Bioacoustics of Pyropsalta rhythmica

Measurements . Range and mean (in mm) for 10 males , 10 females (includes smallest and largest available specimens). Length of body (including head): male 16.3–21.5 (19.7); female (including ovipositor) 19.3–26.5 (21.9). Length of forewing : male 18.1–28.0 (24.3); female 22.8–30.9 (26.3). Width of head (including eyes): male 5.0–7.0 (6.3); female 6.2–7.5 (6.8). Width of pronotum (across lateral angles): male 5.4–7.9 (6.8); female 6.2–7.9 (7.1). Distinguishing features . Males of Pyropsalta rhythmica sp. n. are difficult to separate from those of P. amnica sp. n. and are best distinguished by the black markings on tergites 5–7. In P. rhythmica these are either entirely black or if partly orange then the black always bisects the orange along the dorsal midline of each segment; in P. amnica all these segments are partly or entirely orange and are never completely bisected by black on any segment. Further, sternites III and IV in P. rhythmica nearly always have distinct areas of black centrally, these missing in P. amnica . Females can be distinguished by the length of the ovipositor sheath. In P. rhythmica the ovipositor sheath protrudes no more than 1 mm beyond the dorsal beak but in P. amnica it protrudes close to 2 mm . Song ( Figs 58a–c ). Song recordings were obtained from the WAU.SSD, WAU.BOY, and WAU.MAN paratype locations plus the following sites: S. of Serpentine ( 32º31.400’S 115º58.244’E ); N. of Boyup Brook ( 33º48.391’S 116º26.742’E ); N. of Bunbury (WA.GCC, 33º20.237’S 115º40.784’E ), Brunswick Junction ( 33º15.108’S 115º50.456’E ), Pinjarra ( 32º38.413’S 115º52.12’E ), Porongurup National Park (WA.PNP, 34º40.539’S 117º52.266’E ), and Manjimup ( 34º14.094’S 116º8.546’E ). Because males usually sang from high stations, often out of sight of the recordist, we recorded only uncollected males. However, one male was captured singing on the ground near a mercury vapour light trap, so we are confident that the song below is produced by P. rhythmica . This is the first Pyropsalta song to be described. Males sing a continuous song consisting of a train of extremely resonant clicks produced at about 6–8 per second. The clicks are very sharp, with most of the sound energy contained within a single pulse around 1–2.5 ms long. Measuring this parameter was difficult because males in close proximity synchronize their songs with remarkable precision, such that it is sometimes difficult to distinguish the song of a nearby focal male from the background of conspecifics. Most sound energy is concentrated in the range 6–10.5 kHz, with a peak intensity around 8–9.6 kHz. There is no frequency modulation. A few recordings suggest that males skip one pulse occasionally while remaining in synch with the chorus. This is a possible mechanism by which the male might cue replies from receptive females, but additional confirmation is needed.

Etymology. From the Greek derived Latin adjective rhythmicus meaning regular recurring motion or measure and referring to the rhythmical quality of the song. Types . Holotype male (Simon Lab. voucher 02.AU.WAU.SSD.01), S of South Dandalup , Western Australia , 32°36’S 115°55’E , 23m , 31.xii.2002 , Marshall , Moulds , Hill & Vanderpool ( WAME 113485 ) ( WAM ) . Paratypes as follows: WESTERN AUSTRALIA : 2 males , 2 females , WAU .MAN, jctn of Graphite & Ralston Rds, 3 km NW of Manjimup , 3.i.2003 , 34°13’S 116°08’E , 274 m , Moulds , Marshall , Hill , & Vanderpool ( AMS ). 2 males , Brunswick Junctn. , Perth , 13.i.1994 , D. Emery ; 31 males 8 females , Canning R . & RL4 (jnctn), Kelmscott , 1.xii.97, D. Emery (emerging on grass 0530h) ; 3 females , Dwellingup, M. R . Williams & K. Whitford , 2.i.93 ; 1 male , Gosnells , Perth, M. R . Williams & D. Emery , 2.xii.1997 ; 2 males , 2 females , Albany H’way, 25 km S Armadale , 27.xi.2013 , A. Mitchell ; 1 male , 1 female , Routes Rd. , Lesmurdie , 32°00’56”S 116°13’32”E , 5.i.2013 , A. Mitchell ( DE ). 2 males , S of South Dandalup , 32°36’S 115°55’E , 23m , 31.xii.2002 , Marshall , Moulds , Hill & Vanderpool ; 2 males , 2 females , Donnybrook , 13.xii.1985 , M.S. & B.J. Moulds ; 1 male , 1 female , Canning R . & RL4 (jnctn), Kelmscott , 1.xii.97, D. Emery ( LP ). 