Clinopsalta semilunata, Popple & Emery, 2017

Popple, Lindsay W. & Emery, David L., 2017, Two New Species of Clinopsalta Moulds (Hemiptera: Cicadidae) and Additional Distribution Records for Clinopsalta adelaida (Ashton), with Notes on their Distinctive Calling Songs, Records of the Australian Museum 69 (4), pp. 237-256 : 243-253

Clinopsalta semilunata sp. nov.

Figs 2B ; 4–6

Notopsalta sp. F : Ewart (1998).

Holotype: ♂, AUSTRALIA QLD, Old Thanes Creek Road , Pratten, 1.xi.2015, Recorded, L. W. Popple, 28.0912°S 151.7360°E, 211-0008, QM reg. no. T237103 ( QM) . Paratypes: 1♀ AUSTRALIA Queensland, 6 km west of Thane , 11.xii.2001, hand-collected, L. W. Popple 28°09'41"S 151°57'59"E, 211-0006, QM reg. no. T237104 ( QM) ; 1♂, Jct. Engineer-Auburn Rds., Chinchilla , S. Qld., 10 Oct 1997. Recorded ; 1♂, Wongongera Ck., Miles, S. Qld. 26°30.68'S 150°29.30'E, 3 Oct 1997 ; 1♂, “Red Ridge”, Miles, S. Qld. 26°47.34'S 150°23.85'E, 2 Oct. 1997 (all AE) ; 2♂♂, 70 km E. Roma, Qld , 26°37.1'S 149°29.40'E, 19.x.2011, N. C. and D. Emery (both DE) ; 4♂♂ 1♀, AUSTRALIA Queensland, 6 km west of Thane , 11.xii.2001, hand-collected, L. W. Popple 28°09'41"S 151°57'59"E, 211-0001, 211-0003 to 211-0005, 211-0007 (♀) ; 1♂, same data as holotype (all LWP) ; 1♂, AUSTRALIA Queensland, 6 km west of Thane , 11.xii.2001, hand-collected, L. W. Popple 28°09'41"S 151°57'59"E, 211-0002 ( MSM) .

Additional location with audio recordings: Swains Road , Binjour Plateau , Qld , 25°32'00"S 151°29'59"E; Redvale Rd west of Binjour , Qld , 25°31'56"S 151°25'32"E; Yelarbon State Forest, Qld, 28°32'17"S 151°06'22"E (all LWP) .

Description. Male ( Figs 2B ; 5A,B ; 6 ). Head. Supra-antennal plate and vertex olive-brown anteriorly, black posteriorly; frons brown with contrasting areas of black colouration posteriorly on each side of medial line; mandibular plates and genae mainly olive-brown and covered by silver–yellow pubescence; small median brown triangular fascia, extending and widening posteriorly from near median ocellus to pronotal margin along the epicranial suture; ocelli pink; compound eyes brown. Postclypeus predominantly black, olive-brown along margins and between the transverse ridges; anterior median area coloured brown or reddish-brown; anteclypeus mainly black; rostrum dark brown; antennae dark brown.

Thorax. Pronotum mainly medium brown, with a lighter brown to olive-brown medial fascia, bordered with black colouration that widens anteriorly of pronotal collar and also towards proximal margin; dorsal and lateral fissures narrowly and diffusely black; pronotal collar olive-brown, with lateral margins ampliate and often darker at extreme lateral margin. Mesonotum with submedial sigilla black, fused anteriorly, with rounded posterior terminations; lateral sigilla black, sharply defined, elongated and narrowing posteriorly area posterior of submedian sigilla with yellow to yellow-brown highlights; remainder of mesonotum, including lateral edges adjacent to lateral sigilla, area surrounding scutal depressions and length of parapsidal suture between submedian and lateral sigilla, olive-brown to brown; scutal depressions black; cruciform elevation dark brown to black; with inconspicuous and sparse silvery-yellow pubescence, more apparent adjacent to wing grooves. Metanotum brown; black medially.

