Cardiodactylus nigris Bhowmik, 1981

Depraz, Emilien, Tan, Ming Kai, Rahandra, Erlani Febrida, Ramandey, Eunice R. P. F. & Robillard, Tony, 2024, Taxonomy and calling songs of some species of Cardiodactylus (Gryllidae, Eneopterinae, Lebinthini) from New Guinea, Zootaxa 5551 (2), pp. 242-262 : 254-260

Cardiodactylus nigris Bhowmik, 1981

( Figs 5G–I , 6E , 7G–I , 12–15 )

Cardiodactylus nigris Bhowmik, 1981: 45 — Otte, 2007a: 343.

Type material. Holotype: PAPUA NEW GUINEA • ♂ [examined]; New Guinea , Mt Torcella, 12 miles east of Afua; 3–8.iv.1936; G.O. Moore leg.; NHMUK ( Fig. 12 ).

New material examined. INDONESIA: 3 juveniles ; Papua, Keerom, Ubigau, gallery forest along river (GPS23Pa3); S02.94828 E140.70859, 110 m; 17.ix.2023; TR23-18; night; Daawia et al. leg.; KSP • 3♂, 6♀; Yapen I.; Ambaidiru, secondary habitat along road (GPS23Pa5b); S01.75441 E136.17958, 699 m; 20.ix.2023; TR23-36, TR23-37, TR23-59; night; Daawia et al. leg.; KSP • 2♂, 2♀; Yapen I., Karopai, secondary forest near village (GPS23Pa6); S01.85559 E136.19408, 56 m; 21–23.ix.2023; TR23-69; night; Daawia et al. leg.; KSP • 1♂; 2♀; Yapen I., Mambo, near coffee plantation; S01.76969 E136.15408; 22.ix.2023; TR23-70, TR23-93; Daawia et al. leg.; KSP • 4 juveniles; Yapen I., Samber Mt. along road nr forest on slope (GPS23Pa7); S01.73909 E136.31322, 930 m; 23.ix.2023; TR23-77; night; Daawia et al. leg.; KSP • 1♂; Yapen I., Mantembu village , secondary area along river (GPS23Pa8); S01.84270 E136.23038, 167 m; 25.ix.2023; TR23-90; night; molecular sample C269; Daawia et al. leg.; KSP .

Remarks. Based on new material, we are able to redescribe the species and describe its calling song. The species is characterized by variation of melanisation, some specimens being almost black, while others are redbrown. Similarities in details of colouration, male genitalia and FW venation led us to consider these differences as intraspecific variation.

New diagnosis. Cardiodactylus nigris is most similar to Cardiodactylus pictus in terms of general habitus and small size, colouration pattern and male FW venation and the pseudepiphallus having a posterior apex rectangular. However C. nigris shows the following distinctive characters: (1) the general colouration is more contrasted, dark orange brown to almost black, with a few yellow parts, including a narrow yellow band on lateral field of FWs; (2) the fastigium is yellow and the face has a darker shade of brown (fastigium dark brown and face yellow in C. pictus ) (3) the pronotum dorsal disk has a broader pair of cream-coloured longitudinal bands, (4) the pseudepiphallic parameres with their posterior and anterior lobes of equal size (instead of the anterior one distinctly broader and stouter than the posterior one), (5) the endophallic sclerite is very small and almost not extended anteriorly.

Redescription. Size average for species group, general colouration contrasted, mostly dark brown with small areas vivid yellow or cream coloured ( Figs 12 , 13 ). Head ( Figs 5G–I ): Dorsum brown with four wide longitudinal black bands, median ones almost fused with one another, punctuated anteriorly to form two dark brown spots; and with faint brown band posterior to eyes. Eyes large and prominent, dark pink in living individuals. Fastigium yellow brown, 1.8 times as wide as scape, its margins yellow. Antennae dark brown with two with rings. Scapes mostly dark brown. Face mostly brown or yellow brown, area between scapes with a black band below median ocellus ( Figs 5H, 5I ). Clypeus brown; labrum mostly cream coloured; maxillary palpi with segments brown with dark brown bands. Pronotum ( Figs 5G, 5I ): Dorsal disk almost rectangular, about twice wider than long, with broad lateral cream-coloured longitudinal bands, median area mottled with dark brown to black patterns anterior margin concave, posterior margin slightly bisinuate; lateral lobes with dorsal margin black, ventral half dark brown with a faint brown patch. Legs dark brown to black, faintly mottled with dark brown; FIII knee and TIII dark brown. FWs exceeding apex of abdomen; dorsal disk generally unicolourous brown; lateral field with just ventrad of Sc having narrow black longitudinal band, ventrad of this is thicker and cream-coloured longitudinal band, ventral half brown to dark brown ( Figs 6E , 12 , 13 ). Hind wings well surpassing FWs; tail 8.8 mm, grey brown. Cerci shorter than hind legs, grey brown.

Male. FW venation ( Figs 6E , 12C ): CuP absent. 1A straight and transverse, with very faint notch anterior to angle; angle slightly more than 90°. Harp very slender and elongate, with one W-shaped oblique and 1–2 faint anterior ones. Cell c1 very elongated, somewhat sinuated rectangular; c2 large; mirror (d1) very large and broad, inverted-pyriform, slightly shorter than harp, at narrower posterior part divided by one transverse accessory vein, this vein slightly curved; d2 wide, somewhat rectangular, not divided by accessory veins. Sc with 6 projections.

