Cardiodactylus minuta 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 : 250-254

Cardiodactylus minuta Bhowmik, 1981

( Figs 5D–F , 6C, 6D , 7D–F , 8–11 )

Cardiodactylus minuta Bhowmik, 1981: 44 — Otte, 2007a: 343.

Type material. Holotype: PAPUA NEW GUINEA • ♂ [examined]; New Guinea , Mafulu, alt. ca., 1219 m; i.1934; L.E. Cheesman leg.; NHMUK ( Fig. 8 ).

New material examined. INDONESIA • 2♀; Papua, Nimbokrang, secondary forest near lodge, 3h W Jayapura (GPS23 Pa 12); S02.57199 E140.09897, 133 m; 2–3.x.2023; TR23-141, day; Daawia et al. leg.; KSP • 1♀, 3♂; same information as previous; TR23-144, TR23-152; night; Daawia et al. leg.; KSP • 5♀, 2♂; Papua, base Mounts Cyclops, S. near waterfall (GPS23 Pa 1); S02.54479 E140.51254, 280 m; 15.ix.2023; TR23-24 (2♀), TR23-41 (1♀), TR23-84 (1♂; call recording Take Pap 300), TR23-85 (2♀, 1♂); night; Daawia et al. leg.; KSP • 8♀, 1♂; Yapen I., Karopai, secondary forest near village; S01.85559 E136.19408, 56 m (GPS23 Pa 6); 21–23.ix.2023; TR23-51 (5♀), TR23-55 (1♂, call recording on video), TR23-69 (3♀); night; Daawia et al. leg.; KSP • 2♂; same information as previous: TR23-64; day; Daawia et al. leg.; KSP • 3♀; Yapen I., Ariepi village, secondary forest near river, S. Mambo (GPS23 Pa 9); S01.82665 E136.13297, 48 m; 26.ix.2023; TR23-99; night; Daawia et al. leg.; KSP • 1♀; Yapen I, Kapanani, secondary forest on slope near village (GPS23 Pa 11); S01.83673 E136.29596, 134 m; 28.ix.2023; TR23- 122; night; Daawia et al. leg.; KSP .

Remarks. Based on new material, we can redescribe the species and describe the calling song.

New diagnosis. Cardiodactylus minuta is very similar to Cardiodactylus niugini Dong & Robillard, 2016 in the general habitus and colouration pattern, and the pseudepiphallus having a posterior apex spatulate, but C. minuta differs by: (1) the lateral side of FW almost entirely yellow ventrally (instead of having a brown ventral margin in C. niugini ); (2) the male FW having its mirror (d1) more slender at the posterior end separated by three accessory veins (instead of two in C. niugini ), (3) the apex of pseudepiphallus with its apical end more tongue-shaped, its apex more rounded (instead of more fan-shaped and apex broad in C. niugini ), (4) the pseudepiphallic parameres with their posterior lobe slightly longer and more slender and anterior lobe having its apex bent. The calling song of C. minuta also differs from that of C. niugini by the call structure being an echeme composed of more closely-spaced syllables, frequency spectrum more tonal and a higher dominant frequency. The species is also similar to Cardiodactylus nigris Bhowmik, 1981 and Cardiodactylus pictus Saussure, 1878 in the general habitus and colouration patterns, but differs clearly from C. nigris by the lateral side of FW entirely yellow, and by the shape of the posterior apex of pseudepiphallus and of the pseudephallic parameres.

Redescription. Size average for species group, general colouration dark brown ( Figs 8 , 9 ). Head ( Figs 5D–F ): Dorsum brown with four wide longitudinal dark brown bands, almost fused with one another, punctuated anteriorly; and with faint brown band posterior to eyes. Eyes large and prominent, orange brown with a dark longitudinal band in living individuals. Fastigium dark brown, about 1.8 times as wide as scape, its margins yellow. Antennae yellow brown. Scapes light brown banded with dark brown. Face mostly yellow brown, with two black spots between scapes ventrad of median ocellus; with two small fenestrae beneath these spots. Clypeus cream coloured with median part dark brown; labrum mostly yellow brown; maxillary palpi with segments yellow brown, with few dark brown patterns. Pronotum ( Figs 5A, 5C ): Dorsal disk brown, almost rectangular, about twice as wide as long, densely setose, with several symmetrical sutures mottled with dark brown; anterior margin faintly concave, posterior margin slightly bisinuate. Lateral lobes dorsal third dark brown, forming a longitudinal dorsal band; ventrad of dorsal band generally yellow brown. Legs yellow brown, faintly mottled with dark brown; FIII knee and TIII dark brown. FWs exceeding apex of abdomen, generally unicolourous brown with some veins slightly lighter or darker. CuA/M/R areas without whitish sclerotization anteriorly ( Figs 6C , 9 ). Hind wings well surpassing FWs, forming an 8.8-mm grey-brown tail ( Fig. 9 ). Cerci shorter than hind legs, grey brown.

