Arenopsaltria nubivena (Walker)

Ewart, Anthony, Moulds, Max S. & Marshall, David C., 2015, Arenopsaltria nubivena (Cicadidae: Cicadinae: Cryptotympanini) from the Arid Regions of Central Australia and Southwest Western Australia, Records of the Australian Museum 67 (6), pp. 163-183 : 164-173

Arenopsaltria nubivena (Walker)

Figs 1–9

Description. Male: Figs 1 , 3A , 4 .

Head. Width across compound eyes slightly less than across lateral margins of pronotum (excluding lateral angle of pronotal collar) and wider than mesonotum; vertex distinctly wider than supra-antennal plate, forming a broad and conspicuous extension to eyes; the eyes thus form the termination of the vertex, appearing as on a broad stalk extended away from the head when examined in dorsal view; vertex and frons pale to medium brown, slightly darker medially; supra-antennal plate pale brown; ocelli pale red; length between lateral ocelli much less than between ocelli and eyes; postclypeus somewhat bulbous in anterior view, flattened in dorsal view, and gently rounded in lateral profile, pale brown, slightly darker along transverse ridges; head and the transverse ridges of postclypeus covered with very short golden pubescence; anteclypeus pale brown, covered by short golden pubescence laterally; rostrum brown, darker apically, reaching hind coxae; gena and mandibular plate pale brown, covered by short golden pubescence; antennae dark brown.

Thorax. Pronotum: width at dorsal midline much less than diameter of eyes; paranota slightly ampliate, becoming strongly ampliate on lateral angle of pronotal collar; paranota showing slight but distinct serration, no mid lateral tooth; conspicuous broad sandy-brown central fascia, broadest at anterior and posterior termination, with narrow black margin that partially extends along paramedian fissures; remaining pronotal colouration pale brown, with small black spots on the anterior part of the lateral fissures. Mesonotum: submedian sigilla variably deep brown, grading to paler brown medially, bordered by prominent black to deep brown parapsidal sutures; lateral sigilla dark brown, not sharply defined, grading into the generally paler brown of the enclosing mesonotum; cruciform elevation wider than long, pale brown, slightly darker along anterior arms; areas between lateral cruciform elevation arms dark brown to black, grading into scutal depressions, these areas covered by prominent white pubescence; epimeral lobe reaching operculum; surface of mesonotum uneven; ridges between wing grooves sandy brown, black within grooves; metanotum concealed on dorsal midline.

Wings ( Fig. 1A ). Fore wing: Hyaline, with 8, very rarerly 7, apical cells; no subapical cells; ulnar cells longer than apical cells, with ulnar cell 3 angled to radial cell; radial cell shorter than ulnar cells; basal cell broad, mostly filled by brown infuscation; height of costal vein comparable to R+Sc vein; costal plus R+Sc veins almost parallel to node; pterostigma present and darkly infuscated especially along anterior margin; vein CuA very weakly bowed to cubital cell, with the medial cell of similar width, although larger in area; cubital cell occasionally divided by an extra vein; veins M and CuA widely separated at their intersection with basal cell; vein RA 1 almost parallel to Sc for its length; vein CuA 1 divided by crossvein m-cu, with both segments of similar length; veins CuP and 1A fused for most of their lengths; very distinctive areas of dark black to brown infuscation overlying veins at bases of apical cells 2–6, weakly on and around apical cell 1, also adjacent to the ambient veins, in part proximally along veins between apical cells, distally between the 3A and 2A veins near their junctions with CuA 2, on the join between CuA 2 –CuA 1 veins at the nodal line intersection on vein M 3+4, and apically along vein M between its joins with the M 1+2 and RP veins; outer wing margin clearly present for entire length; basal membrane colourless to pale brown; veins predominantly pale brown. Hind wing: 6 apical cells (very rarely 5 on one wing); no infuscation on or along ambient vein; width of 1st cubital cell at distal end variable, usually less than that of 2nd cubital cell; anal lobe broad with vein 3A curved, separated from wing margin; veins M and RP fused basally; anal cells 2 and 3 with basal grey infuscation, fading out distally; veins pale sandy-brown, tending darker basally.

Legs: Two erect spines on fore femora; fore and mid coxae and trochanters pale brown, broad anterior dark brown fasciae on ventral and anterior faces of coxae, and 2 to 3 smaller dark brown fasciae on anterior trochanter faces; fore and mid femora, tibiae and tarsi pale to medium brown, grading to black on claws; hind coxae pale brown with extensive dark brown on anterior and dorsal faces; hind femora with pale and dark brown longitudinal fasciae; hind tibiae medium brown with 6 tibial spurs, and clusters of very small spines at distal end of tibiae (tibial comb and thumb of tibial comb); tarsi medium brown, grading to black on claws.