Male genitalia ( Figs 7G–I ): Pseudepiphallus narrowed at mid-length, this neck somewhat stout; posterior part forming almost right angle with rest of the sclerite laterally; dorsal part of narrowed posterior part with two thin and narrow ridges forming a very shallow gutter, ridge in lateral view mostly straight to slightly sinuated; posterior apex in dorsal and ventral views rectangular, almost square. Anterior part of pseudepiphallus concave, with two lateral extensions, in lateral view elongated, towards apex slightly curved anteriorly with apex truncated. Rami long and strong, with slender preapical plates and long apical stems slightly convergent. Pseudepiphallic parameres trilobate: posterior and anterior lobes triangular with subacute apices, median lobe broadly rounded, stout and more sclerotized. Ectophallic arc complete, curved posteriorly. Ectophallic apodemes long and slender, reaching anterior end of rami, slightly convergent but at middle subparallel to one another. Endophallic fold with strong lateral sclerites, widened near membranous apex. Endophallic sclerite very small, with small posterior expansion and short roundish latero-ventral arms; endophallic apodeme weakly sclerotized with both short lateral lamellas and small dorsal crest.

Female. FW colouration mostly dark brown, veins typically yellow ( Fig. 15C ). Dorsal field with 8 strong longitudinal veins. Lateral field with 6 projections of Sc and 4 more ventral veins. Ovipositor slightly shorter than FIII; apex dorsal edges denticulate.

Juvenile. Early instars with a very characteristic grey colouration with a black transverse stripe on dorsal part of abdomen, this stripe containing a thin line of red; leg dark brown; antennae black with irregular white rings.

Measurements (4♂, 1♀; in mm, mean in brackets). ♂: BL = 16.7–18.3 (17.3), PronL = 2.2–2.5 (2.2), PronW = 3.9–4.4 (4.1), FWL = 12.6–13.9 (13.5), FWW = 3.3–3.7 (3.5), HWT = 6.7–8.4 (7.7), FIIIL = 14.4–16.0 (15.4), FIIIW = 3.0–3.8 (3.5), TIIIL = 14.7–15.3 (15.3) mm. ♀: BL = 18.2, PronL = 2.6, PronW = 4.2, FWL = 13.9, FWW = 3.6, HWT = 7.9, FIIIL = 15.4, FIIIW = 2.9, TIIIL = 14.1 mm; OL = 12.6.

Type locality. INDONESIA, West Papua (= D. N. Guinea), Torcella Mt. , 12 mi East of Afua [S3.370506, E142.745414] ( Bhowmik, 1981) .

Distribution. Northern New Guinea, including Yapen I. and Biak I.

Calling song ( Fig. 14 ). The calling of C. nigris song is composed of short echemes lasting 1.07±0.1 s. Each echeme is made up of 87±6 syllables. The average syllable duration is 5.0±0.3 ms and the syllable period is 7.2±0.1 ms. The frequency spectrum is made up of harmonics, the dominant frequency is 17.90±0.12 kHz, does not correspond to the fundamental harmonic, but to the third harmonic. The fundamental frequency is 6 kHz.

The calling song activity seems to be more intensive during the night. On average, the call length and the number of echemes per call are higher during the night than the day (148.97±56.87 s vs. 83.08 ± 39.09 s and 15±5 echemes vs. 9±4 echemes, respectively).

Figures

FIGURE 5. Cardiodactylus javarere Otte, 2007a (A–C), Cardiodactylus minuta Bhowmik, 1981 (D–F) and Cardiodactylus nigris Bhowmik, 1981 (G–I): head and pronotum in dorsal view (A, D, G); face in anterior view (B, E, H); anterior part of body in lateral view (C, F, I). Scale bars: 2 mm.

FIGURE 6. Cardiodactylus javarere Otte, 2007a (A, B), Cardiodactylus minuta Bhowmik, 1981 (C, D) and Cardiodactylus nigris Bhowmik, 1981 (E) male (A, C, E) and female (B, D) FWs in dorsal view. Scale bars: 2 mm.

FIGURE 7. Cardiodactylus javarere Otte, 2007a (A–C), Cardiodactylus minuta Bhowmik, 1981 (D–F) and Cardiodactylus nigris Bhowmik, 1981 (G–I) male genitalia in dorsal (A, D, G), ventral (B, E, H) and lateral (C, F, I) views. Scale bars 1 mm.

FIGURE 12. Cardiodactylus nigris Bhowmik, 1981 male holotype in dorsal (A) and lateral (B) views; FW in dorsal view.

FIGURE 13. Cardiodactylus nigris Bhowmik, 1981 male habitus in dorsal (A) and lateral (B) views. Scale bar: 2 cm.

FIGURE 14. Cardiodactylus nigris Bhowmik, 1981 calling song: oscillogram of a series of calling songs made up of 12 echemes (A) and an echeme followed by an isolated syllable (B), spectrograms of an echeme (C) and an isolated syllable (D), and power spectrum of a syllable (E).

FIGURE 15. Cardiodactylus nigris Bhowmik, 1981 in their natural environment: adult male in dorsal (A) and lateral views (B), female (C) and juvenile (D).