Isoperla difformis Klapálek, 1909

Bojková, Jindřiška, Soldán, Tomáš & Cr, Biology Centre As, 2013, Stoneflies (Plecoptera) of the Czech Republic: species checklist, distribution and protection status, Acta Entomologica Musei Nationalis Pragae 53 (2), pp. 443-484 : 455

Isoperla difformis Klapálek, 1909

Isoperla difformis Klapálek, 1909 in KLAPÁLEK & GRÜNBERG (1909): 51 (original description)

Comment. The species was described by Klapálek in KLAPÁLEK & GRÜNBERG (1909), from ‘Dresden (Schiller), Bohemia and Denmark’. Type locality was limited to ‘Dresden, Germany’ by ILLIES (1966) but did not designate the lectotype. In 1980, P. Zwick labelled one ♀ of I. difformis (Dresden, leg. Schiller) in the Klapálek collection as lectotype. However, this designation was not published. The material mentioned in KLAPÁLEK & GRÜNBERG (1909) was previously used by KLAPÁLEK (1900) for the description of the male and the larva of Chloroperla helvetica Schoch, 1885 : Zlatá stoka stream near Třeboň (April 1896 and 15. 4. 1897), Nežárka river in Veselí (28. 4. 1897) and Dresdner Haide in Dresden (1 ♂ 2 ♀♀, 30. 4. 1889, leg. Schiller). Material from Zlatá stoka and Nežárka is deposided in the Klapálek collection and actually represents Isoperla difformis . Chloroperla helvetica Schoch, 1885 is considered a junior synonym of Isoperla rivulorum (Pictet, 1841) according to ILLIES (1955). All the above mentioned material is deposited in the National Museum in Prague, the Klapálek collection.