museum Amsterdam. They travelled all around Europe. Initially their collecting activities were focussed on the marine molluscs from the Atlantic and Mediterranean. In later years they also started to collect European land snails. Henk published more than 40 malacological papers. Two species and one genus were named after him and he described 29 species new for science. Their collection was donated to the Zoölogisch Museum Amsterdam and is nowadays part of the malacological collection of Naturalis, Leiden, the Netherlands.