Bioacoustics of Australiagraecia helleri

Distribution. Common in suitable habitats across the southern coastal sand plain from Cape Pasely north to Moura, Western Australia ( Map 1 ) Habitat. A common inhabitant of typical Coastal Sand Plain heath. The katydids hide in the dense tangle of twigs and stems in dense heath during the day and emerge after dark to feed and mate. Seasonal occurrence. Adults of this species can be found from mid spring into mid-summer. Song. Song not recorded. Karyotype. 2n male = 31 ( 30t +Xt), Figs 22a D-E. Fig. 22a D Upper karyotype, lower left diakinesis, right first metaphase. Recognition. A. helleri is recognised in males by the combination of the elongate cercus curved apically ( Fig. 4C ) and the forked minute sclerites at the base of the phallic complex ( Fig. 4E ). Females have the subgenital plate about as long as broad and a gracefully upcurved and elongate ovipositor.

Differential diagnosis. Male. Antenna about 1.5 times the length of the body. Eye round, bulging, positioned very high on head. Hind tibia armed dorsally with numerous spines, alternating in lengths; apex with a pair of relatively delicate short spurs positioned subapically; ventral surface with a smaller number of longer spines on each side and with a single pair of much longer apical spurs. Prothorax with processes elongate, slender, rather closely set; meso- and metathoracic processes prominent, slanting. Tegmen short ( Table 1 ) stridulatory file positioned on raised swelling. Cercus ( Fig. 4C ) apically curved inwards, surface clothed with stiff, dark brown setae. Abdomen with tenth tergite soft, membranous, with shallow median impression; supra-anal plate ( Fig. 4B ) broadly triangular, with a few stiff setae and a median sulcus; paraprocts not well indicated ( Fig. 4B ); phallic complex ( Fig. 4E ) with forked rod at base. Subgenital plate about 1.5 times as long as broad; styles elongate, narrowly spaced, clothed with dark brown setae. Female. Differs from male in following. Cercus elongate, slender, not curving inwards, surface clothed with stiff, brown setae. Subgenital plate about as long as broad, apex with narrow, shallow median incision. Ovipositor very elongate ( Table 1 ), very gracefully upcurved. Colouration. Colour not different from A. spina . However, dorsal stripe becoming less intense apically ( Fig. 4B ). Cerci clothed with stiff, brown setae ( Fig. 4C ).