FIRST RECORD OF THE BUSH-CRICKET ISOPHYA CIUCASI (INSECTA: ORTHOPTERA: PHANEROPTERIDAE) IN MOLDAVIA (ROMANIA)

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1 FIRST RECORD OF THE BUSH-CRICKET ISOPHYA CIUCASI (INSECTA: ORTHOPTERA: PHANEROPTERIDAE) IN MOLDAVIA (ROMANIA) Ionuț Ștefan IORGU "Grigore Antipa" National Museum of Natural History, Kiseleff blvd., no. 1, , Bucharest, Romania, Abstract. The bush-cricket Isophya ciucasi is recorded for the first time outside its locus typicus. Recently described from Ciucaş Mountains, the species was found in Vrancea Mountains in the summer of As the species was described as cryptic morphologically, the acoustic signals of males from the two known populations were compared. Keywords: bush-cricket, Isophya ciucasi, Moldavia, bioacoustics. Rezumat. Prima semnalare a cosaşului Isophya ciucasi (Insecta: Orthoptera: Phaneropteridae) în Moldova (România). Cosaşul Isophya ciucasi este semnalat pentru prima dată în afara locus typicus. Recent descrisă din Munţii Ciucaş, specia a fost găsită în vara anului 2013, în Munţii Vrancei. Deoarece specia a fost descrisă ca fiind criptică morfologic, am comparat semnalele acustice ale masculilor din cele două populaţii cunoscute. Cuvinte cheie: cosaş, Isophya ciucasi, Moldova, bioacoustică. Comprising more than 45 species, Isophya is the second largest Phaneropteridae genus in Europe. From the taxonomical point of view, genus Isophya is one of the most problematic of European Orthoptera, their morphological similarity making identification of species very difficult (Heller et al., 2004). As Isophya are stridulating species, male calling song analysis is usually regarded as the most important instrument for correct identification (Heller et al., 2004; Orci et al., 2010; Iorgu, 2012; Szövényi et al., 2012). The first individuals of Isophya ciucasi Iorgu I.Ş. & Iorgu E.I. were audio recorded in the summer of 2008 in Ciucaş Mountains and the species was later described as new, in Isophya ciucasi is very similar in morphology with Isophya camptoxypha, but the syllables produced during the calling song are different in structure. Until present study, the species was known only from the subalpine plateau of the Ciucaş Mountains, Eastern Carpathians. The bush-crickets were collected during six expeditions in Ciucaş Mountains and one in Vrancea Mountains. Adults and last instar nymphs caught in the wild were transported in aerated plastic containers and audio recorded indoors. The digital recorders EDIROL R-09HR was used. Ultramic200K external microphone was used for obtaining the full spectrum of song. Sound analysis was performed with the software Audacity and Batsound 4. Oscillographic analysis terminology was used according to Heller et al. (2004), Orci et al. (2010) and Iorgu (2012): SD period from the beginning of first impulse to the end of last impulse of the main impulse series of a syllable; NI number of impulses of the main impulse series of the syllable; GS period of time elapsed from the end of a syllable to the beginning of the next syllable; DAC time elapsed from the last impulse of the main

