Contributions to the study of the genus Mongolojassus Zakhvatkin, 1953 (Homoptera: Cicadellidae: Deltocephalinae: Paralimnini) with description of a new species from Northern Caucasus Author Tishechkin, Dmitri Yu. text Zootaxa 2022 2022-04-22 5128 4 574 580 journal article 55835 10.11646/zootaxa.5128.4.6 865bba99-265d-42b8-a515-ec3bb467071a 1175-5326 6480088 35260FDC-F72E-4241-87C5-194B9D94893B Mongolojassus elpatjevskii ( Zakhvatkin, 1953 ) Figs. 32–34 Most specimens of Auchenorrhyncha investigated by Prof. Zakhvatkin are deposited in the collection of the Zoological Museum of Moscow State University. However, type specimens of a considerable number of his species are absent in the collection, and male specimens usually lack genital segments. For this reason, we found it useful to provide information about the type series of M. elpatjevskii . The original description ( Zakhvatkin, 1953 ) is based on two males and two females . All four specimens are present in the collection, among them holotype , ♀ ( Fig. 32 ), with labels: “L. [Lake] Kosogol [misspelled “Khubsugul”], V . S. Elpatyevsk [y].”, “Mth. [Mouth] R . [of the River] Khabtsyl, 5. VIII. [19]03” (in Russian, comments in square brackets), “Cotypus”, and “Delt. sp. nov. prop. bellevoyei Put. A. Zachvatkin det.” ( Fig. 33 ) and paratypes , 2 ♂ , both dissected, genitalia preparations are absent ( Fig. 34 ), 1 ♀ with only two first labels same as in holotype , “ L. Kosogol , V . S. Elpatyevsk. ” and “Mth. R . Khabtsyl, 5. VIII. 03” . This species is similar in appearance to other species of Mongolojassus ( Figs. 32, 34 ). Drawings of the aedeagus were published by Zakhvatkin (1953) and Dlabola (1965) . The description of M. elpatjevskii was published after the death of Prof. Zakhvatkin in a collection of works, the manuscripts of which, in a more or less finished form, were found in his archive. For this reason, some works contain omissions or inaccuracies. In particular, in the description of M. elpatjevskii there is a contradiction concerning the generic placement of this species. The description begins as follows. “ Deltocephalus elpatjevskii A. Zachvatkin , sp. n. — 2 ♂♂ , 2 ♀♀ ( Fig. 2 ). The mouth of the Khabtsyl River , 5/VIII . Close to D. sibiricus Horv. 1901 , forming together with it a sharply separated association, belonging to the wellknown group “ocellati”, which, of course, can be separated as a special genus ( Mongolojassus A. Zachvatkin , g. n. ; typ. gen. Deltocephalus sibiricus Horv. 1901 ). Very similar in general appearance, type of coloration and anatomical features to D. sibiricus , only somewhat stouter and distinctly smaller [below, the description of the species follows]” ( Zakhvatkin, 1953: 249 ). Thus, this species was described in the genus Deltocephalus Burmeister, 1838 , but was immediately attributed to the new genus, Mongolojassus in the same publication. Therefore, the original combination with Deltocephalus can be considered a lapsus attributable to the unfinished nature of Zachvatkin’s manuscript, given the author’s clear intent to include both D. sibiricus and “ D. elpatjevskii ” in Mongolojassus .