Isophya speciosa (Frivaldszky, 1867)

(Figs 30, 55, 79, 104, 129, 181, 190, 195)

Odontura speciosa (Frivaldszky): Frivaldszky 1867 (sp.n.). Isophya tenuicerca Ramme: Ramme 1951 (sp.n.).

Morphological description: see the references above; Brunner von Wattenwyl 1878; Brunner von Wattenwyl 1882; Eliescu 1936; Ramme 1951 (both as I. speciosa and I. tenuicerca); Bey-Bienko 1954; Can 1959a, b (as I. tenuicerca); Harz 1969; Heller 1988. Bioacoustics: Heller 1988. Karyotype: Warchałowska-Śliwa et al. 2008.

The species is well characterised in the cited references. Slight variation is observed in the shape of the apex of male cerci which generally coincides with the differences between I. speciosa and I. tenuicerca.

Diagnosis: I. speciosa differs from I. amplipennis by the slender male cerci with narrow apex and pointed apical/subapical tooth (Figs 104, 181 B); female lamella (Fig. 129) is less laterally protruded; male stridulatory file (Fig. 181 A) bears the largest number of teeth among the known representatives of the group—from 154–160 (in two males from NE Bulgaria, Byala, and SE Bulgaria, Kovach, respectively) to over 170 (Heller 1988) and has a length of 2.6–2.8 mm (present paper: two males from NE and SE Bulgaria, respectively) or possibly more. Male song (Fig. 190) has four recognisable parts. The syllables are longer than these of the other studied species of the group (about 3.6 s at>27°С after Heller 1988 and 5.2 s at 24°С in a male studied here); possibly there are differences in the impulse interval and length of different parts of the song between I. speciosa and I. amplipennis but it is difficult to judge for this character due to the significant differences in the recording temperature of available recordings (compare Heller 1988: Abb. 33 for both species as well as this paper: Fig. 190).

Distribution (Fig. 195) and phenology: Subendemic for the Balkan Peninsula, known from S Romania, Serbia, Kosovo, Bosnia and Hercegovina, Macedonia, Bulgaria, NE Greece (Thraki), Eropean Turkey and NW Anatolia. This is the widestly distributed Isophya on the Balkans, inhabiting mesophyte plant associations from the sea coast up to 2500 m altitude in Pirin Mts (Bulgaria). Due to its wide altitudinal range the phenology of some populations may be largely shifted, i.e. in the highest places nymphs emerge when imagines disappear in lowlands. Nymphs— ІІ(VI)–V(VІІ), imago—IV(VІІI)–VІІ(ІХ).

Notes to the literature data: We partially refer the data by Nedelkov (1908) for I. pyrenaea to I. speciosa basing on one male from Dragalevtsi, identified by Nedelkov as I. camptoxypha (Fieb.). However, the locality “Vitosha” has also been tentatively referred to I. rectipennis following Chobanov (2009b).

Köhler (1988) recorded I. brevipennis Br.W. (synonym of I. camptoxypha (Fieber)) from Pirin based on a single female. The specimen by Köhler (1988) most probably belongs to I. speciosa, occurring at that height on Pirin Mts together with I. bureschi. However, I. bureschi is more similar to I. modestior, the latter also wrongly recorded by Köhler (1988) from Pirin.