Bioacoustics of Xeropsalta rattrayi

Etymology: Named after Ian Rattray who was instrumental in discovering this species. Distinguishing the Xeropsalta species ( Figs. 2 to 8). Xeropsalta rattrayi n. sp. males are readily distinguished from males of the other species by their green colouration (or yellow-green in aged specimens). The X. aridula n. sp. and X. rattrayi n. sp. females, however, are superficially similar, but X. rattrayi have narrower tapering abdomens and X. aridula n. sp. narrower fore wings. The females of X. thomsoni are readily distinguished by pale yellow-brown colour and the dark narrow fascia along the dorsal length of abdomen. The morphological and colour separation of the males of X. aridula n. sp. and X. thomsoni n. sp. can sometimes be problematic, although not so for the X. thomsoni n. sp. specimens from the more southerly locations. The abdominal dorsal darker patterns are, however, typically more sharply defined in X. thomsoni n. sp. ; the coloration of X. aridula n. sp. is commonly paler than seen on X. thomsoni n. sp. . Figs. 3C–E indicate that opercula shapes do differ slightly, those of X. thomsoni n. sp. slightly less elongated and less domed medially, while Figs. 6C–E and 7C–E indicate small, but possibly significant differences in the profiles of the median lobes of the uncus and in the sizes and shapes of the pygofer basal lobes, as seen in lateral and ventral views. The X. ratttrayi n. sp. males are readily distinguished by the green to yellowish green colour and dark dorsal fascia along tergites. The abdominal colouration of X. festiva n. comb. (Pl. 8) is readily distinguished from the other species of Xeropsalta n. gen. Popple ( 2014–2017 ) provides significant additional data on X. festiva n. comb. (previously named Mugadina festiva ). As shown below, the calling song differences of all four species are clearly diagnostic.