Pomponia pseudolinearis, Sadasivan, 2021

Sadasivan, Kalesh, 2021, A new species of Pomponia Stål, 1866 (Hemiptera: Cicadidae) from the Western Ghats, with notes on the status of P. linearis (Walker, 1850) from southern India, Zootaxa 5040 (3), pp. 388-403 : 392-401

Pomponia pseudolinearis sp. nov.

( Figs. 3–6 , 7A )

Etymology. The species name ‘pseudolinearis’ alludes to the close similarity to P. linearis ( Walker, 1850) , with which this species was confused in the past.

Material examined. Holotype. Male, Swargamedu, Rajakumari, Idukki District , Kerala State, India. Col. Kalesh Sadasivan, 24.vi. 2019, 800m a.s.l., from an private cardamom estate, male located by its call. Dry pinned specimen . Holotype number THRG 0033 . Deposited in the insect collection facility of University of Agricultural Sciences ( UAS), Bangalore with accession number UASBHT02119124 .

Paratypes (6 males and 4 females). THRG 0030 female , THRG 0031 male , THRG 0032 female, and THRG 0034 male, all bearing the same collection data as the holotype. Of these one male and one female each will be deposited in Research Collection Facility at the National Center for Biological Sciences ( NCBS), Bangalore, and Zoological Survey of India ( ZSI), Calicut. Other paratypes THRG 0015 (male; dry pinned; Ponmudi Hills, Trivandrum Kerala; Col. Kalesh Sadasivan; 01.vi.2019; 910m a.s.l.) , THRG 0016 (male; dry pinned; Rajakumari, Idukki District , Kerala; Col. Kalesh Sadasivan; 24.vi.2019; 850m a.s.l.) , THRG 0017 (male; dry pinned; Rajakumari, Idukki District , Kerala; Col. Kalesh Sadasivan; 24.vi.2019; 800m a.s.l.) , THRG 0036 (male; wet specimen in ethanol; Rajakumari, Idukki District , Kerala; Col. Kalesh Sadasivan; 24.vi.2019; 900m a.s.l.) , THRG 0037 (female; wet specimen in ethanol; Ponmudi Hills, Trivandrum Kerala; Col. Kalesh Sadasivan; 30.vi.2019; 910m a.s.l.) , and THRG 0038 (female; wet specimen in ethanol; Bonaccord Hills, Trivandrum Kerala; Col. Kalesh Sadasivan; 24.vi.2019; 620m a.s.l.) will be retained as voucher specimens in TNHS collections.

Measurements (mm). Holotype. Male. FWL—49.00; FWW—15.00; HWL —25.00; HL—3.00; HW—10; EL—3.00; PL—5.00; PW—14.00; ML—9.00; MW—11.00; AL—22.00; AW—13.50; OPL—7.5; RL—13.00; ABL—17; TL—39.00; CI—333.33; OI—30; PI—280; MI—122.22; OPI—44.12; API—77.27; RI—76.47; FAR— 326.67; FI—288.24; IWR—196; GI—61.36.

Paratypes. Males (n=6): FWL—48±2.45; FWW—15.80±0.84; HWL—22.90±1.95; HL—3.60±0.42; HW—10.80±0.45; EL—2.98±0.05; PL—4.8±0.45; PW—12.68±1.34; ML—9.20±0.84; MW—11.40±0.55; AL—23.20±1.30; AW—14.50±0.84; OPL— 8.00±0.94; RL—11.2±1.64; ABL—17.60±1.39; TL—40.8±2.14; CI—303.33±38.88; OI—27.62±0.77; PI—263±21.10; MI—124.61±10.98; OPI—45.39±3.20; API— 75.98±6.47; RI— 63.89±9.95; FAR—304.08±14.34; FI—273.57±16.92; IWR—211.02±23.35; GI—62.49±0.17.

