﻿AbstractThe author provides corrections of minor errors and omissions from his initial study, as well as data from omitted and new literature, and new records based on the material studied and new observations. For some of the previously published records, details obtained subsequently by the author are added. The first record ofBolbelasmusunicornisfor Belarus is given, representing the northernmost known occurrence of the species. The second recent record for Croatia is quoted from an internet source. Updated distribution maps are provided for the Czech Republic and Slovakia, and for the entire range, as well as a distribution map of the Western Palaearctic representatives of theB.unicornisspecies group. The species is currently known from 386 localities in 20 countries.