Platypleura minima Lee and Marshall, 2023

Lee, Young June, Marshall, David C., Mohagan, Alma B., Hill, Kathy B. R. & Mohagan, Dave P., 2023, Revised checklist of Cicadidae (Insecta: Hemiptera) of Mindanao, Philippines, with descriptions of a new genus and nine new species, Journal of Natural History 57 (1 - 4), pp. 193-242 : 199-204

2. Platypleura minima Lee and Marshall sp. nov.

( Figures 4 , 5 , 6 (A))

Type material

Holotype. Male, specimen code 12.PH. MN. MUS.06, PHILIPPINES, Mindanao, Bukidnon, Maramag , Mt. Musuan , 7°52.62 ʹ N, 125°4.19 ʹ E, 21 April 2012, K. B. R. Hill, D. C. Marshall and A. B. Mohagan ( NMPM).

Etymology

The specific name is the feminine form of the Latin adjective minimus meaning ̍smallest̾ or ̍least̾, in reference to the black and grey patterns on the wings, which is the lightest or least infuscated among the Philippine species of Platypleura .

Measurements of type (1 male)

Length of body: 18.7. Length of head and thorax together: 9.6. Length of abdomen: 9.1. Width of head including compound eyes: 8.3. Width of pronotum: 10.3. Width of mesonotum: 7.9. Width of abdominal tergite 3: 8.4. Length of fore wing: 25.5. Width of fore wing: 9.2. Wing span: 59.1.

Diagnosis

This new species is very similar to Platypleura bella Lee and A. Mohagan sp. nov. but smaller in body size (outside of the range of all the body part sizes of the available male specimens of P. bella ) and has less infuscation on the fore wing and the hind wing with some distinguishing points: anal cell 2 fuscous on about basal one-fourth (vs fuscous on about basal one-third to two-thirds in P. bella ); anal cell 4 fuscous on about basal one-third (vs fuscous on about basal half to two-thirds in P. bella ); anal cell 5 fuscous on about basal one-third (vs fuscous on about basal half to two-thirds in P. bella ); longitudinal length of light greenish ochraceous portion of tergite 8 long, about four times as long as black portion (vs very short, shorter than one-third as long as black portion in P. bella ); and timbal cover mostly greenish ochraceous (vs mostly black to fuscous in P. bella ).

The calling songs are readily distinguishable from each other, as discussed below.

Description of male

Head. Vertex slightly greenish ochraceous with the following black marks: median large spot enclosing ocelli, with its anterior end reaching anterior margin of vertex; a pair of small longitudinal spots between lateral ocelli and compound eyes; a pair of small spots on posterolateral corners of vertex; a pair of short obliquely longitudinal fasciae between postclypeus and compound eyes; and a pair of narrow fasciae along compound eyes. Distance between lateral ocelli and compound eyes distinctly longer than twice the distance between lateral ocelli. Antenna mostly castaneous but pedicel fuscous. Postclypeus not swollen anteriad; greenish ochraceous with a medial longitudinal black fascia, wider anteriorly, and transverse fasciae along transverse grooves, becoming indistinct going posteriad. Anteclypeus dull brown except ochraceous median ridge. Rostrum slightly greenish ochraceous but darkened towards apex to become black apically; with apex not reaching medial part of posterior margin of abdominal sternite II. Lorum black except ochraceous anterior and lateral margins. Gena black to fuscous with greenish ochraceous spot on posterior margin.

Thorax. Pronotum ochraceous to greenish ochraceous. Inner area of pronotum with the following black to fuscous marks: posteromedial inverted T mark; indistinct spot on anteromedial part of inner area; rather indistinct irregularly shaped marks along paramedian fissures; a pair of irregularly shaped marks along lateral fissures; and a pair of curved fasciae along lateral margins of inner area. Pronotal collar darkened anteriorly and laterally on both sides. Anterolateral pronotal collar broadly developed and roundly angulated with an angle of 100–110°, expanding to a width much greater than the widest width of posterior pronotum, mesonotum and abdomen. Mesonotum reddish ochraceous with the following black marks: median longitudinal fascia, with its posterior end widened and reaching anterior margin of cruciform elevation, but its anterior end not reaching anterior margin of mesonotum; a pair of small transverse spots enclosing scutal depressions; a pair of large semicircular spots on submedian sigilla, with their anterior ends reaching anterior margin of mesonotum; and a pair of long inverted triangular marks on lateral sigilla, with their anterior ends reaching anterior margin of mesonotum. Cruciform elevation greenish ochraceous. Fore-, mid- and hind trochanters and femora brown to dark brown.

