(Figs 8A-E; Table 1, Map 3)
8 The specific name refers to the structure of the male cercus.
Common name. Wavy-tailed Katydid
Holotype male. (In alcohol). 1” 31 o 20’S 118 o 30’E (GPS) W.A. Carrabin, Great Eastern Highway 9 November 1999 DCF Rentz, YN Su Stop 181”. 2. “ ANIC database #14008748”. Holotype in Australian National Insect Collection, Canberra. Specimens examined. Paratypes. Western Australia. 28 o 00’S 119 o 57’E (GPS) Nr Willow Well, 20 km N by E of Flat-Topped Hill, 22.x.1995 (DCF Rentz, PJ Greenslade, Stop 126, 1 male, DCF Rentz, Cytol. prep. 95-75, ANIC). 29 o 16’S. 117 o 37’E. Paynes Find, 7.5 km S. on Great Northern Highway. 8.xi.1999 (DCF Rentz, YN Su, Stop 170, 2 males, one collected as nymph, matured in laboratory 12.xii.1999, 1 female, (body decomposed), ANIC).
Type locality. The type locality was a patch of natural vegetation along the Great Northern Highway. The holotype was collected at night stridulating on top of a dried Triodia culm.
Measurements. Table 1.
Differential diagnosis. Male Size relatively large for genus, form robust (Table 1). Antenna slightly longer than length of body, not annulate. Eye faintly cordate, not especially bulging. Fore tibia unarmed dorsally, middle tibia with 2 widely spaced spines positioned at extremes of proximal one-third on posterior margin. Hind femur armed on internal margin of ventral surface with 6 small spines positioned along entire length; tibia armed dorsally with 2 apical spurs, ventral surface with a pair of slightly larger apical spurs. Prothorax with a pair of very small widely separated, tubercle-like processes; meso- and metathorax each with a pair of much larger peg-like processes. Tegmen mostly exposed (Figs 8B, E), stridulatory file on a blister or swelling. Cercus distinctive (Fig. 8A) positioned horizontally, elongate, undulating, apically recurved. Abdomen with tenth tergite bearing a distinct U- to V-shaped median incision (Fig. 8A); supra-anal plate with a shallow median incision; paraprocts hardly visible (Fig. 8A); phallic complex simple, median portion with a minute tuberculate “tongue” with a minute forked sclerotised basal process. Subgenital plate about as broad as long, styles short, robust (Fig. 8D), median incision shallow, broadly V-shaped.
Female Known from fragments of a captive female topotype that laid eggs and gradually decomposed.
Colouration. Overall colour straw brown, with typical median longitudinal stripe (Figs. 8B, C). Male tegmen with dark line on internal margin.
Distribution. Known from a few inland localities (Map 3).
Habitat. A. curvata was associated with Triodia at several of the localities where it was collected.
Seasonal occurrence. A. curvata matures in late spring and probably survives well into summer. This species occurs as adults in late spring and summer.
Song. The song was not recorded but sounded like a continuous tapping, similar in some respects to that of the zaprochiline species of Kawanaphila. Singing individuals were very wary and sensitive to the light of a torch. The singing male dropped into the Triodia patch at the slightest disturbance.
Karyotype. Not seen.
Recognition. Recognised by its relatively large size (Table 1). Males are distinctive in the shape of the cercus (Fig. 8A) which is undulating; the phallus seems relatively simple with a central tongue-like portion that is minutely tuberculate. There is a minute forked process at the base of the phallus. Females not well represented in these samples.
Discussion. A. curvata is a member of the Murchison in the Austin Botanical District and Wheatbelt Region as defined by Beard (1990). The type locality receives about 200 mm of rain a year. It would be interesting to see if this species strays into the adjacent Mallee Region which receives about twice as much rain as the Austin District and has a much more luxuriant flora. This species seems to be associated with Triodia. During the day individuals hide within the patches of the plants affording protection from predators and the weather.