Females (n=4): FWL—49.40±0.55; FWW—15.40±0.55; HWL—25.40±0.55; HL—3.20±0.27; HW— 10.20±0.45; EL—2.25±0.25; PL—4.90±0.22; PW—15.80±2.17; ML—9.00±0.71; MW—11.60±0.55; AL— 15.60±1.39; AW—13.90±1.30; OPL—4.7±0.45; RL—13.00±0.71; ABL—17.10±0.96; TL—32.7±1.04; CI— 320.00±20.87; OI—22.05±2.11; PI—324±55.50; MI—129.50±11.05; OPI—27.52±2.82; API—110.52±13.57; RI— 76.38±8.16; FAR—321.08±11.25; FI—289.52±14.30; IWR—194.52±2.02; GI—89.071±0.56.

Description of the Holotype (male, THRG 0033) ( Fig. 3A , 4A , 5 , 6 ). The description of the holotype is given in the live state, on preservation in alcohol, the yellows and greens lose saturation and become yellowish-brown, while blacks and greys become dark brown.

Head. In dorsal view, head small, postclypeus anterior margin rounded and prominent; head much wider than long (CI—333.33); general colour of head is green, marked in dark green and black; ocelli pink; the ocular tubercles dark greenish-black; distance between the lateral ocelli and medial margin of eyes twice the distance between the two lateral ocelli; cephalic spots black, epicranial suture and its anterior arms black; vertex on each side bears a triangular greenish patch bordered medially with dark greenish-black; eyes dark brown; scape black, pedicel blackish, and the flagella brown; frons black; supra-antennal plate dark greenish-black; frontoclypeal suture bordered with black; dorsum of postclypeus dark green with transverse dark greenish-black lines in the transverse grooves ( Fig. 5 A&D ). On anterior view, eyes prominent and inferior third of the eyes brownish-black; postclypeus squarish, swollen and its inferior aspect triangular and tapering towards the anteclypeus; postclypeus with a broad pale greenish-yellow transverse band occupying its middle third, superior third greenish-black and inferior third almost black; the transverse pale greenish-yellow band extends to the genae on either side; rest of the groove below the supra-antennal plate black, and this black band expands towards the anterior eye margin; lorum black and covered in greyish pollinosity; anteclypeus basal half green, distal aspect orange-brown and sides black with the greyish pruinescence or pollinosity; labrum pale brownish; mentum tipped with brown; labium pale brown with median groove dark brown, its distal one-fourth black; rostrum reaches abdominal sternite I, at the level where medial margins of the opercula meet ( Fig. 5B ). In lateral view, the posteroinferior border of eyes yellow; postclypeal pale band extending into prothorax ( Fig. 5 A&E ).

Pronotum. Pronotal width almost thrice its length (PI—280); lateral margin of pronotum dentate; lateral angle of pronotal collar broad and rounded and its postero-lateral margin well-developed; rest of the collar thinner; anterior border of the pronotum with the head bears a thin dark green band, which joins the median hourglass-shaped mark; paramedian and lateral fissure prominent; general colour of the pronotum dark green; the edges of the fissures are smeared in brown; ambient fissure marked in thin black; pronotal collar green, region of lateral spine greenishblack, a squarish patch of black near the lateral angle and a small black spot above it on the collar where it meets the pronotum, and a small median line of black on the dorsum as a continuation of the hourglass mark; posterior margin of the collar thinly lined in black ( Fig. 5 A&D ).

Mesonotum. In dorsal view, mesonotum marginally wider than long (MI—122.22); submedian sigillum (ssig), with regular borders, reaching almost half length of mesonotum, black, and bordered with brown medially and yellowish-brown laterally; the lateral sigillum (lsig) black, with irregular borders, more so medially where the yellowish-green of the mesonotal colour encroaches into it, its lateral border bordered with dark green, and the distal end reaches the anterior arm of the cruciform elevation; distal ends of the ssig and lsig on each side connected by an ill-defined brown suffused spot; scutal depression black and this colour encroaches into the anterior arms of the cruciform elevation and posteromedial to it there is an orange triangular patch; cruciform elevation light green and lateral depressions brownish-green, rest of it green. In ventral view, green with pollinosity mostly in the mid-ventral aspect ( Fig. 5 A&D ).