Wings. Fore wing outer margin slightly curved outwardly (not straight or linear). Fore wing with venation ochraceous to reddish ochraceous, darker apically; furnished with white patch on about basal two-fifths to one-half (hyaline on remaining part: about apical half) and with the following infuscations: three spots on radial cell; mark on both ends of both ulnar cells 1 and 2; rather indistinct marks on basal half and tiny spot on apical end of ulnar cell 3; indistinct small marks on medial cell; mark on both apical and basal ends of apical cell 1; irregularly shaped small marks on subapical parts of apical cells 2–7, sometimes indistinct; one or two tiny dots on apical ends of apical cells 2–7; and two spots on apical end of apical cell 8. Basal membrane dark grey with light green margin. Hind wing fuscous except outer marginal area and apical portion of apical cells 1–6. Anal cell 2 fuscous on about basal one-fourth. Anal cell 4 fuscous on about basal one-third. Anal cell 5 fuscous on about basal one-third. Hind wing jugum grey with light green margin.

Operculum mostly fuscous except greenish ochraceous margin; semicircular, transversely wide; short, nearly reaching posterior margin of abdominal sternite II. Opercula overlapping medially.

Abdomen obconical in dorsal view, short, slightly shorter than head and thorax together; mostly black with light greenish ochraceous caudal margin on each of tergites 3–7. Tergite 8 mostly light greenish ochraceous except for narrow anterior part, with longitudinal length of light greenish ochraceous portion about four times as long as black portion. Timbal cover mostly greenish ochraceous with black to fuscous patch posteriorly;semicircular, wider than long. Timbal concealed by timbal cover in dorsal and lateral views. Abdominal sternites black with greenish ochraceous to dull brown caudal margin on each of sternites II–VII.

Genitalia. Pygofer long ellipsoidal with acuminate apex (wide dorsal beak) in ventral view. Uncus simple, not bifurcate, with apical margin rounded. Aedeagus not tapering down to apex.

Song ( Figure 5 )

About 103 s of song was recorded from uncollected males at Mt. Musuan, Bukidnon, on 21 April 2012, at 11:05 AM. An additional 95s of song was recorded on 7 July 2010, at the same location, although no specimens were collected. The sound is a continuous frequency-modulated whining buzz, similar in quality to a car alarm. Pulses of approximately uniform amplitude are regularly produced at about 435–455 pulses/s in the 2012 recordings, and at 380 pulses/s in the 2010 recording. The sound sweeps upward and downward (the latter more slowly) in pitch at about 3.7–3.8 cycles/s in all recordings, with amplitude subtly shifting concordantly. Most sound energy lies within the range 6.5–12.5 kHz, with the peak shifting from about 8.5 to about 9.5 kHz across the cycles.

Males sang from the upper surface of lateral branches of an Acacia mangium tree with the head elevated and the abdomen and wings angled downward. This together with their lichenlike colour pattern contributed to making them difficult to locate.

The song of P. minima differs from that of P. bella in the much slower rate of concordant amplitude and frequency oscillation,ca.3.7–3.8 cycles/s (vs 35–40 cycles/s in P. bella ). This rate difference, nearly an order of magnitude, is not likely to be caused by environmental temperature differences during recording because the underlying pulse rate is similar for both species. Furthermore, some platypleurine species have been shown to thermoregulate (e.g. Sanborn et al. 2004), which reduces the significance of environmental temperature.

Remarks

Endo and Hayashi (1979) reported Platypleura sp. aff. nobilis (Germar, 1830) (TL: Java) based on a male specimen collected from Mt. Apo. Lee (2010) identified the specimen as P. elizabethae . However, this record is more likely to be Platypleura minima because the cloudy patterns on the wings of Platypleura nobilis are more similar to those of P. minima than to P. bella , P. elizabethae or P. transitiva , which was misidentified as P. elizabethae by Lee (2010, 2015).

The dorsal habiti of male specimens of several Philippine Platypleura species are shown in Figure 6 for comparison.

Figures

Figure 4. Platypleura minima Lee and Marshall sp. nov., holotype, male, Mindanao, Philippines. (A) Dorsal habitus; (B) ventral habitus; (C) pygofer, oblique ventral view.

Figure 5. Platypleura minima Lee and Marshall sp. nov. Waveforms (A, C) and spectrograms (B, D) of male calling song at two time scales.

Figure 6. Male dorsal habitus of the Platypleura species from the Philippines. (A) Platypleura minima Lee and Marshall sp. nov.; (B) Platypleura bella Lee and A. Mohagan sp. nov.; (C) Platypleura elizabethae Lee, 2009; (D) Platypleura transitiva Lee, 2021; (E) Platypleura dinagatensis Lee, 2016.