Wings. Fore wing costal vein translucent, olive-brown from base to node, dark brown along remainder; other venation olive-brown to brown, dark-brown distally; basal membrane orange. Hind wing venation brown to light brown, with light brown opaque plaga around margins of anal cell 3, adjacent to vein 3A and vein 2A; six apical cells.

Legs. Coxae and trochanters pale brown to olive brown; meracanthus spikes pale brown to olive-brown, slightly overlapping opercula; fore, mid and hind femora pale brown with weak brown longitudinal fascia developed on posterior, dorsal and anterior faces; fore, mid and hind tibiae pale brown; tarsi mainly pale brown; claws brown, darker apically; spines of fore femora dark brown.

Opercula ( Fig. 5B ). Broadly rounded; predominantly brown; plates undulating with medial areas slightly depressed.

Timbals ( Fig. 2B ). Five long ribs; ribs 4–5 both unattached to adjacent ribs and shorter than ribs 1–3; ribs 1–3 fused dorsally, but not ventrally.

Abdomen. Tergite 1 dark brown to black; tergites 2–7 mainly reddish-brown, often dark brown to black on anterior margins, ochraceous on posterior margins, with a weak discontinuous line of dark colouration extending along anterior dorsal and lateral margins; silvery pubescence most prominent along lateral edges of anterior tergites. Sternites olive-brown, often faded to yellow-brown, sometimes paler medially; intersegmental membranes yellow-brown.

Genitalia ( Fig. 6 ). Pygofer with black colouration dorsally, extending to beak and along posterior lateral edges to upper lobe; ochraceous over the remainder, anal styles light orange; claspers conspicuously elongated, extending posteriorly beyond termination of pygofer, bluntly rounded apically; uncus vertically narrow, relatively short, with rounded termination; Aedeagus trifid, pseudoparameres clearly longer than endotheca; endotheca soft, fleshy.

Female. ( Fig. 5C ). Similar to male in general colouring and patterning, although often with more extensive areas of paler colouration.

Head. Mainly olive-brown. Supra-antennal plate and vertex pale olive-brown anteriorly, dark brown to black posteriorly; frons olive-brown with contrasting areas of black colouration posteriorly on each side of medial line; mandibular plates and genae pale olive-brown; ocelli pink; compound eyes brown. Postclypeus predominantly olive-brown, tending orange-brown medially, with brown to dark brown longitudinal areas on either side of midline; anteclypeus, rostrum and antennae dark brown.

Thorax. Pronotum as in male, although often with a broader medial fascia. Mesonotum with submedial sigilla brown, separated anteriorly, with slightly darker and rounded posterior terminations, sometimes longer than in male; lateral sigilla dark brown, elongated and narrowing posteriorly, diffuse along margins; area posterior of submedian sigilla with yellow to yellow-brown highlights, as in male; remainder of pronotum, including lateral edges adjacent to lateral sigilla and area surrounding scutal depressions, olive-brown to brown; scutal depressions brown; cruciform elevation dark brown; with inconspicuous and sparse silveryyellow pubescence, more apparent adjacent to wing grooves. Metanotum dark brown.

Legs. Appearance as in male.

Abdomen. Tergite 1 pale brown; tergites 2–8 mainly reddish brown, with dark lines of black colouration along median dorsal margins; abdominal segment 9 brown to pale brown, with a pair of narrow, diffuse, dark brown dorsolateral fasciae, extending from the anterior margin and not reaching the posterior margin. Sternites pale brown to olive-brown; intersegmental membranes orange-brown. Ovipositor sheath barely extending beyond the posterior termination abdominal segment 9.

Measurements (in mm; range with mean in parentheses: 12 males, 2 females). Body length: male 16.1–19.3 (17.9); female (incl. ovipositor) 18.4–18.9 (18.7). Fore wing length: male 19.0–23.5 (22.1); female 22.9–23.9 (23.4). Forewing length/width ratio: male 2.57–2.86 (2.71); female 2.86–2.90 (2.87). Head width: male 5.1–6.3 (5.8); female 5.6–5.9 (5.8). Pronotum width: male 5.0–6.0 (5.6); female 5.5–6.0 (5.8). Abdomen width: male 4.9–4.9 (5.5); female 5.0–5.3 (5.2).

