Bioacoustics of Chauliogryllacris acaropenates

Description. Male. Size moderate to large for genus, form robust ( Table 1 ). Head very large ( Fig. 2A ) protruding well in front of pronotum ( Fig. 1A, D ). Fastigium of vertex very broad more than 5x as broad as antennal scape, margins not carinate or raised ( Fig. 2A ); antennal scape elongate, about ¾ length of eye, pedicel short, stout, about 1/3 length of scape, flagellum 3–5 times length of body when intact. Frons sculptured, punctate ( Fig. 2A ), the punctures irregular in shape, swollen below eye (belying large mandibles beneath; median ocellus relatively small ( Fig. 2A ), about half the width of the antennal scape, lateral ocelli similarly small but very elongate. Eye elongate, narrow. Ventral surface of thorax unmodified ( Fig. 2E ). Fore tibia unarmed dorsally ( Fig. 2C ), ventral surface with 5 spines on each margin, in lateral profile slightly swollen. Middle tibia unarmed dorsally, ventral surface with 5 spines on each margin. Hind tibia armed dorsally with 4 stout teeth on each margin positioned in apical half ( Fig. 2B ); ventral surface unarmed except apex with a single elongate spine on each side of dorsal surface, ventral surface with 4 apical spurs, each preceded by a single elongate spine, slightly shorter than the length of one of the spurs. Fore and middle femora unarmed; hind femur armed on ventral surface with 6 stout teeth on inner margin increasing in size to apex ( Fig. 2D ), external margin with 1, 2 teeth but with a single apical spine; stridulatory area a single arched line of pegs ( Fig. 3B ). Pronotum with deep furrows on surface ( Fig. 1A, D ), “Z”-shaped on each side; anterior margin evenly convex, caudal margin truncate, humeral angles distinct, indented; lateral lobe shallow, ventral margin truncate, rimmed. Abdomen normal in shape for Gryllacrididae . Stridulatory teeth laterally on tergites 2, 3 ( Fig. 3A ). Tenth tergite domed, apically indented, lateral angles acute ( Figs. 4A, B ); subgenital plate ( Fig. 4C ) dorsally with median flanges medially carinate, lateral flanges subconical with a small external tooth at base ( Fig. 4A ). “Paraprocts” heavy, strongly divergent, well hidden beneath tenth tergite; cercus gracefully elongate, curved upward ( Figs. 4A, B, E ). Concealed genitalia with phallus protruding, covered with stout setae ( Fig. 4D ). Female. Differs from male in following characters: size much larger, head much more pronounced, mandibles much more developed. Subgenital plate ( Fig. 4F ) massive, lateral prongs parallel. Ovipositor straight, shorter than length of body. Pronotum ( Fig. 1A ), abdomen ( Fig. 1D ), ovipositor elongate, not thickened or modified apically. Tegmina and wing venation ( Fig. 5 ). Generally speaking, the forewing venation pattern of Chauliogryllacris acaropenates sp. nov. corresponds to that represented on fig. 13A, G in Béthoux (2012) . Specifically, MP+CuA (emerging from M+CuA) has a distinct free part (but of variable extent), and CuA+CuPaα is simple. The later state characterizes the ‘ Etagryllacris type’. In general appearance, forewings of Chauliogryllacris acaropenates sp. nov. resemble those represented on Fig. 16A, B in Béthoux (2012) . Note, however, that the corresponding wings were selected because they displayed unusual venation patterns. The occurrence of secondary intercalary veins is not extensively documented in hind wings of gryllacridids. Referring to cases documented in Béthoux (2012) , the occurrence of secondary intercalary veins of 2nd order, as in Cha”uliogryllacris acaropenates , is unique, but might prove more widely distributed. Colour. Overall colour of body reddish dark brown in life ( Figs 1A, B ). Head black, this colour extending onto dorsal ¼ of clypeus, remainder of clypeus and labrum straw brown in life.