Timbal ( Fig. 1C ). Completely covered by a very rigid black timbal cover, not bulbous, tightly fused to tergites 1 and 2, covered with gently curved, near vertical striations produced by micro-ridging of the surface; removal of the cover shows the timbal to contain four long timbal ribs; ribs 3 and 4 fused dorsally to basal spur; ribs 1 and 2 juxtaposed dorsally to (but not fused to) basal spur, these two ribs fused ventrally; three very prominent intercalary ribs; an elongated ridge located on the timbal plate posteriorly to long rib 4 suggesting a possible additional unconnected rib, its morphological status uncertain; a narrow basal dome lies parallel to, and dorsoposteriorly to, long rib 4; anterodorsal area of timbal plate filled by a shallow and well-defined ridge; posterior area of timbal plate contains gentle ridges and a shallow domed structure.

Opercula ( Fig. 1D ). Completely covers timbal cavity, just overlapping tergite 2; broadly ovoid in outline; well developed suture visible, marking the fused junction between the anterior remnant of the epimeron and the main posterior segment of operculum; the area anterior to the suture is black; posterior and lateral to suture the colour ranges between dark brown and pale brown along distal and lateral margins; posterior area immediately adjacent to suture slopes downwards (as viewed ventrally) towards suture; meracantha spike overlaps opercula plate.

Abdomen ( Fig. 1B ). Overall form short and very broad; in cross-section, tergites strongly convex, epipleurites reflexed ventrally from junction with tergites; tergites 2 and 3 wide, together making up nearly half of abdominal length; tergites 1 and 2 black, covered medially by dense, very short silvery pubescence and patches of waxy exudation; tergites 3–7 shiny black, grading to brown on posteroventral margin of tergite 7, with localized wax patches on especially tergite 3; tergite 8 deep brown to black along anterior margin, also as a narrow fascia along dorsal midline, and as a narrow band along posterior dorsal and lateral margins; otherwise sandy-brown. Sternite II dominantly black; sternite III pale brown; sternite IV black medially, grading to brown laterally; sternites V to VII brown, paler towards sternite VII; sternite VIII pale yellow-brown; sternite IX brown medially, sandy brown laterally; sternites all covered by very short silvery pubescence.

Genitalia ( Fig. 1E, F ). Pygofer black to dark brown anterodorsally, remainder pale sandy brown; distal shoulders broad, rounded in lateral view; upper lobes undeveloped; lower lobes clearly developed, distally rounded in lateral view, somewhat irregular in ventral outline; dorsal beak small but clearly developed, part of chitinized pygofer; uncus undivided, with enlarged median lobe which is somewhat finger-like in lateral view, widest between subapical rounded lobes, and apically tending to be bilobed; claspers absent. Aedeagus with basal plate in lateral view sharply angled to nearly 180°; in dorsal view with short apical arms, the base broad and long, deeply furrowed along midline; basal portion of basal plate directed forwards, away from thecal shaft; ventral rib fused with basal plate; junction between theca and basal plate fused and rigid; thecal shaft recurved to as much as 360°; pseudoparameres absent; thecal apex chitinized; no subapical cerci; no flabellum.

Female: ( Fig. 3B ). Head, pronotum and mesonotum mostly very similar in colours and markings to male, in some specimens the colour is predominantly medium to dark brown rather than paler brown; legs as in male, although again noting the darker brown colouration of some specimens; wings with identical structures and markings to male.

Abdomen, tergite 1 narrow, mostly black, tending paler along posterior margin; tergite 2 slightly wider along dorsal midline than tergites 3–7, with extensive short silvery pubescence medially, otherwise shiny black; tergite 3 predominantly shiny black, with pale brown area anteroventrally; tergites 4–7 predominantly shiny black, with brown on ventral reflexed areas; tergite 8 deep brown to black along entire anterior area, with the remainder sandy brown, the boundary between these two colour zones irregular; tergite 9 with wide irregular black dorsal to sub-medial colouration, dorsally forming a broad midline extending full width of tergite, interrupted by a narrow medial longitudinal sandy brown fascia; remainder of tergite 9 sandy brown to brown, with diffuse brown lateral stigma; sternite I dark brown to black; sternites II brown; sternites III to VII dark brown; ovipositor sheath black, in lateral view anteriorly lying subparallel to sloping tergite margin, distally extending 0.7–1.3 mm beyond the apex of the tergite.

