Varitrella (Cantotrella) fuscoirrorata ( Chopard, 1925 ) Tan & Salvador & Sabang & Bahoy & Nuñeza & Robillard, 2023

Tan, Ming Kai, Salvador, Jewel Anne G., Sabang, Aira Mae M., Bahoy, Daphne Cayle M., Nuñeza, Olga Macas & Robillard, Tony, 2023, Taxonomy and bioacoustics of little-known Grylloidea crickets (Orthoptera, Ensifera) from Mindanao, Philippines, Zootaxa 5323 (3), pp. 301-348 : 317-322

Varitrella (Cantotrella) fuscoirrorata ( Chopard, 1925) comb. nov.

( Figs 17–19 )

Madasumma fuscoirrorata Chopard, 1925: 320 — Chopard, 1968: 372

Specimen examined. Holotype: PHILIPPINES • ♁; Mindanao, Iligan; coll. C.F. Baker; MNHN-EO-ENSIF6695

New specimens examined. PHILIPPINES • 1♁; Mindanao, Agusan del Sur, Talacogon, Barangay Marbon ; N8.3963847, E125.8110506; 11 May 2022, 22h04; on the foliage of Zea mays ; coll. M. Salvador, J.A. Salvador, B. Beramo; 30JAS952 ( PNM) ( Fig. 17A ) • 1♁; Mindanao , Balingoan , Barangay Mapua , Mimbilisan Protected Landscape ; N8.948889, E124.865278, 450–500 m.a.s.l; 2 April 2023, 19h00; open area outside secondary forest, on a surface of a bush; coll. A.M. Sabang & D.C.M. Bahoy; A205 ( ZRC) ( Figs 17B, 17C )

Remarks. This species was previously described based on a female from Iligan (Lanao del Norte) in Mindanao (MNHN-EO-ENSIF6695). Our male specimens from Mindanao resemble the female holotype by the pronotal dorsal disk with a characteristic hourglass-shaped dark brown pattern and the spotted patterns on the legs. Given that our male specimens were collected from Agusan del Sur and Balingoan, it will not be surprising that this species is more widely distributed across Mindanao. Here, the male is described for the first time, but whether our male specimens are truly Varitrella (Cantotrella) fuscoirrorata can still afford further testing and verification.

Diagnosis (new). The male genitalia of Varitrella (Cantotrella) fuscoirrorata is most similar to Varitrella quadrata (Haan, 1842) from Java by the ectophallic fold with its apex somewhat surpassing both the lateral lobes and with the emargination between both lateral lobes truncated; but differs by the pseudepiphallus with the dorso-anterior pseudepiphallic spine strongly sclerotized but small, and with its acute apex (absent in Varitrella quadrata ); by the pseudepiphallus in profile view with its latero-apical lobular parts truncated, and with the dorso-posterior angle nearly right-angled and without a dorso-apical process; and by the ectophallic fold shaft-liked with lateral margins somewhat parallel throughout its length.

From Philippines congeners, Varitrella (Cantotrella) fuscoirrorata differs from Varitrella (Cantotrella) saussurei (Stål, 1877) , Varitrella (Cantotrella) bakeri ( Chopard, 1925) , Varitrella (Cantotrella) conspersa (Stål, 1877) and Varitrella (Cantotrella) variabilis Gorochov, 2006 by the presence of the small dorso-anterior pseudepiphallic spine and the absence of a large dorso-apical process at the latero-apical lobular parts; as well as by the shape of ectophallic fold. From Varitrella mindoroensis Gorochov, 2006 by the distinctly different shape of male genitalia; from Varitrella palawanensis Gorochov, 2006 by dorso-anterior pseudepiphallic spine smaller and shorter and latero-apical lobular parts of pseudepiphallus in profile view more truncated, and the shape of ectophallic fold.

Redescription. Habitus medium sized, generally brown to dark brown. Head in dorsum brown with medial part of posterior third dark brown; finely pubescent, especially posterior of eyes. Fastigium in dorsal view dark brown. Rostrum about 0.9 times as wide as scapes, finely pubescent; with apex in dorsal view truncated and margin cream-coloured ( Fig. 18A ). Eyes in dorsal view faintly projected anteriorly ( Fig. 18A ). Median ocellus small and round; lateral ocelli round and larger than median ocellus, in anterior view located dorsad of scapes close to median ocellus ( Fig. 18B ). Maxillary palpi with apical segment longest, particularly pubescent (compared to other segments), somewhat pyriform with rounded apex; with subapical segment cylindrical and expanding apically; with third segment slender and cylindrical and slightly longer than subapical segment ( Fig. 18C ). Gena and posterior of eye in profile view brown with tint of dark patterns ( Fig. 18C ). Face in anterior view ca. 1.1 times as tall as wide; cream-coloured between antennal sockets, with dark transverse band ventrad of antennal sockets; mouthparts mostly yellow brown ( Fig. 18B ). Pronotal disk brown, about 1.3 times as wide as long, faintly widening posteriorly (posterior margin 1.2 times as wide as anterior margin); with small black spots; in middle with hourglass-shaped dark-brown pattern but with indistinct margin; finely and densely pubescent ( Fig. 18A ). Pronotal disk with anterior margin broadly concave and with black and cream-coloured spots; disk with posterior margin faintly angularly convex with fewer contrasting-coloured spots ( Fig. 18A ). Pronotal lateral lobe 1.6 times as long as high; densely and finely pubescent; in dorsal third with a longitudinal black band, otherwise brown with black spots; margins brown ( Fig. 18C ). Metanotal gland absent. TI swollen; with inner tympanum slit-like; with outer tympanum open and having oval tympanal membrane (smaller than the slit of inner tympanum). TIII with 6 inner and 5 outer long subapical spurs, 3 inner and 2 outer apical spurs; with 1–4 spines between spines; many numerous spines before most proximal spurs; and with inner spurs (including apical spurs) longer than corresponding outer ones. Legs generally cream-coloured with numerous small dark spots; FIII with ventral margin having distinct dark bands, with posterior end darkened and knee dark coloured; TIII pale brown with numerous small dark-brown spots, spurs generally pale-coloured with red-brown apices. Thoracic and abdominal tergites and sternites generally cream-coloured with small faintly-dark spots.