Operculum. Broad, short (OPI—44.12), lateral margin almost straight, angle curved, and medial margin oblique; operculum meets the opposite one at the level of the sternite I and distally it reaches posterior margin of sternite II. Colour light green, with pollinosity on its medial and posterior margins ( Fig. 5C ).

Wings. Wings hyaline, FW long and apex sharp; transparent with infuscations as follows—basal veins of apical segments except space of apical cell 6 including mediocubital crossvein (m-cu); at nodal line intersection and intersections of CuA 2; distal ends of all veins RA 2, RP, M 1 –M 4 and CuA 1; pterostigma and wing margins faintly infuscated; HW with 6 apical cells; 9 minor transparent veinlets/folds in the anal lobe space between veins 3A and 2A on magnification. Veins of FW bright green and nearing the joints black; anterior wing margin till the node green, thinly bordered with yellow, later part brown; those of the HW brown ( Figs. 3A , 4A , 5C ).

Legs. Forelegs with coxae dark green with black suffusion on lateral aspect; femur pale brown with greenishblack marginal bands and medial lower third black; femur with three spines; a primary spine on the proximal aspect of femur (long, sharp-tipped, oblique and, decumbent to the surface of femur); a secondary spine (long, sharp-tipped, erect); and small tertiary spine (sharp-tipped erect spine slightly larger than the primary spine) present distal to the secondary spine ( Fig. 4E ); tibiofemoral joint yellowish; tibia dark greenish-black; meso- and metatarsi yellowish; pretarsus dark greenish-brown; pretarsal claws with base yellow and tip black; middle legs with the same colour scheme as the forelegs; hindlegs with coxae paler green; femur greenish-yellow; tibia and rest of the legs yellow; tibiotarsal joint brown; tibial spines and combs brown; pretarsal claws black at the tip ( Fig. 5 C&E ). Meracanthus (mc) is flat, triangular in shape with short base; lateral border thick; ventral surface concave; passing slightly distal to the distal border of the hind coxa.

Abdomen. Longer than head and thorax together (API—77.27); widest at anterior tergite 3; sides uniformly tapering distally from tergite 3, and tergite 7 & 8 are truncated; colour shiny pale amber brown to orange-brown and margins of segments are dark brown. Timbal covers incomplete laterally, pale brown; medial margin uniformly curved, apex curved and directed towards wing base and its lateral margin gently curved obliquely. In ventral view, sternite colour is pale coppery with the last two segments orange-brown. No tubercles on sternites ( Fig. 5 C–E ).

Genitalia. In ventro-posterior view, distal shoulder of pygofer acute, with apex sharp and directed straight posteriorly, its inferior margin near the tip straight, becoming a smooth curve inferiorly towards the basal lobes, the pygofer bears sparse hairs; medial lobe of the uncus trapezoid with median incision suggesting a fusion of lobes, its tip notched at the exit of the aedeagus; clasper protruding from below uncus bearing two spines, of which the medial one is relatively longer and curved with its tip directed dorsolaterally; lateral spine of clasper shorter and daggerlike, with its tip slightly curved laterally; the upper lobe of pygofer is rudimentary and less prominent than the basal lobes; distinctly protruding lower basal pygofer lobes with its base located in paramedian position and with their apices directed posterolaterally (divergent); the depression between the bases of the basal lobes of pygofer on each side deep and divergent ( Figs. 6A–B ); aedeagus with its proximal two-fifth wider, the rest slightly angulated and tapers finely to its tip ( Fig. 6D ). In dorsal view, apex of distal shoulder of the pygofer reaches middle of the height of anal style, and dorsal beak of pygofer is small ( Fig. 6C ).

