Checklist of British and Irish Hymenoptera - Sawflies, ' Symphyta' Author Liston, Andrew D. Author Knight, Guy T. Author Sheppard, David A. Author Broad, Gavin R. Author Livermore, Laurence text Biodiversity Data Journal 2014 2 1168 1168 http://dx.doi.org/10.3897/BDJ.2.e1168 journal article http://dx.doi.org/10.3897/BDJ.2.e1168 1314-2828-2-1168 Pachynematus clitellatus (Serville, 1823) Nematus clitellatus Serville, 1823 Nematus trisignatus ( Foerster , 1854, Nematus ) Pachynematus foveolatus Konow, 1903 Pachynematus truncatus Benson, 1948 Pachynematus extensicornis (Norton, 1861): misident. Distribution England, Scotland, Wales, Ireland Notes Taeger and Blank (1998) regard Pachynematus clitellatus and Pachynematus fallax as morphologically highly variable species, which together include most of the previously described W. Palaearctic taxa. Their arguments for this are well reasoned, but at present it seems prudent to continue to regard several of the more distinctive morphological segregates, treated as species by Benson (1958) , as separate taxa, because morphologically intermediate specimens are rare (at least in the male sex). The taxonomy of the whole group requires further intensive work, including genetic analysis. According to Taeger and Blank (1998) Pachynematus kirbyi , treated here as valid, is a synonym of Pachynematus clitellatus .