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ISSN 1211-3026 Cas. Slez. MObrazekuz. Opava (A), 58: 61-62, 2009 First record of Polysarcus denticauda (Orthoptera: Tettigoniidae) from the Jeseníky Mts Petr K o c á r e k, Jaroslav H o l u š a & Robert V l k First record of Polysarcus denticauda (Orthoptera: Tettigoniidae) from the Jeseníky Mts. – Cas. Slez. Muz. Opava (A), 58: 61-62, 2009. A b s t r a c t: The contribution gives the first faunistic record of the bush-cricket Polysarcus denticauda from the region of the Jeseníky Mts. and from Silesia. Isolated relict occurrence in the vicinity of the small town Janov represents the third recent occurrence area in the Czech Republic. It concerns a complex of mesophilous tall oatgrass meadows traditionally managed by mowing. At present, the population of this critically endangered species is threatened by an intensive cattle grazing. K e y w o r d s: faunistics, distribution, conservation, Polysarcus denticauda, Ensifera, Czech Republic Polysarcus denticauda (Charpentier, 1825) is a European montane species distributed in Pyrenees, Alps and the Carpathian Mountains (Kocárek et al. 2005). Three isolated areas have been known up to now in the Czech Republic. The most abundant occurrence is still known in the area of the Bílé Karpaty hills (faunistic grid mapping squares (see Prunner & Míka 1996): 7071, 7072, 7073, 7170, 7171), which represents the edge of its Carpathian range. Moreover, it is known from two isolated relict localities outside the main area of distribution: from the environs of Jicín town in Bohemia (5558, 5658) and from the environs of Olomouc town in Moravia (6369). At Olomouc, it has not been confirmed since 1957 and the population has obviously become extinct there. Survey of historical as well as recent occurrences in the Czech Republic was published by Holuša et al. (2007).

    In 2008, the other new isolated locality was recorded thanks to effort of local amateur naturalist Pavel Andráško. The locality, called „Stríbrný žleb“ valley, is situated in the vicinity of the small town Janov and represents the first record from Silesia and from the region of the Jeseníky Mts. The locality is situated on a slope oriented southwards, approximately 1.2 km northwards from Janov town. It concerns a complex of mesophilous mainly tall oatgrass meadows (Arrhenatherion alliance) traditionally managed by mowing. Population of this species was dense here, e.g. during seventieth years of 20th century, even on meadows in proximity to the town (P. Andráško, pers. comm.). Only during the last years, an intensive pasturage of cattle has been started here. It has strongly damaging effect on the meadow vegetation and also threatens local population of P. denticauda so much, that there is real hazard of extinction (P. Andráško, pers. comm.). In 2009, the locality was studied repeatedly with not very stimulative results. At first, at the turn of June and July (July 2, 2009), even during extended investigation no individual has been recorded and the locality was hopelessly devastated by cattle pasturage. However later (July 18, 2009), one individual (male) was detected acoustically and relatively short time after that (July 24, 2009) four individuals (1 male and 3 females) were found and documented by photos. But during next inspection (July 26, 2009), the same place was again found already totally devastated by a cattle herd. At last, one individual (male) was detected acoustically on the opposite side of the valley, which gives to this population certain chance to survive yet. Material examined: Silesia, Jeseníky Mts. region, Zlatohorská vrchovina highlands, Janov (5770), 50°15'24.5"N, 17°28'29"E, 500 m a.s.l., 31.vii.2008, 1/0, P. Andráško observ., supported by photographs (P. Kocárek, J. Holuša, R. Vlk det.); 50°15'12"N, 17°28'25.5"E, 500 m a.s.l., 18.vii.2009, 1/0, P. Andráško observ. (male singing); 50°15'12"N, 17°28'22.5"E, 500 m a.s.l., 24.vii.2009, 1/3, P. Andráško observ., supported by 62 photos (P. Kocárek, J. Holuša, R. Vlk det.); 50°14'26"N, 17°28'54.5"E, 500 m a.s.l., 26.vii.2009, 1/0, R. Vlk, 

   P. Andráško observ. (male singing). Ecological requirements of P. denticauda are known only very poorly, but probably they are very specific, mainly mesoclimaticaly. P. denticauda is herbivorous, obviously polyphagous species. Extensively managed mesophilous meadows with taller and dense vegetation appear to be an optimal habitat, whereas herbaceous species composition is probably not the key factor (Holuša et al. 2007). Despite of increasing number of findings of P. denticauda, it is still necessary to consider this species as critically endangered, as it is mentioned in the Red list of endangered species of invertebrates of the Czech Republic (Holuša & Kocárek 2005). It is obvious, that without implementation of some conservation arrangements, especially restriction of uncontroled grazing, newly discovered population of P. denticauda at the locality „Stríbrný žleb“ in vicinity of Janov town is devoted to extinction. It is also possible that this species occurrs on some other localities in the near surrounding (see so far solitary finding of one male on the opposite side of the river Osoblaha valley mentioned above), nevertheless there are some other no less relevant reasons, why it would be desirable to reduce negative pasturage effects. Acknowledgement The study was partly supproted by grant of the Ministry of Agriculture of the Czech Republic No. 0002070203. References Holuša J., Kocárek P. (2005): Orthoptera (rovnokrídlí), pp. 133-134. In: Farkac J., Král D. & Škorpík M. (eds.): Cervený seznam ohrožených druhu Ceské republiky. Bezobratlí. Red list of threatened species in the Czech Republic. Invertebrates. Agentura ochrany prírody a krajiny CR, Praha, 760 pp. Holuša J., Kocárek P., Marhoul P. (2007): Výskyt kobylky Polysarcus denticauda (Orthoptera: Tettigoniidae) v Ceské Republice. Occurrence of the bush-cricket Polysarcus denticauda (Orthoptera: Tettigoniidae) in the Czech Republic. - Práce a Studie Muz. Beskyd (Prír. vedy), 19: 254-255. Kocárek P., Holuša J., Vidlicka L. (2005): Blattaria, Mantodea, Orthoptera & Dermaptera of the Czech and Slovak Republics. Illustrated key 3. Blattaria, Mantodea, Orthoptera & Dermaptera Ceské a Slovenské republiky. Ilustrovaný klíc 3. Kabourek, Zlín, 349 pp. Prunner L., Míka, P. (1996): Seznam obcí a jejich cástí v Ceské republice s císly mapových polí pro sítové mapování fauny. Klapalekiana, 32 (Suppl.): 1-175. První údaj o výskytu Polysarcus denticauda (Orthoptera: Tettigoniidae) v Jeseníkách

     Příspěvek přináší první údaj o výskytu kobylky Polysarcus denticauda v oblasti Jeseníku a zároveň i ve Slezsku. Izolovaný reliktní výskyt u města Janov představuje třetí recentní oblast výskytu v České republice. Jedná se o komplex mezofilních ovsíkových luk tradičně obhospodařovaných sečením. V současnosti je populace tohoto v ČR kriticky ohroženého druhu ohrožena intenzívní pastvou dobytka. Author' addresses: Petr Kocárek, Katedra biologie a ekologie, Ostravská universita, CZ-710 00 Ostrava; e-mail: petr.kocarek@osu.cz Jaroslav Holuša, Výzkumný ústav lesního hospodárství a myslivosti, v.v.i., Pracovište Frýdek-Místek, Nádražní 2811, CZ-73801 Frýdek-Místek; e-mail: holusaj@seznam.cz Robert Vlk, Katedra biologie, Pedagogická fakulta, Masarykova univerzita, Porící 7, CZ-603 00 Brno; e-mail: vlk@ped.muni.cz