Measurements. Table 1 compares measurements from various locations. These data show a close coherence of the morphological dimensions across the specimens representing the widely separated populations sampled.

Distribution, habitat and behaviour ( Fig. 2 ). The previously recorded distribution of this species ( Moulds, 1990, 2012) extends from 40 km west of Kimba at the top of Eyre Peninsula, southeastern South Australia, northeastwards to Hattah Lakes and Wyperfield National Parks, in the far north-west of Victoria. The following are additional locations: QUEENSLAND: 1♂, QMT196193, Pulchera Waterhole, Mulligan River, 7 Nov 2010, W.C.Q., 23°55.863'S 138°38.117'E, A.J. Emmott. In cane grass, on dune, Ethabuka Reserve. Photographed Specimen. 1♀, QMT196194, Pulchera Waterhole, Mulligan River, 7 Nov 2010, W.C.Q., 23°55.863'S 138°38.117'E, A.J. Emmott. In cane grass, on dune, Ethabuka Reserve. Photographed Specimen; 10 ♂, 4♀, Pulchera Waterhole, Mulligan River, as previously. (QM). 1♂, 2 miles W. of Windorah, southwestern Qld., 10.iv.1971, G.B. Monteith (UQIC, QM). 1♂, 1♀, Sand dune crest, c. 5.6 km northwest of Windorah, southwest Qld., on Crotalaria eremaea , A.E., 4.ii.2010, 25°23.47'S 142°36.82'E, male audio recorded; 1♂, sand dune crest, c. 5.7 km northwest of Windorah, southwest Qld., on Grevillea stenobotrya , A.E., 6.ii.2010, 25°23.40'S 142°36.65'E (AE). 1♀, Ourdel Stn., nr. Windorah, southwest Qld. in burrow on dune, 9.iii.2007, S. Wilson; 11♂, 2♀, 09.AU.QL.DUN.01-02, 27 km southeast of Windorah, eastern margin of Cooper Creek floodplain, southwest Qld, 2.ii.2009, 25.4811°S 142.832°E, K. Hill, D. Marshall, male audio recorded. (MSM). NORTHERN TERRITORY: 29♂, 9♀, Finke R. crossing, 120 km SW of Alice Springs, N.T., 20.i.1984, M.S. & B.J. Moulds; 191♂, 82♀, Finke River near Glen Helen Gorge, N.T., 28.i.1984, M.S. & B.J. Moulds; 5♂, Ormiston Gorge, 130 km W. ofAlice Springs, N.T., 29.i.1984, M.S. & B.J. Moulds; 4♂, 1♀, Kings Canyon, George Gill Rg., N.T., 31.i.1984, M.S. & B.J. Moulds; 3♂, 1♀, 29 km NE of Curtin Springs Hstd., E. ofAyers Rock, N.T., 2.ii.1984, M.S. & B.J. Moulds; 3♂, 1♀, 28 km E. of Curtin Springs Hstd., E. of Ayers Rock, N.T., 6.ii.1984, M.S. & B.J. Moulds; 1♂, 10.AU.NT.LSA.02, c. 105 km ESE Yulara, Ayers Rock Resort, Lasseter Hwy, 1.ii.2010, 25.2455°S 131.992°E, K. Hill, D. Marshall, male audio recorded; Aural record: 1♂, 10.AU.NT.LSB., c. 25 km ESE of Yulara, Ayers Rock Resort, Lasseter Hwy, 2.ii.2010, 25.2202°S 131.23°E, K. Hill, D. Marshall; c. 105 km ESE Yulara, Ayers Rock Resort, Lasseter Hwy, 1.ii.2010, 25.2455°S 131.992°E, K. Hill, D. Marshall, male audio recorded (10.AU.NT.LSA.02); 1♂ aural record. (MSM). SOUTH AUSTRALIA: 3♂, NNW of Tingatingana Ck., Strzelecki Creek, S.A., 23.i.1976, in sand dunes, 28°44'S 140°09'E, M.S. & B.J. Moulds; 14♂, near Moomba Gas Field, S.A., 24.i.1976, in sand dunes, approx. 28°05'S 140°13'E, M.S. & B.J. Moulds; 1♂, 12km SSW of Mungerunn (Mungerannie), [Birdsville Track], S.A., 28°7'22"S 138°39'23"E, 4.iii.2003, stoney desert, mu005; 6♂, 15.AU.SA.CCK, Cooper Creek, main channel on Birdsville Track, 30.i.2015, 28°35.707'S 138°42.902'E, D. Marshall; 1♂, 15.AU.SA.CCM, 17 km S of Cooper Ck main channel, Birdsville Track, 30.i.2015, audio recorded, 28°43.534'S 138°37.394'E, D. Marshall; 2♂, 15.AU.SA.CCN, 72 km S of Cooper Ck main channel, Birdsville Track, 30.i.2015, audio recorded, 29°10.731'S 138°24.357'E, D. Marshall; 1♂, Strzelecki Track, c. 8 km ENE of Arkaroola Rd jct, 31.i.2015, audio recorded, 29°31.211'S 139°53.484'E, D. Marshall; 6♂, 3♀, 15.AU. SA.SZA, Strzelecki Track, c. 17 km ENE of Arkaroola Rd jct, 31.i.2015, audio recorded, 29°28.081'S 139°57.133'E, D. Marshall; 1♂ audio recorded, Strzelecki Track, c. 32 km NE ofArkaroola Rd jct, 31.i.2015, 29°20.511'S 140°01.484'E, D. Marshall; 1♂ audio recorded, Strzelecki Track, 31 km S of Strzelecki Crossing, 1.ii.2015, 29°12.900'S 140°04.463'E, D. Marshall. (MSM). 1♂ photographed, Cooper Ck floodplain, Beach Energy Callawonga Camp, approx 87 km WNW of Moomba, 27.1.2015, 27°55.6214'S 129°20.4354' E, Jan Scott. (JS). WESTERN AUSTRALIA: 1♂, East Hyden, W.A., 29.i.1985, S. Lamond; 1♂, 35 km E of Pindar, W.A., 11.ii.2001, M. Powell, D. Knowles; 1♂, 1♀, AU.WA.EEN, 18 km E of Eneabba, 21.i.2003, audio recorded, 29°45.404'S 115°25.939'E, Moulds, Marshall, Vanderpool (MSM).

