Bioacoustics of Poecilimon elegans

Distribution. The range of P. elegans in the newly defined sense is restricted to areas near the northern Adriatic coast in north-eastern Italy , Slovenia and Croatia , with the southernmost locality near Pula. Stridulation . Stridulation of P. elegans has been described by Heller (1988) as consisting of single syllables repeated in longer intervals. His recordings refer to a male from the Lovćen Pass near Kotor in Montenegro . Observations with males from Trieste gave quite different results. Stridulation is a syllable train, but the males switch from time to time from repeating syllables of a type A to repeating those of a type B and reverse. Syllables of type A consist of a very quiet initial string of a few pulses that was completely lacking in one of three males studied. It is followed by three loud separate pulses ( Fig. 16 A). The third of these three pulses is the less loudest and the interval between the second and the third pulse is little longer than between the first and the second. When the males change to syllables of type B, the initial string of dense pulses becomes louder with increasing loudness. It was then audible in all three males. The string is followed by three or four loud separate pulses and another pulse after a short interval. Intermediate syllables can be produced during switching between both song types . Syllable repetition rate for both types is about 3–4 syllables per second at 24.5–25°C. Longer pauses occurred occasionally. Sound intensity was highest between 40–45 kHz.

Measurements. Pronotum male 4.3–5.4, female 4.6–5.2; tegmen male 0.5–2.3, female 0.0–1.0; postfemur male 14.4–17.0, female 15.8–17.8; ovipositor 7.7–9.0 mm. Re-description. Male. Scapus 1.1–1.5 (mean 1.26) x broader than fastigium verticis. Fastigium verticis slightly widened in front or with subparallel lateral margins, furrowed dorsally. Discus of pronotum markedly rounded, faintly raised in metazona or with almost straight dorsal margin; apex distinctly concave; ventral margin of paranota faintly concave to substraight in front, rounded behind ( Figs. 13 A–B). Micropterous. Stridulatory file ( Fig. 15 B) with 46–74 teeth divided by 2 distinct steps in 19–31 very small basic, 7–14 large median, and 18–41 small apical teeth; of the basic teeth 4–7 can be found on the basic step and of the apical teeth 0–3 on the apical step. Cerci gradually narrowing from base to about apical third, strongly curved mediad in or behind apical third, slightly flattened before apex and continuously narrowed into the apical tooth ( Fig. 13 D). Subgenital plate curved and narrowing behind middle; narrow apical part ± parallel sided; apex slightly to distinctly excised with lateral lobes rounded ( Fig. 13 C). Female. Scapus 1.0–1.5 (mean 1.20) x broader than fastigium verticis. Fastigium verticis slightly widened in front or with subparallel lateral margins, furrowed dorsally. Discus of pronotum markedly rounded; apex slightly to distinctly concave; dorsal margin in lateral view substraight ( Fig. 13 E); ventral margin of paranota very faintly concave or straight in front, rounded behind. Squamipterous, tegmina almost completely hidden. Cerci conical. Subgenital plate triangular, comparatively narrow, apex almost pointed ( Fig. 13 F). Ovipositor sabre shaped, apical quarter dentate; without nodule above basal fold ( Fig. 13 G). Coloration. Male. Green with black stipples. Pronotum with white lateral bands and white ventral margins. Tegmina yellowish, speculum of discus (between cu1b and cu2 or also between cu1a and cu1b) and a spot at the hind margin black or dark brown. Abdominal tergites green with white lateral bands bordered externally by a black line, and a median dark green band interrupted by a light green line. Coloration usually less distinct or lacking on apical tergites, sometimes only indicated in basal half of abdomen. Female. Green with black stipples. Pronotum with white lateral bands, usually extended on the first 2 – 3 abdominal tergites only, rarely (1 Ƥ) beyond middle of abdomen. Tegmina yellowish with a black dot at hind margin.