Ectatoderus dubius Tan, 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 : 343-344

Ectatoderus dubius Tan & Salvador, sp. nov.

( Figs 37–39 )

Specimens examined. Holotype: PHILIPPINES • ♁; Mindanao, Misamis Oriental, Gingoog City, Barangay Lunotan , near Mt Sumagaya ; N8.70132, E125.00980, 1197.0± 7.3 m.a.s.l.; 16 February 2023, 19h44; mossy forest, on a leaf near the ground; coll. M.K. Tan, J.A.G. Salvador, A.M. Sabang, A. Gono, D.C.M. Bahoy & K. Grumo; MIN.23.66 ( PNM) ( Fig. 37 )

Remarks. The generic status of this species is very peculiar and this species could potentially be placed under either Ornebius or Ectatoderus . The male holotype has the TI with a small round inner tympanum and the frontal rostrum about as wide as the scapes; all of which are characteristics of Ornebius and Ectatoderus . The pronotum is strongly produced backwards, leaving only the apex of the tegmen free, which is characteristics of Ectatoderus ; but the male genitalia are more characteristics of an Ornebius species, particularly of species from the species group kanetataki (Matsummura, 1904). Moreover, Ectatoderus has not been recorded in the Philippines. However, based on the generic diagnosis of Ectatoderus ( Ingrisch, 2006) , we tentatively place this species under Ectatoderus . Future phylogenetic work may reveal that this species may belong to another genus (noting that it is likely that Ectatoderus is not monophyletic, see Ingrisch, 2006).

Diagnosis. From the Ectatoderus from Southeast Asia, this new species is characterised by the epiphallus membranous with its lateral valves forming separate lobes; these lobes are weakly sclerotized, with their apices rounded and more sclerotized; the medial valve more strongly sclerotized, curved at the base forming a semi-circle, having its apex pointed.

From Ornebius , this species is characterised by the pronotum very strongly produced posteriorly, covering almost entire FWs. The new species also shares similarities in the pronotum with Ornebius cucullatus (Bolívar, 1889) from Mayon Volcano (in Albay), in the pronotum extending more posteriorly and nearly surpassing the base of the FIII; but differs by the FWs not extending well beyond pronotum and by the mirror covered by the pronotal dorsal disk, and by the pronotal dorsal disk covering almost entirely of the abdomen. It also shares similarities in the pronotum with Ornebius consternus Ingrisch, 2006 from Sulawesi, but differs by the male genitalia without the lateral valves sclerotized, and by not forming a tube near the apex.

Etymology. The species name refers to peculiar generic status.

Description. Small species for the genus; habitus of male as shown in Figs 37 , 38A . Dorsum of head flattened, covered with dark-grey scales ( Fig. 38A ). Frontal rostrum 1.5 times wider than scapes ( Fig. 38A ). scapes dark-grey ( Fig. 38A ); basal antennal segments dark-coloured, thereafter brown with some segments black ( Figs. 38A ). Frons and mouthparts of red brown ( Fig. 38B ). Maxillary palps dark-grey to black; with apical (= fifth), subapical (= fourth) and third segments of subequal lengths; apical segment pyriform ( Fig. 38B ). Head with lateral parts, including genae, of dark colour, without bands ( Fig. 38B ). Pronotal disk brown and wholly covered with dark-grey scales, about 1.7 times longer than wide, with anterior margin narrow and straight; lateral margin widening posteriorly; covering entire mirror of FW; posterior margin convex with white scales ( Fig. 38A ). Pronotum with lateral lobe also wholly covered with dark-grey scales ( Fig. 38B ). TI with internal tympanum small and oval; without external tympanum. FIII 1.2 times as long as TIII; TIII 3.3 times as long as MTaIII ( Fig. 38C ). Fs and Ts generally pale brown, covered with marmoration of dark-grey scales except in basal parts. Tarsi cream-coloured, with apical parts of segments brown. Abdominal tergites and sternites covered with dark-grey scales. Cercus covered with grey scales.

Male. FW mostly infumated yellow brown, dorsal field darker at posterior margin ( Fig. 38A ); lateral field with dorsal half infumated yellow brown and ventral half infumated black and ventral margin white ( Fig. 38B ). Supra-anal plate with last abdominal tergite and epiproct distinctly separated by a transverse suture. Last abdominal tergite transverse. Supra-anal plate less transverse than last abdominal tergite, stout tongue-shaped with apex truncated and straight ( Fig. 38D ). Subgenital plate black, 1.3 times as wide as long, anterior margin concave, posterior margin obtuse with a few long setae. Paraproct process yellow brown, elongate, cylindrical, curved dorsad and tapering into a subacute apex ( Figs 38D, 38E ). Genitalia as in Figs 38F–H . Epiphallus (ep) membranous. Lateral valves (lv) forming separate lobes; lobe weakly sclerotized, apex rounded and more sclerotized. Medial valve (mv) strongly sclerotized, curved at base forming a semi-circle; apex pointed, not reaching apex of lateral valve. Ejaculatory duct (ed) surpassing medial valve and lateral valves.

Female. Unknown.

Measurements (in mm). BL = 8.2; HL = 1.0; PronL = 5.0; PronW = 3.0; FWL = 3.4; FWW = 3.0; FIIIL = 5.0; TIIIL = 4.2; MtaIIIL = 1.3.

Ecology. The species was found in the mossy forest.

Type locality. PHILIPPINES, Mindanao Island, Misamis Oriental, Gingoog City, Barangay Lunotan

Distribution. PHILIPPINES (Mindanao Island: Gingoog City in Misamis Oriental)

Calling song (1J, 23.8°C) ( Fig. 39 ). The calling song is made up of an echeme consisting of 33 syllables and has a duration of 7.55 s. The first few syllables tend to be of lower amplitudes; amplitude of syllable gradually increases to a maximum and stabilises. The syllable duration is 36.1 ms and average interval between consecutive syllables is 204.8 ms. The frequency spectrum is pure-tonal and forms a harmonic, with the energy peaking at the fundamental frequency. The dominant frequency is 5.72 kHz.

Figures

FIGURE 37. Ectatoderus dubius sp. nov. ♁ in its natural environment, a mossy forest near Mt Sumagaya.

FIGURE 38. Morphology and ♁ genitalia of Ectatoderus dubius sp. nov.: habitus (without posterior legs) in dorsal view (A); head, pronotum and FWs in lateral view (B); posterior leg in external view (C); abdominal apex in dorsal (D) and dorso-lateral (E) views; phallus complex in dorsal (F), ventral (G) and lateral (H) views. Scale bars: 2 mm (A, C), 1 mm (B, D–H).

FIGURE 39. Ectatoderus dubius sp. nov. ♁ calling song: oscillograms showing one echeme (A); spectrogram of the same echeme (B); power spectra of a syllable (C) where the grey line represents the power [dB] (axis name and scale in grey) and the black solid peak represents the relative amplitude (axis name in black).