2 Ionuț Ștefan Iorgu impulse series of the syllable to the first after-click (-s); NAC number of after-clicks produced after a syllable; STD period from the beginning of first impulse to the end of last impulse of the main impulse series of a syllable, or end of its last after-click, if present. Photos were taken with a Canon DSLR camera, equipped with 100 mm 1:1 macro lens and mm lens. Order Orthoptera Suborder Ensifera Family Phaneropteridae Isophya ciucasi Iorgu I.Ş. & Iorgu E.I., 2010 (Fig. 1) Material examined. 2 1, Ciucaş cabin, Ciucaş Mountains, 1585 m a.s.l., , leg. I.Ş. Iorgu; 3 3, Ciucaş cabin, Ciucaş Mountains, 1600 m a.s.l., , leg. I.Ş. Iorgu; 23 9, Tigăile Mari, Ciucaş Mountains, , leg. I.Ş. Iorgu; 10 4, Ciucaş cabin, Ciucaş Mountains, , leg. I.Ş. Iorgu; 7 5, Tigăile Mari, Ciucaş Mountains, , leg. I.Ş. Iorgu; 2 1, Ciucaş cabin, Ciucaş Mountains, , leg. I.Ş. Iorgu; 8 3, Goru, Vrancea Mountains, , leg. I.Ş. Iorgu. Audio recordings. 2, Ciucaş cabin, Ciucaş Mountains, (24ºC); 3 3, Ciucaş cabin, Ciucaş Mountains, (27ºC); 19 6, Tigăile Mari, Ciucaş Mountains, (24ºC); 7, Ciucaş cabin, Ciucaş Mountains, (26ºC); 3, Tigăile Mari, Ciucaş Mountains, (25ºC); 2, Ciucaş cabin, Ciucaş Mountains, (24ºC); 4, Goru, Vrancea Mountains, (20ºC). Remarks. Males sing at dusk and during the night. The song consists of a long series of syllables, sometimes lasting for more than 20 minutes. Each syllable is formed of a compact series of impulses, always followed by several after-clicks. All sounds are produced during the closing stroke of tegminae. Spectrographic analysis indicates frequencies between khz (Fig. 2). First data on the song (8 recorded in 2008 and 7 in 2009) showed that the compact series of impulses (mean ± SD: 18.4 ± 4.82) lasts for ms (mean ± SD: 18.2 ± 4.32) and the following after-clicks (13-23 impulses, mean ± SD: 17.6 ± 3.71) last for ms (mean ± SD: 228 ± 25.31) (Iorgu & Iorgu, 2010). New recordings in the type locality (33 recorded in 2010, 7 in 2011 and 2 in 2012) showed a higher amplitude in song characteristics (Fig. 2, Table 1). Compared with males from Ciucaş, specimens from Vrancea showed insignificant differences in song production: relative longer syllable duration (mean ms, respectively ms) and delay of after-clicks (mean ms, respectively ms)

3 Figure 1. Habitus and habitat photos of Isophya ciucasi: a - female, Ciucaş Mountains, ; b - male, Ciucaş Mountains, ; c - male, Vrancea Mountains, ; d - female, Vrancea Mountains, ; e - Ciucaş Mountains, ; f - Vrancea Mountains, Goru Peak,

4 Ionuț Ștefan Iorgu Figure 2. Sound analysis in Isophya ciucasi males: a, b - oscillograms; c, d - detailed syllable; e - spectrum; f - spectrogram (a, c, e, f - Vrancea Mountains; b, d - Ciucaş Mountains). Ciucaş (n = 34, 24-28ºC) Vrancea (n = 4, 20ºC) Table 1. Examined male song characters in Isophya ciucasi SD (ms) NI GS (ms) DAC (ms) NAC STD (ms) Min Max Mean S.D Min Max Mean S.D

5 Acknowledgements The present study was supported by project Completing and improving the information on wildlife species from Putna Vrancea Natural Park in accordance with national standards. We acknowledge the anonymous reviewers for their advices on improving the paper. References Heller, K.-G., Orci, K.M., Grein, G., Ingrisch, S., The Isophya species of central and western Europe (Orthoptera: Tettigonioidea, Phaneropteridae). Tijdschrift voor Entomologie, 147: Iorgu, I.Ş., Acoustic analysis reveals a new cryptic bush-cricket in the Carpathian Mountains (Orthoptera, Phaneropteridae). ZooKeys, 254: Iorgu, I.Ş., Iorgu, E.I., A new species of Isophya (Orthoptera: Phaneropteridae) from the Romanian Carpathian Mountains. Travaux du Muséum d Histoire Naturelle Grigore Antipa, 53: Iorgu, I.Ş., Iorgu, E.I., Bioacoustics in bush-crickets, crickets and grasshoppers (Insecta: Orthoptera) from Ciucaș Mountains (Eastern Carpathians, Romania). Brukenthal. Acta Musei, VI.3: Orci, K.M., Szövényi, G., Nagy, B., A characterisation of the pair forming acoustic signals of Isophya harzi (Orthoptera, Tettigonioidea, Phaneropteridae). Acta Zoologica Academiae Scientiarum Hungaricae, 56(1): Szövényi, G., Puskás, G., Orci, K.M., Isophya nagyi, a new phaneropterid bush-cricket (Orthoptera: Tettigonioidea) from the Eastern Carpathians (Caliman Mountains, North Romania). Zootaxa 3521: