Ornebius Guerin-Meneville 1844

Identification of Ornebius Guérin-Méneville, 1844 by sound Ornebius sound recordings taken in Auckland, Coromandel, Waikato and in New Plymouth yield a song with a peak frequency between 4.5 and 5.6 kHz. Chirps are approximately one second apart and consist of three pulses; a single pulse followed by a pause of 0.3 seconds then two more pulses close together (Fig. 34). This song matches that of Ornebius aperta (Otte & Alexander 1983: fig. 314; Gwynne et al. 1988). As previously observed by Ramsay (1990, 1991), the paraprocts are also a good match for Ornebius aperta, club-like in shape, narrowest at the base and widest one fifth of the length from the apex (Fig. 33G–I). Ornebius crickets around Whangārei and Kerikeri in Northland sing at a peak frequency of 4 kHz (T = 23°C). Chirps are approximately two seconds apart and consist of four to five pulses; a single pulse followed by a pause longer than half a second then three to four pulses close together (Fig. 35). This song does not match any known species of Ornebius. The male paraprocts are subtly different from those of O. aperta, with a longer narrow neck at the base, and the widest point one fourth of the length from the apex (Fig. 33K). While this shape may resemble more closely the paraprocts of Ornebius wandella Otte & Alexander, 1983, the latter species has two very prominent hair tufts projecting backwards from the posterior margin of the suranal plate (Otte & Alexander 1983: fig. 312y); these are missing in Ornebius aperta and in Ornebius crickets from Northland (Fig. 33D–E). Except for the subtle difference in the shape of the male paraprocts, male and female Ornebius crickets from Northland cannot be differentiated from Ornebius aperta by morphology. Based on this information, Ornebius crickets from Northland might be a species other than Ornebius aperta, but I am not confident enough to state that they definitely are, let alone to designate a new species. This really needs to be done in the context of a comprehensive revision of Ornebius from the east coast of Australia and from the wider Pacific region, based on morphology, song and molecular data. I will therefore refer to the Ornebius population in Northland as Ornebius aff. aperta Otte & Alexander, 1983, where the abbreviation ‘aff.’ is used as suggested by Sigovini et al. (2016). The boundary between the Auckland and Northland Ornebius populations is unknown.