Distinguishing features. Clinopsalta semilunata sp. nov. can be distinguished from C. adelaida and C. autumna sp. nov. by having entirely pale brown to pale green sternites without black markings centrally. In most cases, this feature, and a complete lack of fore wing infuscations, distinguishes C. semilunata sp. nov. from the C. tigris species complex. However, on rare occasions, specimens in the C. tigris species complex may also lack wing infuscations and dark central markings on the sternites. In this situation, C. semilunata sp. nov. can still by distinguished by having a predominantly dark brown rostrum (c.f. mainly brown or olive in paler specimens of C. tigris ).

Distribution, habitat and behaviour. Clinopsalta semilunata sp. nov. is restricted to south-east Queensland where it is known from east of Yuleba east to Binjour Plateau and south to near Thane and Yelarbon State Forest ( Fig. 4 ). Populations appear to occur in association with wattles ( Acacia spp. ), which grow in the middle storey of dry open forest. At the type locality near Thane, C. semilunata sp. nov. appears to occur principally in association with Acacia caroleae . Near Yuleba and in the Gurulmundi area north of Miles, it has been found mainly on Acacia semilunata . Adults have been observed between September and December.

Etymology. The name is derived from Latin lunatus, meaning “moon”, with the prefix semi-, meaning “half”. This refers to the bright markings on the mesonotum, which can appear as two “half-moons”. Additionally, the plant Acacia semilunata is one of the species with which this cicada is commonly associated in inland southern Queensland.

Additional distribution records for Clinopsalta adelaida (Ashton) ( Figs 4 , 7 ). 1♂, Wyalong rest area, NSW, 33°55.33'S 147°14.58'E, 22.xi.2010, L. Popple and D. Emery ; 1♂ (visual and aural observation only, no specimen), 9.8 km W. of Paskeville , SA, 34.02631°S 137.80837°E, 3.xi.2016, L. Popple and A. McKinnon (both LWP) ; 1♂, Pilliga State Forest , 70 km N. of Coonabarabran, NSW, 30°40.52'S 149°32.50'E, 2.xi.2012, N. and D. Emery ; 1♂ 1♀, Whitegum Lookout , Warrumbungle NPk, NSW, 31°18.14'S 149°02.05'E, 680 m, 18.x.2014, N., C. and D. Emery ; 1♂, same location, 5.x.2015, N., C. and D. Emery (all DE) ; 2♂♂, Gravesend , NSW, 21.xi.1998, M. Coombs ; 2♂♂, Gravesend , NSW, 21.xi.1998, M. Coombs ; 1♂ 1♀, same data as previous, 22.xi.1998 ; 1♂, 7 km W. of Gravesend , NSW, 21.xi.1998, M. Coombs ; 2♂♂, same data as previous, 22.xi.1998 (all MC) .

Calling songs

The calling songs of Clinopsalta adelaida , C. autumna sp. nov. and C. semilunata sp. nov. have clear structural similarities. Each of these species produces a complex day song and a dusk song, although the dusk song of C. adelaida has not yet been recorded. The calls broadly consist of regular macrosyllables or echemes, which may or may not be separated by one or more syllables.