Description of females. The colour and structure of the females are generally as in males, the major differences are mentioned below. The wing measurements and those of the head and thorax are equal, or only marginally small- er. The length of abdomen is, however, much shorter (AL—15.60±1.39; API—110.52±13.57); operculum small (OPL—4.7±0.45; OPI—27.52±2.82) but more triangular than in males with a concave anterolateral margin, widely separated, not meeting on midline and the medial border ends at the level of the meracanthus (mc), the posterior margin just reaches the level of the distal end of sternite II; timbal covers absent; sternite VII with its midventral part forming a notch; genitalia with an acute dorsal beak of sternite 9 is much longer and prominent than in males; it reaches just distal to the level of the protruding ovipositor sheath ( Figs. 3B , 4B–D ).

Variation. The external variation is generally restricted to the size of the insect. Males have a FL of 40.8± 2.14 mm and females FL—33.75± 0.35 mm. The Gastral Index (GI) is 62.49± 0.17 in males and 89.07± 10.56 in the female. The variations in venation are more commonly aberrations that are seen on wings of the same individual across the sides. There are occasional variations in the number of apical cells in the forewings, instead of the usual 8, there may be 9 apical cells, because of splitting of apical cell 7. The infuscations are generally consistent. It appears that the calls are not different across the Anamalai and Agasthyamalai populations. However, the male genitalia was slightly variable: the small mid-dorsal beak of the pygofer seen in the holotype ( Fig. 6C ) was absent and replaced by an invagination, the basal lobe of pygofer thinner, the depression between the bases of the basal lobes of pygofer is U-shaped and the posterior fenestra was round in most of the sampled Agasthyamalai population, while the dorsal beak was like a lingular extension, basal lobes stouter, bases of the basal lobes of pygofer separated by V-shaped depression and the posterior fenestra is oval-shaped in the Anamalai hills population and the holotype is from this region. In males (n=6), the abdominal length (AL—23.20±1.30) and the width at the base of tympanal cover (AL—13.80±1.30) were marginally variable. The operculum length was relatively constant (OPL—8.00±0.94), while the rostral length varied slightly (RL—11.2±1.64). In females (n=4), the abdominal length was a little variable (AL—15.60±1.39), but the abdominal width was relatively constant (AW—12.50±0.71). The rostral length (RL—13.00±0.71) and the opercular length (OPL—4.7±0.45) were only slightly variable. The variation in the anterior body length was minimal (ABL males—17.60±1.39; females—17.10±0.96), compared to the total body length (TL males—40.8±2.14; females—32.7± 1.04). In the males relative position of uncus is variable probably according to the mated status, the tenerals having the uncus almost inside the pygofer ( Fig. 6A ), and in mated males they are conspicuously everted out ( Fig. 5F ).

Distribution. Agasthyamalai Hills of Trivandrum and Kollam districts, Kerala at 100–900 m above sea level (a.s.l); Pala in Kottayam District, Kerala, 100m a.s.l; Periyar Tiger Reserve & Rajakumari, Idukky district, Kerala, 300–950 m a.s.l; Kotagiri, Nilgiris District, Tamil Nadu 800–850 m a.s.l, and Coorg, Karnataka 600–750 m a.s.l. Hence, the species is found both north & south of Palghat gap from 100-900 m a.s.l ( Fig. 1 ).

Ecological notes. The species is very common to abundant in homesteads, edges of tea estates, coffee plantations, and jungles of 500–1200 m elevation ( Fig. 7A&B ). They call during the late afternoon hours and are usually heard calling from the bases of trees up to 8 metres. The call is very loud and the deafening call is unmistakable. A group of males will be calling from a patch of the forest and another group of males will call from a different patch as the first batch of calls dies down. They will stop calling as one approaches and does not fly away unless disturbed. They sit well camouflaged against the green moss and dark bark of trees. Both sexes are attracted to tube lights and were seen diving into shops and houses at dusk. The main activity is centred around the southwest monsoon from May to July. Calls are more commonly heard during overcast days and dusk. The call is short and lasts less than a minute, it is a series of rapidly increasing crescendo notes and the time interval between these notes becomes lesser and lesser as the call progresses ( Fig. 8A&B ).