Male. FW covering abdomen and barely surpassing apex of FIII ( Fig. 17 ). Colouration: yellow brown. Dorsal field yellow brown with veins at basal area, proximal part of region of chords dark-coloured; with veins around plectral area (pl) white; and with white spot between disto-lateral edge of mirror and stock of MP+CuA1 ( Fig. 18D ). Lateral field paler, pale brown with blackish marks near Sc between branches of Sc. Between R and M cream-coloured and Sc and R dark coloured ( Fig. 18D ). Venation: diagonal straight, with 5 oblique veins in harp area; mirror 1.6 times as long as wide, dividing vein typical of subgenus ( Fig. 18D ). Lateral field with around 16 branches on Sc ( Fig. 18E ). Hind wings clearly surpassing FWs ( Fig 17 ).

Subgenital plate with lateral margin tapering into subacute apex; with medial carina running longitudinal which produce into small lobe at apical margin ( Fig 18F ).

Male genitalia as shown in ( Fig. 19 ): Pseudepiphallus [epiphallus] stout, in profile view tall and broad. Pseudepiphallus with dorso-anterior pseudepiphallic spine (ds) strongly sclerotized but small with acute apex; with two smaller spinules posterior of the spine; in profile view pointing dorsad. Pseudepiphallus with posterior end diverged and produced into two latero-apical lobular parts (al). Pseudepiphallus in dorsal view: broad, with apex narrowly obtuse; between latero-apical lobules deeply V-emarginated. In profile view: with posterior part truncated, without dorso-apical spinule but along dorsal margin with a few small spinules and short fine setae; dorso-posterior angle nearly right-angled, ventro-posterior angle curved. Pseudepiphallic paramere [ectoparamere] elongated, tapered abruptly into a slender and curved hooked-like apical third with apex acute, and pointing ventrad posteriorly. Ectophallic fold [rachis] shaft-liked, with lateral margins somewhat parallel throughout length, rather long, slightly surpassing pseudepiphallus. Ectophallic fold at posterior end produced into two broadly-obtuse lateral lobes (lo), in dorsal view with apical emargination wider between lateral lobes and truncated; ectophallic fold slightly surpassing both lateral lobes. Endophallic sclerite [formula] elongated, typical of genus. Rami very short. Spermatophore rounded to slightly oval.

Measurements (in mm). 2 J: BL = 15.5–18.6; BWL = 24.7–25.6; HL = 1.8–2.5; PronL = 2.7–3.0; PronW = 3.5–3.9; FWL = 17.1–18.1; FWW = 3.7–4.4; HWT = 3.0–3.6; FIIIL = 11.6–12.6; TIIIL = 11.5–12.0.

Ecology. This species was found on the Zea mays (corn) plant, and more commonly found hiding in the corners of the leaves.

Type locality. PHILIPPINES, Mindanao Island , Lanao del Norte, Iligan

Distribution. PHILIPPINES (Mindanao Island: Agusan del Sur, Lanao del Norte and Balingoan)

Calling song (1J, 29±2°C). The calling song consists of echemes made up of 4 or 5 syllables and has an average duration of 0.58±0.08 s (0.52–0.68 s). Each syllable has an average duration of 34.7±2.7 ms (30.7–39.4 ms). The average interval between consecutive syllables is 0.13±0.01 ms (0.12–0.13 ms). The frequency spectrum is pure-tonal and forms a harmonic, with the energy peaking at the fundamental frequency. The dominant frequency is 6.25 kHz.

The calling song of Varitrella (Cantotrella) fuscoirrorata differs from that of Varitrella (Cantotrella) bakeri by the fewer number of syllables within each echeme, even though the syllable duration is similar. The average interval between consecutive syllables of V. (C.) fuscoirrorata is slightly shorter than that of V. (C.) bakeri . The calling song of V. (C.) fuscoirrorata has a higher dominant frequency than that of V. (C.) bakeri (although this may be attributed to the difference in the temperature during recording).

The calling song of Varitrella (Cantotrella) fuscoirrorata is different from those of congeners with known calling songs (i.e., Varitrella (Cantotrella) suikei Tan, Japir & Chung, 2020 and Varitrella (Cantotrella) tabin Tan, Japir, Chung & Robillard, 2022 ) (see Tan et al., 2020a, 2022). The calling song consists of echemes with 4 or 5 syllables, instead of echeme-sequences made up of a few closely-spaced syllables.

Figures

FIGURE 17. Varitrella (Cantotrella) fuscoirrorata comb. nov. ♁ in its natural environment, on the foliage of Zea mays (A); habitus in dorsal (B) and lateral (C) views. Scar bars: 5 mm.

FIGURE 18. Varitrella (Cantotrella) fuscoirrorata comb. nov. ♁: head and pronotum in dorsal (A) and lateral (C) views; face in anterior view (B); FWs in dorsal (D) and lateral (E) views; subgenital plate in ventral view (F). Scale bars: 5 mm (D, E), 2 mm (A–C), 1 mm (F).

FIGURE 19. Varitrella (Cantotrella) fuscoirrorata comb. nov. ♁ genitalia in dorsal (A), ventral (B, C) and lateral (D, E) views. Scale bars: 1 mm.