Male. FW venation ( Fig. 6C ): CuP absent. 1A straight and transverse, with a notch anterior to angle; angle almost 90°. Harp narrow and elongate, with one W-shaped oblique vein and 1–2 faint anterior ones. Cell c1 very elongated, somewhat sinuated rectangular; c2 large, pentagonal. Mirror (d1) large, comma-shaped, about as long as harp, its narrower posterior part divided by three transverse accessory veins. Cell d2 small compared to d1, divided with numerous accessory veins. Sc with 6 projections.

Male genitalia ( Figs 7D–F ): Pseudepiphallus narrowed at mid-length, forming a neck somewhat stout; posterior part forming almost right angle with rest of sclerite laterally; dorsal part of narrowed posterior part with two thin and narrow ridges forming a shallow gutter; dorsal ridge straight in lateral view; posterior apex in dorsal and ventral views somewhat spatulate, its middle part distinctly broader than base, then slightly narrow, apical third broaden into obtuse apex. Anterior part of pseudepiphallus concave, with two lateral rounded triangular extensions pointing dorsally perpendicular to length of pseudepiphallus in lateral view and with apex rounded. Rami long and strong, with oval preapical plates and long apical stems faintly convergent. Pseudepiphallic parameres trilobate: anterior lobe triangular, slender, slightly bent at acute apex; median lobe stout, strongly sclerotized, apex obtuse; posterior lobe longest, slender and triangular, apex subacute. Ectophallic arc complete, curved posteriorly. Ectophallic apodemes lamellate, not reaching rami preapical plate, slightly divergent. Ectophallic fold with strong lateral sclerites, widened near membranous apex. Endophallic sclerite small, with small posterior expansion and short latero-ventral arms; endophallic apodeme with long lateral lamellae and a small dorsal crest.

Female. FW colouration mostly brown,veins typically red brown( Fig.6D ).Dorsal field with8strong longitudinal veins. Lateral field with 7 yellow projections of Sc, their bases dark brown, and 4 more ventral longitudinal veins. Ovipositor very short, shorter than FIII; apex dorsal edge denticulate.

Juveniles. Distinctive colouration yellow finely mottled with dark brown in most instars; dorsal part of abdomen with a median dark brown spot near base of abdomen and 6 pairs of dark spots along abdomen ( Fig. 11D ).

Measurements (3♂, 4♀; in mm, mean in brackets). ♂: BL = 18.1–19.0 (18.6), PronL = 2.2–2.3 (2.3), PronW = 4.2–4.3 (4.2), FWL = 13.3–14.5 (13.8), FWW = 3.9–4.1 (4.0), HWT = 7.8–8.3 (8.1), FIIIL = 13.2–15.8 (14.4), FIIIW = 3.4–3.9 (3.7), TIIIL = 12.8–15.3 (13.7); ♀: BL = 18.2–22.3 (20.3), PronL = 2.4–2.7 (2.6), PronW = 4.1–5.0 (4.5), FWL = 15.1–16.2 (15.5), FWW = 3.7–5.0 (4.1), HWT = 6.3–7.8 (7.0), FIIIL = 13.9–16.9 (15.4), FIIIW = 3.0–4.2 (3.9), TIIIL = 14.0–15.4 (14.7), OL = 10.9–12.7 (11.6).

Type locality. Papua New Guinea: Mafulu [S8.408159°, E147.307687°] ( Bhowmik, 1981) .

Distribution. Papua New Guinea.

Calling song ( Fig. 10 ). The calling song of C. minuta is composed of echemes, often isolated in time, but that can aggregate to form an echeme-sequence of three to 15 echemes of increasing amplitudes. In such case, the last echeme can be twice longer than the other echemes. On average, the echeme duration is 1.4±0.5 s made up of 48±18 syllables. The average syllable duration is 12.7±3.3 ms. On rare occasion, one to four much shorter syllables (3–5 ms instead of 10–15 ms) occur in the second half of the echeme. The average syllable period is 28.99±2.33 ms. The frequency spectrum is made up of harmonics; the dominant frequency is 18.64±0.87 kHz, and does not correspond to the fundamental frequency, but to the third harmonic. The fundamental frequency is around 6–7 kHz and has a higher energy than the second harmonic.

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 8. Cardiodactylus minuta Bhowmik, 1981 male holotype in lateral view.

FIGURE 9. Cardiodactylus minuta Bhowmik, 1981 male (A, B) and female (C, D) habitus in dorsal (A, C) and lateral (B, D) views. Scale bar: 2 cm.

FIGURE 10. Cardiodactylus minuta Bhowmik, 1981 calling song: oscillogram of a series of calling songs made up of 11 echemes (A), spectrograms of an echeme (B) and a syllable (C), and power spectrum of a syllable (D).

FIGURE 11. Cardiodactylus minuta Bhowmik, 1981 in their natural environment: male (A), female ovipositing (B), a mating pair (C) and a juvenile (D).