The calling song description for C. adelaida is based upon a single recording from Telowie Gorge in South Australia ( Fig. 8 ) and two recordings from Wyalong in New South Wales ( Fig. 9 ). The day calling song of this species is the most complex of all described here and has a characteristic sequence. It begins with closely-spaced sets comprising a macrosyllable (0.019 –0.023 s duration) followed by three higher amplitude syllables (each 0.007 –0.010 s duration), separated by gaps of 0.009 –0.015 s duration. This is followed by a sequence of 10–35 syllable doublets (each 0.016 –0.019 s duration, punctuated by gaps of 0.015 –0.020 s duration). The doublets continue, but are then periodically interrupted by a discrete, higher amplitude macrosyllable (0.040 –0.069 s duration) and doublet (or triplet, 0.014 –0.022 s duration). This quickly progresses into a stable phrase pattern, with each phrase comprising a high amplitude macrosyllable and doublet followed by a series of three or four lower amplitude doublets. The lower amplitude notes are sometimes augmented with an equivalent number (or fewer) sharp wing-snaps (too subtle in available recordings to allow illustration). These wing snaps may continue for a short time in the gaps between the high amplitude notes even after production of the low amplitude notes has ceased. A short time later, the wing snaps also cease and only the high amplitude notes (macrosyllable and doublet) remain, with each phrase ending in a long gap of 0.074 –0.136 s. The phrases then become simplified even further in the final section of the song when the doublets are also dropped, leaving only the macrosyllables, which are then punctuated by even longer gaps of approximately 0.140 s. This final section is typically the longest part of the song (up to 25 s or longer) and it is during this section that the females are expected to respond with a wing-flick (during the gaps), as indicated by the responsiveness of males to simulated wing-flicks ( LWP, pers. obs.) .

The day calling song of C. autumna sp. nov. is similar to C. adelaida ; however its structure is more simplistic and not so strongly transitional. Illustrations of this song are provided in Figs 10–12 . The song commences a burst of strident phrases, which are composed of a macrosyllable (0.027 – 0.055 s duration, 3–6 syllables) followed by two or three single syllables (0.006 – 0.012 s duration), each separated by gaps of 0.018 – 0.074 s duration (all statistics, n = 16 individual recordings). These may be interrupted by segments in which the syllables (or sometimes all but one of the syllables) in each phrase are replaced by two prominent wing-snaps (e.g. Fig. 11D ). In some instances, the song may progress into a sequence whereby the phrases simplify into a single macrosyllable (0.029 – 0.056 s duration), a brief silence (0.035 – 0.071 s), a single syllable, double syllable, or shorter macrosyllable (0.009 – 0.034 s) and a longer silence (0.104 – 0.148 s). In the final section, the song winds down to a long series of macrosyllables (each 3–6 syllables, 0.031 – 0.056 s total duration), each separated by long gaps (0.153 – 0.268 s duration). From the observations of human observers attracting male cicadas using simulated wing-flicks, it is inferred that the female cicada responds with a single wing-flick during the long gap following each macrosyllable in the final section.

The day calling song of C. semilunata sp. nov. is the simplest among the species documented here (see Fig. 13 ). It typically commences with a brief introduction, which is composed of a short echeme (0.071 – 0.133 s duration), a gap (0.045 –0.194), a short sequence of syllables or occasionally syllable doublets (each 0.006 – 0.015 s duration, punctuated by gaps of 0.041 – 0.084 s, total duration 0.691 – 1.283 s), followed by a long gap (0.108 – 0.377 s duration; all statistics, n = 17 recordings). The brief introduction is succeeded by a long series of echemes (each 0.091 – 0.158 s duration), each separated by a long gap of 0.255 – 0.373 s duration. As noted for C. adelaida and C. autumna sp. nov., observations of simulated attraction of male cicadas indicate that the female cicada responds with a single wing-flick during the long gaps.

Based on examination of a single recording for C. autumna sp. nov. and two recordings of C. semilunata sp. nov., the dusk calling songs of these species are both equally simple and monotonous ( Fig. 14 ). In each species, repeated phrases consist of a single discrete syllable followed by a macrosyllable (containing 4–5 syllables). In C. autumna sp. nov., the gaps between each syllable and macrosyllable (and the following syllable) are all of similar duration (0.051 – 0.082 s duration), whereas in C. semilunata sp. nov. the gap following the syllable (0.055 – 0.064 s duration) is considerably shorter than the gap that follows the macrosyllable (0.123 – 0.240 s duration). It is considered likely that C. adelaida also produces a dusk call even though this has not yet been observed or recorded. The function of the dusk calling songs remains unclear, although the repetitive broadcasting of notes could effectively be interpreted as a simplified version of the day calling song. Therefore, it is likely to plays some role in attracting females from the surrounding habitat.