Diagnosis. By its agreement with the diagnostic criteria of Duffels & Hayashi (2006), the new species is a member of the P. linearis group. It is very similar to P. linearis in its general coloration but differs consistently in the structure of the male genitalia. The basal lobe of pygofer in the new species is directed posterolaterally, hence divergent, while it is directed posteromedially, hence convergent in P. linearis . The tip of the basal lobe of the pygofer is acute but the tip rounded, while, the tip of the basal lobe of the pygofer is blunt and rounded in P. linearis . The claspers with relatively thinner and longer spines in P. pseudolinearis , while they are short and thicker in P. linearis . The dorsal beak of the pygofer reaches only the middle of the height of anal styles in the new species while in P. linearis it reaches the height of anal styles.

Morphometric indices were useful in separating the new taxon from true P. linearis . P. linearis is a large insect compared to P. pseudolinearis (ABL 20 vs. 17; AL 30 vs. 22; TL 50 vs. 39). The AW was more in P. linearis (17 vs. 13.5). The forewing length and width were much longer in P. linearis in comparison with P. pseudolinearis . But the aspect ratio of the forewing was smaller in comparison (FAR 294.44 vs. 326.67). HW length is slightly more in P. pseudolinearis (25 vs. 22). The IWR was higher in P. linearis (240.91 vs. 196). The FI was higher in P. pseudolinearis (288.24 vs. 265), signifying relatively longer wings in comparison with the ABL. Cephalic measurements were slightly higher in P. linearis and CI was higher in P. pseudolinearis (333.33 vs. 275). Eye length (3mm in both) but ocular index was higher in P. pseudolinearis (30 vs. 27.27). PI was higher in P. pseudolinearis (280 vs. 233.33). MI was marginally higher in P. pseudolinearis (122.22 vs. 120). API was higher in P. pseudolinearis (77.27 vs. 66.67). GI was higher in P. pseudolinearis (61.36 vs. 56.68).

The new taxon is distinguished easily from other Pomponia species reported from India. The mediocubital crossvein (m-cu) of apical cell 7 is strongly infuscated in P. pseudolinearis , while it is absent or inconspicuous on P. cinctimanus , P. ramifera , and P. urania . Furthermore, the study of high-resolution images of holotype, # 1009390 BMNH (E), P. urania has shown that its FW apical cell 5 less than half the length of its apical cell 6; while it is always more than half of the apical cell 6 in P. cinctimanus , P. ramifera and P. pseudolinearis . P. cinctimanus has m-cu of basal apical cell 7 slanting with respect to longitudinal vein of apical cell 8 (making an obtuse angle), while in P. ramifera the m-cu is vertical (right angle); while in the new species P. pseudolinearis it is curved outwards making an acute angle with apical cell 8 longitudinal vein. Other taxa that are found in India are discussed below with those from the rest of Southeast Asia from the P. linearis species group.

