Abstract
On the basis of the song and morphological analyses, we revised the status of the subspecies Stenobothrus eurasius eurasius Zubowsky, 1898, and S. eurasius hyalosuperficies Vorontsovskii, 1927. The status of the subspecies S. eurasius hyalosuperficies Vor. has been changed to the species level. The most striking difference between S. eurasius and S. hyalosuperficies lies in the song parameters. The calling songs differ not only in temporal parameters but are also produced by different mechanisms. S. eurasius generates calling songs by common leg stridulation, whereas S. hyalosuperficies produces sound by wing clapping. The courtship songs of both species are complex (contain several elements) and very different in temporal structure. The morphological differences between the two species are not as striking as the differences in bioacoustics: we found the only differences in the hind wing venation. At the same time, we suggest these differences to be important since they might be due to different mechanisms of sound production. We revised the ranges of the two species on the territory of Ukraine, Russia and Kazakhstan. We also reviewed the type localities of S. eurasius Zub. and designated lectotype and paralectotype of this species.
References
Bey-Bienko, G.Y. & Mistshenko, L.L. (1951) Locusts and grasshoppers of the USSR andadjacent countries. Part II. Academy of Sciences of USSR Publ., Moscow-Leningrad, 287 pp. [in Russian, English translation: 1964, Jerusalem, Israel Program for Scientific Translations]
Berger, D. (2008) The evolution of complex courtship songs in the genus Stenobothrus Fischer 1853 (Orthoptera, Caelifera, Gomphocerinae). Unpublished doctoral thesis, Friedrich- Alexander-Universität Erlangen-Nürnberg, Erlangen, 169 pp.
Bukhvalova, M.A. & Vedenina, V.Yu. (1998) Contributions to the study of acoustic signals of grasshoppers (Orthoptera: Acrididae: Gomphocerinae) from Russia and adjacent countries. I. New recordings of the саlling songs of grasshoppers from Russia and adjacent countries. Russian Entomological Journal, 7 (3–4), 109–125.
Elsner, N. (1974) Neuroethology of Sound Production in Gomphocerinae Grasshoppers (Orthoptera: Acrididae) I. Song Patterns and Stridulatory Movements. Journal of Comparative Physiology, 88, 67–102.
https://doi.org/10.1007/BF00695923
Elsner, N. (1994) The search for the neural centres of cricket and grasshopper song. In: Schildberger K. & Elsner N. (Eds.), Neural Basis of Behavioral Adaptations. V. 39. Fortschritte der Zoologie. G. Fischer Verlag, Stuttgard, New-York, pp. 167–194.
Elsner, N. & Wasser, G. (1995) Leg and wing stridulation in various populations of the gomphocerine grasshopper Stenobothrus rubicundus (Germar 1817). I. Sound patterns and singing movements. Zoology, 98, 179–190.
Faber, A. (1953) Laut- und Gebдrdensprache bei Insekten (Orthoptera). Mitteilungen des Staatlichen Museums fьr Naturkunde, Stuttgart, 198 pp. [in German]
Harz, K. (1975) Die Orthopteren Europas II. Series Entomologica, 11, 939.
Hedwig, B. (2000) A highly sensitive opto-electronic system for the measurement of movements. Journal of Neuroscience Methods, 100, 165–171.
https://doi.org/10.1016/S0165-0270(00)00255-7
Helversen, O.von. & Elsner, N. (1977) The stridulatory movements of acridid grasshoppers recorded with an opto-electronic device. Journal of Comparative Physiology, 122, 53–64.
https://doi.org/10.1007/BF00611248
Helversen, O.von. & Helversen, D.von. (1994) Forces driving coevolution of song and song recognition in grasshoppers. In: Schildberger K. & Elsner N. (Eds.), Neural Basis of Behavioral Adaptations. V. 39. Fortschritte der Zoologie. G. Fischer Verlag, Stuttgart, New-York, pp. 253–284.
Mařan, J. (1958) Ueber das vorkommen Stenobothrus (subs. Stenobothrodes Tarb.) eurasius Zub. in der Tschechoslowakei Orthoptera – Acrididae. Acta Entomologica Musei Nationalis Pragae, 32 (525), 537–543. [in German]
Otte, D. (1970) A comparative study of communicative behavior in grasshoppers. Miscellaneous Publications, 141, 1–167.
Ragge, D.R. & Reynolds, W.J. (1998) The Songs of the Grasshoppers and Crickets of Western Europe. Harley Books, Natural History Museum, London, 591 pp.
Savitsky, V.Yu. & Lekarev, A.Yu. (2007) New data on acoustic communication and sexual behavior of grasshoppers (Orthoptera: Acridoidea) from semi-deserts and deserts of Russia and adjacent countries. Russian Entomological Journal, 16 (1), 1–38. [in Russian, English abstract]
Sradnick, J., Klöpfel, A., Elsner, N. & Vedenina, V. (2016) Variation in complex mating signals in an “island” hybrid zone between Stenobothrus grasshopper species. Ecology and Evolution, 6 (14), 5057–5075.
https://doi.org/10.1002/ece3.2265
Tarbinskii, S.P. (1948) Order Saltatoria (Orthoptera) – Prygajusjie prjamokrylye. In: Tarbinskii, S.P. & Plavilschikov, N.N. (Eds.), Opredelitel’ nasekomykh evropeiskoi chasti SSSR. OGIZ-Sel’khozgiz, Moscow, St.-Petersburg, pp. 76–127. [in Russian]
Vedenina, V. & Mugue, N. (2011) Speciation in gomphocerine grasshoppers: molecular phylogeny versus bioacoustics and courtship behavior. Journal of Orthoptera Research, 20, 109–125.
https://doi.org/10.1665/034.020.0111
Vedenina, V., Sradnick, J., Klöpfel, A. & Elsner, N. (2012) A narrow hybrid zone between the grasshoppers Stenobothrus clavatus and Stenobothrus rubicundus: courtship song analysis. Biological Journal of the Linnean Society, 107, 383–397.
https://doi.org/10.1111/j.1095-8312.2012.01935.x
Vorontsovskii, P.A. (1927) Materialy k poznaniju fauny Acridodea Orenburgskogo kraja. Izvestija Orenburgskoi stantzii zaschity rastenii, 1, 5–7. [in Russian]
Willemse, F. (1974) Stenobothrus (Stenobothrodes) eurasius macedonicus subspec. nov. from Macedonia (Orthoptera, Acrididae). Enthomologische Berichten, 34, 180–184.
Zubowsky, N. (1898) Zur Acridiodea-Fauna des asiatischen Russlands. Annuaire du Musee Zoologique de l‘Academie des Sciences de St. Petersbourg, 3, 68–110. [in German and Latin]