Pachytrachis tumidus, Ingrisch, Sigfrid & Pavićević, Dragan, 2010

Ingrisch, Sigfrid & Pavićević, Dragan, 2010, Seven new Tettigoniidae (Orthoptera) and a new Blattellidae (Blattodea) from the Durmitor area of Montenegro with notes on previously known taxa, Zootaxa 2565, pp. 1-41 : 34-38

Pachytrachis tumidus sp. n.

Figs. 17A–E , 18A–K , 19 E–F

Holotype (male): Montenegro: Durmitor, Komarnica Canyon, Krivača (= village of Komarnica), 950–1100 m, 9.VIII.1990, leg. D. Pavićević, in Coll. Zoologisches Forschungsmuseum Alexander Koenig Bonn ( ZFMK).

Paratypes: 1 Ƥ, same locality as holotype, 9.VIII.1990, leg. S. Ingrisch ( ZFMK); 1 Ƥ, do., 8.VIII.1989 (CI); 2 Ƥ, Montenegro, 40 km NW Nikšič, Krstac, 1000 m, 5.VIII.1968, leg. F. Willemse (CW).

Type locality. Montenegro, Durmitor, Komarnica Canyon, Krivača (= village of Komarnica), 950–1100 m.

Measurements. Body length male 19.5, female 16.5–26.0; pronotum length male 4.5, female 5.1–5.3; tegmen length male 3.1, female 1.8–2.0; hind femur male 17.8, female 19.0–20.5; ovipositor female 14.0– 14.5 mm.

Diagnosis. Females of the new species are similar to those of P. f r a t e r (Bunner, 1882). They differ by the ovipositor which is little but distinctly curved ventrad and by the shape of the subgenital plate. Males differ from all known species of Pachytrachis by the internal swelling of the cerci and by the compressed and widened apical parts of the titillators.

Description. Pronotum with disc convex, without median carina; completely rounded into paranota. Micropterous; tegmina of male reduced to stridulatory apparatus; tegmina of female reduced to scales, very little overlapping in middle ( Figs 17A–D ).

Male. Stridulatory file on underside of left tegmen curved, concave, with ca 75 moderately dense teeth ( Fig. 18A ). Mirror on right tegmen wider than long; hind margin rounded ( Fig. 17B ). Tenth abdominal tergite faintly furrowed in midline; rather short, hardly longer than ninth tergite; apical margin truncate in middle, faintly concave at both sides ( Fig. 18F ). Epiproct small; broadly rounded; with a circular pit at base. Cerci faintly curved at base, in dorsal view otherwise straight, in lateral view slightly sinuate; without tooth but with a distinct internal swelling behind basal third; before apex very faintly swollen ( Figs. 18E–F ). Subgenital plate with narrow median carina; apex roundly excised; styli thin.

Titillators separate; curved in middle; apical parts compressed, band-shaped, brownish hyaline; apex rounded; dorsal margin little convex and finely crenulated; basal parts dark brown; very base ovoid and brownish hyaline ( Figs. 18B–D ).

Female. Tenth abdominal tergite with central area little prolonged behind but angularly excised in middle. Epiproct triangular with a circular pit on top. Cerci thin, apex pointing. Subgenital plate with central area flattened, lateral areas with little concave surface; lateral margins converging; apex roundly excised; lobes on both sides of excision rounded or in a freeze-dried specimen subacute ( Figs. 18G–J ). Ovipositor with ventral margin little but distinctly concave; apex tapering ( Fig. 18K ).

Coloration. Dark brown with marmoration; sternites orange, yellowish or whitish brown. Frons brown marmorated ( Fig. 17E ). Vertex and pronotal disc with fine white median line, on vertex accompanied by a cuneate black spot on both sides. Two other fine white lines from bases of antennae along dorsal margin of eyes to occiput; on dorsal side bordered or not by a narrow black band, on ventral side bordered by a wide black post-ocular band. Pronotum with disc brown; paranota black with broad white ventral margin including a spot suffused with brown ( Figs. 17C–D ). Tegmina of male with disc dark brown, at apex with a white spot; lateral area blackish brown with a white spot at base ( Fig. 17A ). Tegmina of female with hidden part brownish white; exposed part blackish brown with internal and posterior margin on internal side white ( Fig. 17C ). Abdominal tergites dark brown; first three abdominal tergites with black lateral bands bordered by white bands on dorsal and ventral sides. Legs brown with blackish brown spots; hind femur with little distinct fishbone pattern.

Etymology. Named for the internal swelling on the male cercus; from Latin tumid = swollen. Distribution. Mountains of western Montenegro, possibly extending into Bosna.

Stridulation ( Fig. 19 ): The single male collected produced echemes with 3–4 syllables. In contrast, males of Pachytrachis frater collected near the Adriatic coast produced monosyllabic songs Heller (1988). In the new species, the echemes are repeated at intervals of 1–4 s. Stridulation is mainly in the ultrasonic range with a maximum at about 30 kHz (determined by an ultrasonic detector).

Figures

FIGURE 19. Oscillograms for comparison of calling songs of Pachytrachis species: A – B, P. gracilis (Brunner, 1861); C – D, P. striolatu s (Fieber, 1853); E – F, P. t u m id u s sp. n. — A, C, E, series of syllables; B, D, F, one syllable in higher time resolution.

FIGURE 17. A – E, Pachytrachis tumidus sp. n. from Krivaċa (A – B male holotype; C – E, female paratype); F – G Pachytrachis frater (Brunner, 1882) female from Moraċa valley, Montenegro (CW). – A, male left tegmen; B, right tegmen; C, female head pronotum and wings in dorsal view; D, G, do. lateral view; E – F, female face.

FIGURE 18. A – K, Pachytrachis tumidus sp. n., (A – F, male holotype; G – H, female paratype freeze-dried; I – K, female paratype air-dried); L – N, Pachytrachis frater (Brunner, 1882) female from Moraċa valley (CW). – A, stridulatory file; B – D, titillators in different magnification (B, oblique lateral view; C, dorsal view; D, do. with baso-lateral sclerites); E, male abdominal apex with cerci in lateral view; F, do. in dorsal view; G, I, M, female subgenital plate in ventral view; H, J, L, do. in lateral view; K, N, ovipositor.