With regards to other extralimital species of P. linearis group, the new taxon can be differentiated based on the structure of the basal lobes of the pygofer and the relative lengths of the medial and lateral spines of the claspers. In P. pseudolinearis the basal pygofer lobes have distal ends that are divergent, this is in sharp contrast to the convergent basal pygofer lobes in P. linearis , P. tuba , P. ponderosa , P. dolosa , P. backanensis , P. minilinearis , and possibly other species of P. linearis species complex like P. cinctimanus , P. ramifera , and P. urania ( Duffels & Hayashi 2006; Lee, 2009; Boulard 2013; Pham et al. 2015). Pomponia brevialata has distinctly shorter wings and claspers with two acute spines of subequal length ( Pham et al. 2015), while in the new species uncus bears two spines, of which the medial one is longer and curved with its tip directed dorsolaterally; lateral spine of clasper short and dagger-like, with its tip, slightly curved laterally. Forewing infuscations on the hind margin of vein M 1 are about as long as other marginal infuscations in P. pseudolinearis , while it is nearly twice as long as other marginal infuscations as per Lee (2009) in P. lineari s, P. tuba , and P. ponderosa . All longitudinal veins of FW are infuscated in P. pseudolinearis while it is not distinctly infuscated P. dolosa as per Lee (2009). The well-developed basal pygofer lobe in paramedian position (not lateral) of P. pseudolinearis delineates it from the other members of the Pomponia linearis group but not belonging to the P. linearis species complex. These species have the basal pygofer lobes small, placed laterally adjacent to the sides of the upper lobe of pygofer. The species under this cluster are P. zakrii , P. langkawiensis , P. subtilita , P. piceata , P. pornnapaae , and P. daklakensis ( Lee, 2009; Boulard 2013; Pham et al. 2015).

Pomponia cyanea seen in the southern Western Ghats is easily diagnosed from P. pseudolinearis by its larger size, distinct call, and the structure of the male claspers which are broad & rounded and the postclypeus missing the pale transverse band. The uncus with the medial and lateral spines in P. pseudolinearis differentiates it from P. secreta and P. zebra both of which have broad lobes instead of these spines. Pomponia solitaria from Andaman & Nicobar Islands and P. surya from Mussoorie have their FW almost immaculate with only basal veins of apical cells 2 and 3 cells infuscated, while all the apical cells except apical cell 6 are infuscated in P. pseudolinearis . In addition, the opercula are very small, inwardly and outwardly oblique, with apices broadly convex in P. solitaria , and the opercula short but placed longitudinally, apex broadly convex in P. surya ; while it is short with lateral margin almost straight, angle curved, and medial margin oblique in P. pseudolinearis .

Figures

FIGURE 1. Map showing the type locality and spot records of Pomponia species from the southern Western Ghats. Modified from Apple Maps, Copyright 2012–2020 Apple Inc.

FIGURE 3. Pomponia pseudolinearis sp. nov.: A, Image of holotype (THRG 0033) dorsal view. B, Image of a paratype female (THRG 0032) from the same locality.

FIGURE 4. Pomponia pseudolinearis sp. nov.: A, venation of holotype. B, venation of paratype (THRG 0032) female from the same locality. C, ventral view of terminal abdominal segments of the female. D, lateral view of terminal abdominal segments of female, E, dorsolateral view of the left femur of male (holotype) showing the primary and secondary spines.

FIGURE 5. Pomponia pseudolinearis sp. nov.: Images of live insect (THRG 0036), taken as a paratype from Rajakumari, Idukki, District, Kerala. A, lateral view of head and thorax. B, ventral view of head and clypeus. C, ventral view of the whole insect. D, dorsal view of the whole insect. E, lateral view of the whole insect. F, genitalia with the everted uncus.

FIGURE 6. Pomponia pseudolinearis sp. nov. male genitalia (THRG 0036): A, ventroposterior view. B, lateral view. C, dorsal view. D, lateral view of the aedeagus.

FIGURE 7. Habitats of Pomponia species from southern Western Ghats, A&B Pomponia pseudolinearis sp. nov. and C&D P. cyanea: A, Sub-tropical evergreen forests. B, higher canopies of Sub-tropical evergreen forests. C, Montane temperate shola forests. D, stunted trees of Montane temperate shola forests. Photo A&B by Kalesh Sadasivan, C&D by Raghuram.

FIGURE 8. Pomponia pseudolinearis sp. nov. song from Rajakumari, Idukki District, Kerala, southern Western Ghats, temporal representation (relative dB vs. time): A, full-length song; B, two representative calls from the song sampled.