13 males , 1 female , S of South Dandalup , 32°36’S 115°55’E , 23m , 31.xii.2002 , Marshall , Moulds , Hill & Vanderpool ; 4 males , 1 female , WAU . BOY , nr Boyup Brook , 210 m , 33°48’S 116°27’E , 5.i.2003 , Marshall , Moulds , Hill & Vanderpool ; 2 males , 1 female , AU. WA .BJP, Bridgetown , Jarrah Pk , off Brockman Hwy , 2.i.2003 , 34.029[º]S, 115.984[º]E. 300 m , Hill , Marshall , Moulds , Vanderpool ; 1 male , 1 female (in copula), WAU . MGR, Margaret River , 85 m , 33:57S 115:04E, 2.i.2003 , Marshall , Moulds , Hill & Vanderpool ; 5 males , WAU . HWK, jctn of Old Vasse Rd. & Hawke Rd , nr Pemberton , 200 m , 34°29’S 115°57’E , 4.i.2003 , Moulds , Hill , Marshall & Vanderpool ; 8 males , 8 females , WAU . PMB , Pemberton , 126 m , 34°27’S 116°02’E , 3.i.2003 , Moulds , Marshall , Hill , & Vanderpool ; 24 males (1 genitalia prep. PYR 1 ), 9 females , WAU .MAN, jctn of Graphite & Ralston Rds, 3 km NW of Manjimup , 34°13’S 116°08’E , 274 m , 3.i.2003 , Moulds , Marshall , Hill , & Vanderpool ; 42 males , 26 females , Donnybrook , 13.xii.1985 , M.S. & B.J. Moulds ; 2 males , Collie , 11.xii.1985 , M.S. & B.J. Moulds ; 1 male (genitalia prep. CI 4 ), Collie , 4.i.1991 , M.S. & B.J. Moulds ; 10 males , 6 females , Harvey , 4.ii.1991 , M.S. & B.J. Moulds ; 1 males , Dwellingup , 8.i.1991 , M.S. & B.J. Moulds ; 1 male , 1 female , Kent River , 10 km E of Bow Bridge , 16.i,1991, M.S. & B.J. Moulds ; 1 male , Augusta , 20.i,1985, S. Lamond ; 4 males , 2 females , Pinjarra , 9.i.1991 , M.S. & B.J. Moulds ; 1 male , Pinjarra , xii.1990 , A. Johnson ; 4 females , Wilga , 22.xii.1986 , K. & E. Carnaby ; 6 males , 4 females , Pemberton , 14.i.1991 , M.S. & B.J. Moulds ; 2 males , 1 female , Warren River Western Hwy , nr Pemberton , 14.i.1991 , M.S. & B.J. Moulds ; 24 males (2 genitalia preps CI 3, PRY 3 ), 6 females , Roelands E of Bunbury , 4.i.1991 , M.S. & B.J. Moulds ; 2 males , Brookton Hwy , 7 km SE Kelscott , 19.xii.2014 , P. Hutchinson ; 5 males , 7 females , Albany Hwy , 25 km S Armadale , 28.xii.2012 , 21.i.2012 , 21,29. xii.2014 , P. Hutchinson ; 2 males , 1 female , Gleneagle S.F ., S of Armadale , 2,15. xii.2011 , P. Hutchinson & P. Kay ( MSM ). 6 males , Brookton Hwy , 7 km SE Kelmscott , 19.xii.2014 , P. Hutchinson , to mv light, PMH Coll #CIC 1796, 1797, 1842, 1822, 1823, 1884 ; 1 male , 1 female , Brookton Hwy , 26 km SE Kelmscott , 15.xii.2017 , P. Hutchinson , to mv light, PMH Coll #CIC 1804, 1805 ; 1 male , 2 females , Brookton Hwy , 50 km SE Kelmscott , 14.xi.2015 , P. Hutchinson , to mv light, PMH Coll #CIC 1803, 1806, 1807 ; 1 male , Albany Hwy , 7 km S Armadale , 11.xii.2014 , P. Hutchinson , to light, PMH Coll #CIC 1824 ; 24 males , 2 females , Albany Hwy , 25 km S Armadale , 30.xii.2011 , 28.xii.2012 , 6,21. i.2012 , 27.xi.2013 , 5.xii.2013 , 11,29. xii.2014 , 18.i.2014 , P. Hutchinson , to mv light, PMH Coll #CIC 1798, 1800, 1801, 1802, 1809, 1811, 1813, 1815, 1816, 1819, 1820, 1821, 1827, 1828, 1830, 1829, 1843, 1846, 1851, 1854, 1856, 1855, 1872, 1880, 1881, 1882 ; 7 males , Albany Hwy , 25 km S Armadale , 28.xii.2011 , 21,26. xii.2014 , P. Kay , to mv light, PMH Coll #CIC 1799, 1812, 1857, 1859, 1883, 1875, 1873 ; 1 female , Ashendon , 10 km S Mt Dale , 6.ii.2014 , P. Kay , to mv light, PMH Coll #CIC 1808 ; 1 female , Red Hill Res ., E of Midland, Perth , 12, xi.2000 , P. Hutchinson , on Allocasuarina hugeliana, PMH Coll #CIC 1810 ; 1 male , 1 female , Beckenham, Perth, 5.xii.2011 , 31.i.2015 , P. Hutchinson , to uv light, PMH Coll #CIC 1814, 1869 ; 2 males , Scarp Rd, Dwellingup, 29.xii.2020 , P. Kay , to light, PMH Coll #CIC 1818, 1847 ; 1 male , Glen Mervyn, 25 km S Collie , 26.xii.2011 , P. Kay , to mv light, PMH Coll #CIC 1950 ; 2 females , Mt Chudarup , N Windy Harbour, 6.i.2010 , P. Hutchinson , to light. // PMH Coll #CIC 1848, 1849 ; 5 males , Churchman’s Brook Dam, S Armadale , 15,18. i.2012 , P. Kay , to mv light, PMH Coll #CIC 1879, 1877, 1860, 1876, 1878 ; 4 males , Gleneagle SF , [ 25 km ] S of Armadale , 15.xii.2011 , P. Hutchinson & P. Kay , to mv light, PMH Coll #CIC 1861, 1864, 1865, 1868 ( PH ). 18 males , 9 females , WAU .MAN, jctn of Graphite & Ralston Rds, 3 km NW of Manjimup , 3.i.2003 , 34:13S 116:08E, 274 m , Moulds , Marshall , Hill , & Vanderpool ( WAME 113486-113512 ) ; 4 males , 4 females , WAU . PMB , Pemberton , 126 m , 34:27S 116:02E, 3.i.2003 , Moulds , Marshall , Hill , & Vanderpool ( WAME 113513-113520 ) ( WAM ).