The three species exhibit similar highest amplitude frequency plateaus in their calling songs ( Fig. 15 ). Based on the available recordings, C. adelaida has a plateau spanning from 8.8–11.7 kHz (dominant frequency between 10.4 and 11.6 kHz), C. autumna sp. nov. has a slightly higher plateau ranging from 9.0–13.6 kHz (dominant frequency between 9.8 and 12.1 kHz) and C. semilunata sp. nov. has a plateau of 8.3–12.3 (dominant frequency between 8.9 and 12.2 kHz). None of these species exhibits frequency modulations between the day and dusk calling songs or within the different sections of the more complicated day calling songs.

ACKNOWLEDGMENTS. The authors acknowledge the contributions of Timothy, Nathan and Samantha Emery over more than 15 years of field collections. Thanks are also due to Tony Ewart, Marc Coombs, Max Moulds, Bryce Smith, Rob MacSloy and Kathy Hill for sharing their records and/or observations. In addition, Tony Ewart and Max Moulds provided helpful comments on the draft manuscript. Geoff Thompson (Queensland Museum) provided the high resolution photographs and Hannah Matthews completed the line drawings.

Figures

Figure 2. Photos of male left timbals, with dorsal edge at top and posterior margin at right: (A) Clinopsalta autumna sp. nov., Narellan (31°18.14’S 149°02.05’E); (B) Clinopsalta semilunata sp. nov., Roma (26°33’S 148°47’E).

Figure 4. Map of central and eastern mainland Australia showing the geographical distribution ofClinopsalta adelaida

Figure 5. Clinopsalta semilunata sp. nov.(A) male holotype, Pratten (28.0912°S 151.7360°E) dorsal habitus; (B) male, ventral habitus; (C) female paratype, 6 km W of Thane (28°09’41”S 151°57’59”E) dorsal habitus.

Figure 6.Clinopsalta semilunata sp. nov.: illustration of male pygofer and internal genitalia;(a) viewed laterally from the left;(b) viewed ventrally; (c) aedeagus, viewed laterally from left; and (d) apex of theca, viewed dorsally. Characters include: bpl, basal lobe of pygofer; cl, clasper; db, dorsal beak; ps, pseudoparameres; th, theca; un, uncus; upl, upper lobe of pygofer; vs, ventral support. Specimen from 6 km W of Thane (28°09’41”S 151°57’59”E).

Figure 7. Clinopsalta adelaida (A) male, Warrumbungle NPk, NSW (31°18.14’S 149°02.05’E) dorsal habitus; (B) male, ventral habitus; (C) female, Warrumbungle NPk, NSW (31°18.14’S 149°02.05’E), dorsal habitus.

Figure 8. Male calling song structure of Clinopsalta adelaida, illustrated in wave plot form. (A) a single, complete bout of calling. (B) expanded diagramof the commencing section (fromA above), showing several repeated sets of song notes,each comprising a macrosyllable separated by three syllables, with a magnified example of two sets shown in the excerpt to the right. (C) expanded diagram of the middle of thesong (from A), showingseveral macrosyllables, each separated by asequence of syllables, gradually reducing to one syllable;an expanded version showing two macrosyllables, each followed by a syllable sequence is shown to the right of the figure. Wing snaps are detectible in the latter half of this section; however these proved too subtle for illustration. D: expanded diagram of the latter half of the song (from A), showing repeated macrosyllables, these again expanded for convenience of examination to the right of the main figure. The recording was obtained in the field from Telowie Gorge, South Australia (33°01’S 138°06’E) by LWP using RS2 (see Methods and terminology).

