Gossner et al., 2014 (biology); Heiss, 1998c (syn.); Péricart, 1989 (distr., fig.); Reuter, 1913 (redescr., fig. sordidus); Roubal, 1958b (fig., tax.). Distribution: E. Ribes & J. Ribes, 2000 (Spain); Kanyukova & Vinokurov, 2007 (Russia: ES); Dioli & Salveti, 2012 (Italy); Kment et al., 2013a (Slovakia).