Review of the Balkan Isophya (Orthoptera: Phaneropteridae) with particular emphasis on the Isophya modesta group and remarks on the systematics of the genus based on morphological and acoustic data Author Dragan P. Chobanov Author Beata Grzywacz Author Ionuţ Ş. Iorgu Author Battal Cιplak Author Maya B. Ilieva Author Elżbieta Warchałowska-Śliwa text Zootaxa 2013 3658 1 1 81 journal article 39033 10.11646/zootaxa.3658.1.1 0adf09ba-5301-4828-abf6-8dbe89f041ca 1175-5326 246551 C02D1C74-25C0-41DD-B098-62098EB7B62A Isophya plevnensis Peshev, 1985 sensu novo ( Figs 12, 13 , 41 , 66 , 90 , 115 , 152 , 157 , 192 ) Isophya plevnensis Peshev : Peshev 1985 (sp.n.). Isophya pravdini pravdini Peshev , syn.n. : Peshev 1985 (sp.&ssp.n.). Morphological description : Peshev 1985 (both as I. plevnensis and I. pravdini pravdini ). Karyotype : Warchałowska-Śliwa et al. 2008 (as I. pravdini pravdini ). Synonymy : Peshev (1985) described I. plevnensis and I. pravdini pravdini in the same publication comparing them only with I. modesta and not to each other. The small differences noted and the new data gathered from morphology and song were not sufficient to recognise these two taxa. Therefore we regard them as subjective synonyms and accept the name Isophya plevnensis as valid due to its first mentioning in the latter publication. Furthermore, I. pravdini was described as a polytypic species with three subspecies, each belonging to a different species (Chobanov 2009a; see below) and thus placing I. pravdini in synonymy maintains the stability and universality of nomenclature as per the requirements of the ICZN (1999). Supplement to the description and a diagnosis : Body colouration dark green or blueish-green. Colouration of the lateral parts of tergites has a tendency to opalescence. The disc of tegmina in both sexes is dark, brownishgreen. Male tegmina have brown stridulatory area. CuP is light, yellowish, longer and thicker than that in I. miksici and I. clara , about 2/3–3/4 of the width of metazone. Male tegmina are slightly uplifted due to the vertical costal area but their discs are not distinctly bulged. The stridulatory file ( Figs 152 A) has a length of 3.2–3.7 mm—longer than that of I. miksici and about equal to that of I. andreevae , but has a larger number of teeth (100–130). The female stridulatory apparatus is shown in Fig. 152 C. The apex of male cerci bears a wide pointed tooth ( Fig. 152 B), which is longer than that of I. miksici (and the Belgrade populations of I. clara ) and wider than that of I. andreevae and the typical I. clara . The song ( Fig. 157 ) is hardly recognisable from that of I. andreevae though the syllables’ shape (amplitude modulation) slightly differs (cf. Figs 148, 149 with 157). From the song of I. miksici (and partly I. clara ) it differs in longer syllables, longer syllable interval, smaller groups of syllables, bigger number of impulses within the syllable, and very rare occurrence of after-clicks. FIGURES 150–155. SEM of taxonomically important structures of Isophya : 150, 151— I. miksici (150—BG: Gorski Dom Lodge; 151—BG: Iskar); 152— I. plevnensis (152A—BG: Chernelka Canyon; 152B, C—BG: Apriltsi); 153— I. longicaudata adamovici (BG: Karandila Locality); 154— I. longicaudata longicaudata (BG: Bolata Valley); 155— I. m. modesta (= intermedia ) (RO: Babadag). A—male stridulatory file (scale 1 mm); B—ventro-apical view of apex of male cerci (152B deformed) (scale 100 μm); C—female stridulatory apparatus (scale 500 μm). Bioacoustics : The song was investigated in specimens from two localities near Apriltsi (Stara Planina Mountain foothills) at 25–27°С and consists of single or groups of two syllables (rarely up to 4). The interval between the syllables was usually 2–4 s up to more than 7 s. The syllables had 26–44 impulses (mean 39±3; n=43) and lasted 222–390 ms (mean 283±48; median 260; n=43). Of the available records only two syllables had a single after-click and thus the syllables had a total length of 530–540 ms. The intervals between impulses, similarly to these in I. andreevae and I. miksici , are longer at the beginning of the syllable and shorter at its end (sometimes increasing between the last 2–3 impulses) having length of (3)5–15 ms (mean 7.4 ms), up to 20 and even 32 ms between first impulses. The number of impulses and the syllables length varied between individuals and, contrary to the expectations, at 27°С the values were higher than at 25°С, which obviously reflects individual peculiarities. This supports our decision not to regard the difference of 1°С between the air temperatures during the recordings of I. miksici and I. plevnensis (27 and 28 °С) as resulting in bigger differences between the songs of these taxa. Though the great similarities, the significant differences between song parameters and number of stridulatory teeth (as well as some morphologic differences) support the distinction between the latter taxa. FIGURES 156–161. Male calling song at two different speeds (air temperature at recording shown; time scale below): 156— I. miksici (BG: Gorski Dom Lodge); 157— I. plevnensis (BG: Apriltsi); 158, 159— I. longicaudata adamovici (BG: Karandila Locality, two males); 160— I. longicaudata longicaudata (BG: Bolata Valley); 161— I. modesta modesta (RO: Babadag). Break-signs in Fig. 161B indicate the missing silent interval of the syllable shown in Fig. 161A. Distribution ( Fig. 192 ) and phenology : Known from the middle part of Northern Bulgaria between Iskar River in West, Yantra River in East and the ridge of Stara Planina in South. Yet, the exact border between its populations and these of I. miksici is not clear, and the question whether both occur sympatrically and/or produce hybrids stays. The existence of intermediate forms possibly due to gene exchange by hybridisation between some taxa (e.g. in the I. rhodopensis complex and between I. longicaudata and I. modesta ) may also be expected here, especially regarding the neighbouring occurrence of I. plevnensis and I. miksici in the region of Iskar Gorge (W Stara Planina Mts). I. plevnensis inhabits mesophyte grass associations, mostly forest clearings or even rural areas in the lowland. It was found between 100 and 1200 m alt. Above this altitude in the Middle Stara Planina Mountains it is replaced by I. obtusa (both species have not been found together). Nymphs—(III–)IV–VI, imago—VI–VIII.