Figure 9. Male calling song structure of Clinopsalta adelaida, illustrated in wave plot form. (A) a single, complete bout of calling. (B) expanded diagram of the commencing section (fromA above), showing several repeated sets of song notes, each comprising a macrosyllable separated by three syllables, with a magnified example of two sets shown in the excerpt to the right. (C) expanded diagram of the middle of the song (from A), showing several macrosyllables, each separated by a sequence of syllables, gradually reducing to one syllable; an expanded version showing two macrosyllables, each followed by a syllable sequence is shown to the right of the figure. Wing snaps are detectible in the latter half of this section; however these proved too subtle for illustration. (D) expanded diagram of the latter half of the song (from A), showing repeated macrosyllables, these again expanded for convenience of examination to the right of the main figure.The recording was obtained in the field from Wyalong, NewSouth Wales (33°55’S 147°14’E) by LWPusing RS4 (see Methods and terminology).

Figure 10. Male calling song structure of Clinopsalta autumna sp. nov., illustrated in wave plot form. (A) a single, complete bout of calling.(B) expanded diagram of the introductory section (from A above), showing several repeated sets of song notes, each comprising a macrosyllable separated by three syllables. (C) expanded diagram of the middle of the song (from A), showing several macrosyllables, each separated by 1–2 syllables. (D) expanded diagram of the latter half of the song (from A), showing repeated macrosyllables. The recording was obtained in the field from Berry, NSW (34°46’S 150°44’E) by LWP using RS1 (see Methods and terminology).

Figure 11. Wave plots illustrating the structure of the complex, introductory part of the male calling song of Clinopsalta autumna sp. nov. from (A) Bargo, New South Wales (34°17’S 150°35’E), (B) Spicer’s Gap, Queensland (28°05’S 152°25’E), (C and D) Rosewood, Queensland (27°37’S 152°37’E), and (E) Berry, New South Wales (34°46’S 150°44’E). D provides an example of where timbal-derived syllables (as shown in C) have been replaced with timed wing-snaps.All recordings were obtained in the field by LWP using RS1 (A and E), RS4 (B), or RS2 (C and D) (see Methods and terminology).

Figure 12. Wave plots illustrating the structure of the simple part of the male calling song of Clinopsalta autumna sp. nov. from (A) Berry, New South Wales (34°46’S 150°44’E), (B) Spicers Gap, Queensland (28°05’S 152°25’E), (C) Rosewood, Queensland (27°37’S 152°37’E), and (D) Bauple, Queensland (25°48’S 152°35’E).All recordings were obtained in the field by LWP RS1 (A), RS5 (B) or RS2 (C and D) (see Methods and terminology).

Figure 13. Wave plots illustrating the male calling song of Clinopsalta semilunata sp. nov. Each plot shows a separate recording, with a brief introductory echeme and syllable sequence, followed by a series of repeated echemes. Recordings are from (A) Pratten (28°05’S 151°44’E), (B) Yelarbon State Forest (28°32’S 151°06’E), (C) Binjour Plateau (25°32’S 151°30’E), and (D) Chinchilla (26°39’S 150°35’E), all in Queensland. All recordings were obtained in the field by LWP using RS2 (A), RS3 (B) or RS1 (C); or by A. Ewart using RS5 (D) (see Methods and terminology).

Figure 14.Wave plotsillustrating the repeated phrase structure ofthe male dusk callingsong ofClinopsalta cicadas,including(A) C.autumna sp. nov. from Cunningham’s Gap, Queensland (28°03’S 152°22’E), and (B) C. semilunata sp. nov. from Yelarbon State Forest, Queensland (28°32’S 151°06’E). Both recording were obtained in the field by LWP using RS1 (A), or RS2 (B) (see Methods and Terminology).

Figure 15. Frequency spectra comparisons between Clinopsalta cicadas, including (A) C. adelaida (from Wyalong, NSW 33°55’S 147°14’E), (B) C. autumna sp. nov. (from Bargo, New South Wales: 34°17’S 150°35’E), (C) C. autumna sp. nov. (from Redwood Park, Queensland:27°34’S 152°00’E) and (D) C. semilunatasp. nov. (from Pratten, Queensland:28°05’S 151°44’E).The horizontal bars show the ranges of each highest amplitude frequency plateau (bounded by the 90th percentile of each amplitude spectrum). Recordings were obtained using RS4 (A), RS1 (B and C) or RS2 (D) (see Methods and terminology).