Bioacoustics of Gryllacris (Gryllacris) signifera

Description. Medium sized species. Head: Face narrow ovoid; fastigium verticis about as wide as scapus; ocelli little distinct; fastigium frontis separated from fastigium verticis by a faint suture interrupted in middle; subocular furrows only indicated as a weak depression above bases of mandibles ( Fig. 12E ). Abdominal tergites two and three with minute stridulatory pegs (4, 6–9; 5–7, 11–12; n = 2 females ). Wings surpassing hind knees ( Fig. 10 E–F). Tegmen: Radius with two branches, both forked near tip; media anterior fused in basal area with radius (in the male from Batavia RS branches from MA not from R); media posterior absent; cubitus anterior forks between basal third and mid-length into two veins, CuA1 and CuA2; cubitus posterior undivided, free throughout; with 4 anal veins. Legs: Fore coxa with a large spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with four pairs of large ventral spines and one pair of ventral spurs ( Fig. 2C ); hind femur with 6–8 external and 8–11 internal spines on ventral margins; hind tibia with spaced spines on both dorsal margins, ventral margins with one preapical spine each; with 3 apical spurs on both sides. Coloration. General color light brown ( Figs. 102 D–E); disc of pronotum adorned with black hieroglyphic figure (roughly composed of 4 sinuate or curved long lateral dark bands and a short straight medial band together with some small spots), posterior margin with rim dark brown. Vertex with a round black spot in middle and black bands on both sides. Legs light brown. Face medium brown with some indistinct lighter spots; antennal scrobae dark. Tegmen yellowish transparent, veins yellow to pale brown; hind wing along anterior margin yellowish transparent, otherwise ochre transparent, main veins brown; cross veins blackish brown adorned by a narrow brown band on both sides. Male. Eighth abdominal tergite strongly prolonged behind. Ninth abdominal tergite ( type F in Brunner 1888 ) wide at base; dorsal apical margin prolonged into a short and narrow, setose projection with bifid tip; in about middle of projection with a few tubercles ( Figs. 13 J–M). Underside of ninth tergite prolonged proximad, finally curved down and at bottom posteriorly and ends in a broad subtruncate tip with slight medial incision and short lateral cones. Subgenital plate about twice as wide as long; lateral margins straight, little diverging; apical margin wide-triangular but in middle little excised and on both sides of excision obtusely swollen; slightly curved styli inserted at lateral angles. Phallus membranous. Female. Seventh abdominal sternite little wider than preceding sternites; otherwise normal. Subgenital plate rather long; wide at base with strongly converging lateral margins, constricted behind basal third, afterwards with convex lateral margins, apex slightly bi-lobate; area along lateral and apical margins elevated and in apical area little swollen; baso-central area occupied by a large groove that holds in about middle of subgenital plate a narrow elongate process with bifid apex, base of subgenital plate membranous with outlined triangular groove in middle ( Figs. 16 A–B). Ovipositor elongate but curved throughout, with faintly approaching margins; before tip dorsal margin with a slight expansion ( Fig. 17E ). Measurements ( 2 males , 2 females ).—body w/wings: male 34–38, female 36–38; body w/o wings: male 22– 32, female 28–32; pronotum: male 6.0–6.5, female 6.5; tegmen: male 25–27, female 23.5–25.0; tegmen width: male 10, female 9; hind femur: male 15–19, female 17; antenna: male 70–130, female 130; ovipositor: female 17– 18 mm .