A species with a preference for the arid regions of Central Australia, including southwest Queensland, southeastern and northeastern South Australia, northwestern Victoria, and semi-arid shrubland regions of southwestern Western Australia. It inhabits dense patches of low to medium height vegetation on sandy soils, very commonly on sand dunes, sometimes on dunes quite isolated from more extensive dune fields, and frequently in general proximity to ephemeral creeks and lakes. Vegetation on which this species has been found includes Crotalaria eremaea (Rattlepod) , Grevillea stenobotrya (Sandhill Spider-flower), and Zygochloa paradoxa (Sandhill Canegrass) . It is a relatively sedentary species, tending to remain for extended periods in the same general location. Following heavy summer rains, records indicate that it emerges in relatively large numbers.

ms, milliseconds; n, number of measurements; RR, repetition rates.

Calling songs

Macrosyllables are coherent sets of multiple syllables, comprising distinct and measureable units. Echemes result from the extended merging or near coalescence of sets of macrosyllables, typically forming a continuous buzzing element.

Figures

Figure 1. Arenopsaltria nubivena, 5.6 km west of Windorah, southwest Queeensland. (A) fore and hind wings; (B) lateral abdomen view; (C) left timbal, posterior margin at right, dorsal edge at top; (D) left opercula; (E, F) male pygofer and genitalia—E, lateral view; F, ventral view. Terminology for the opercula follows de Boer (1999; note that the crest is described fully by that author as “crest around distolateral corner of basal part of operculum”). Terminology for timbals: LR1 to LR4, long ribs 1 to 4; SR, short (intercalary) ribs; TP, timbal plate. Terminology for pygofer: aed, aedeagus; as, anal styles; at, anal tube; bl, basal lobe of pygofer; bp, basal plate; db, dorsal beak; ds, distal shoulder; md, median lobe of uncus; sl, subapical lobe of uncus. Length of pygofer 3.8 mm. Scale bars 1 mm, except wings (5 mm).

Figure 2. New distribution records for Arenopsaltria nubivena. Filled arrows indicate locations of audio recordings. The generalized distribution of A. nubivena in South Australia and northwestern Victoria, shown by the heavy circled line, is from Moulds (1990, 2012), and marks the known distribution prior to this work. The dotted lines are roads. The dashed lines are State boundaries. The dot-dash line shows the approximate boundary of the ecoregion which defines the dominance of deserts and xeric shrublands within inland Australia (National Reserve System map, published by Australian Government). The filled arrows mark the locations of the audio recordings of A. nubivena illustrated in this paper. The hollow arrows show the locations of the audio recordings of A. fullo and A. pygmaea. The general locations of the major dunefields and other relevant areas noted in the text are labelled.

