Alfred Nalepa (19.XII.1856–11.XII.1929), an Austrian acarologist, described about 460 eriophyoid species. He reported new taxa in short communications usually published in “Anzeiger der Kaiserlichen Akademie der Wissenschaften in Wien” and later prepared detailed descriptions for separate publication. For most Nalepan species the date of the first listing in Anzeiger is the valid date of the taxon name. His archive, library and collection are kept in the Natural History Museum of Vienna, Austria (NHMW). The collection consists of 24 boxes with 1073 vials containing plant material with extracted mites collected during 1887–1929. All boxes are labeled according to the first letters of the host-plant names and are sorted alphabetically; the vials are numbered and labeled. A jotter, presumably representing the hand-written catalog of the vial collection, and work diaries, containing indications of numbers of the vials, were found in the Nalepa archives. Nalepa used picric acid, hydrochloric acid, ethanol, formalin and creosote for preservation of mites. In all vials the preservative totally evaporated so that only dry sediment remains at the bottom of the vials. A solution containing ethanol, ether and acetic acid was found to be appropriate for dissolving the sediment. A simple, fast protocol for recovering mites from vials and making good slides was developed. It includes four steps: 1) opening the vial; 2) dissolving the sediment; 3) treating mites in lactic acid; 4) slide mounting. All digital data obtained from the Nalepa archives (database of the vials, copies of the jotter, reprints and drawings of mites) will be available for scientists at the web site of NHMW  http://www.nhm-wien.ac.at/en/nalepa.