Figure 3. Arenopsaltria nubivena (Walker); (A) male, Queensland Museum reference QMT196193, body length 22.6 mm; (B) female, QMT196194, body length 21.7 mm. Both specimens from Pulchera Waterhole,Mulligan River, Ethabuka Reserve, southwest Queensland.

Figure 4. Arenopsaltria nubivena (Walker), male holotype, body length 21.4 mm, held in the British Museum of Natural History.

Figure 5. Arenopsaltria nubivena, waveform plots of calling songs from 5.6 km west of Windorah, southwest Queensland; (A) general view showing the relatively uniform, continuous buzzing song, but showing two short breaks (marked by hollow arrows); (B) time expanded segment ofcalling song showingthe repeated macrosyllables, each withsix dominantsyllables,the arrows defining thelimits of theindividual macrosyllables;(C) higher resolution waveformplot of two macrosyllables,the filledarrowmarking theboundary between themacrosyllables. The six dominant syllables (DS) each comprise 5 to 7 high amplitude carrier wave pulses. The time intervals between the dominant and secondary syllables (SS) comprise lower amplitude background pulses,variably frequency modulated;the horizontalarrows define the syllable repetition rates (RR) and the intra-syllable durations between the dominant and secondary syllables. Field recordings, filtered to 1 kHz.

Figure 6. Arenopsaltria nubivena, waveform plots of calling songs from 19 km east-southeast of Windorah, southwest Queensland. (A) song segment with three dominant syllables in each macrosyllable, the hollow arrows marking the macrosyllable limits; (B) time expanded segment of three macrosyllables each with six dominant syllables, the limits of each marked by the arrows; (C) end segment of an extended buzzing element showing macrosyllables (limits marked by arrows) with three syllables, but with the third syllable having a strong reduction in amplitude; following the buzz element, separated by 17 ms, is a macrosyllable comprising three syllables, the third syllable also strongly reduced in amplitude. Field recordings, filtered to 4 kHz.

Figure 7.Arenopsaltria nubivena, waveform plots of calling songs from;(A) 105 km east-southeast ofYulara, southern Northern Territory, a higher resolution plot of buzzing element showing the macrosyllables, each with three dominant syllables, the hollow arrows marking the macrosyllable limits. (B, C) from 18 km east of Eneabba, southwestern Western Australia, higher resolution plots;B, showing a transition from initially six syllables per macrosyllable to three syllables per macrosyllable; C, further time expanded plot of three macrosyllables, each with six dominant syllables, the initiation of each macrosyllable marked by a higher amplitude syllable; (D) from 72 km south of Cooper Creek crossing, Birdsville Track, Strzelecki Desert, northeastern South Australia, showing macrosyllables with three and six dominant syllables, the arrows marking the macrosyllable limits.Field recordings, A filtered to 4 kHz, B to 5 kHz, C to 2 kHz,D to 1 kHz.

Figure 8. Arenopsaltria nubivena, higher resolution waveform and accompanying amplitude spectra plots of complete macrosyllables and segments of adjacent macrosyllables. The two recordings are of the calling songs, from 5.6 km west of Windorah, southwest Queensland. The macrosyllables each have six dominant syllables. A and C are waveform plots showing the high amplitude dominant syllables (labelled DS in A), these separated by smaller secondary syllables (labelled SS in A). Between these syllables are mostly low amplitude background pulses, possibly reverberation induced. The results of measurements on the carrier wave pulses are shown above the waveforms, showing the limits and calculated frequency (in kHz) within each of the short song segments, these mostly corresponding to the syllables and background pulses. B andD are the respective amplitude spectra of each of the two waveforms shown inA andC. The numbers adjacent to the selected spectral peaks are kHz. The measured frequency ranges (horizontal lines) and weighted mean frequency (downward pointing arrows), which are derived from the waveform plots, are shown. Song recordings filtered to 1 kHz.

Figure 9. Comparative plots of amplitude spectra of: (A) Arenopsaltria pygmaea from 14 km northeast of Jurien Bay, Western Australia; (B) Arenopsaltria fullo, from Mullaloo Beach, north of Perth, Western Australia; (C–F) Arenopsaltria nubivena, from, respectively; 5.6 km west of Windorah, southwest Queensland; 72 km south of Cooper Creek crossing, Birdsville Track, Strzelecki Desert, South Australia; 105 km east southeast of Yulara, southern Northern Territory; and 18 km east of Eneabba, Western Australia, respectively. Note the weak extensions in all the plots to frequencies higher than the defined dominant frequency. The horizontal bars define the high amplitude frequency envelope of each spectrum, used to estimate the dominant frequency and the nominal bandwidth of each song. Each spectrum shown only between 3 to 16 kHz.