Tembelingiola biaculeata Tan, Gorochov & Robillard, 2024

Tan, Ming Kai, Gorochov, Andrei, Japir, Razy, Chung, Arthur Y. C. & Robillard, Tony, 2024, New species of little-known crickets from the subfamily Pteroplistinae (Orthoptera, Grylloidea) from Sabah and contribution to their bioacoustics, Zootaxa 5506 (2), pp. 205-226 : 209-212

Tembelingiola biaculeata Tan, Gorochov & Robillard , sp. nov.

( Figs 2A , 3A , 4A , 5 , 6 , 7A–D , 8 )

Material examined. Holotype: EAST MALAYSIA: • ♂; Sabah State, Sandakan District, Sepilok, Rainforest Discovery Centre , dipterocarp forest; N5.87552, E117.94131, 62.6±6.0 m.a.s.l.; 18.v.2022, 22h36; on foliage of shrub near ground; M.K. Tan & T. Robillard leg.; SBH.22.159 ( FRC).

Paratype: EAST MALAYSIA: • ♂; Sabah State, Sandakan District, Sepilok, Rainforest Discovery Centre , dipterocarp forest; N5.87536, E117.93977, 57.6± 6.8 m.a.s.l.; 19.v.2022, 21h06; among branches and twigs; M.K. Tan & T. Robillard leg.; SBH.22.165 ( ZRC) .

Diagnosis. This species differs from Tembelingiola plana Gorochov, 2004 from Peninsular Malaysia by the pseudepiphallic paramere [ectoparamere] thicker (less slender), directed downwards (but not backwards), with acute and hooked apical part; and the ectophallic fold [rachis] narrowing posteriorly into acute apex and slightly surpassing pseudepiphallic bridge.

It also differs from Tembelingiola belaitensis Tan, Gorochov & Wahab, 2019 from Brunei Darussalam by the pseudepiphallic lophi [posterolateral epiphallic lobes] directed partly externally (but not curved internally in distal part); pseudepiphallic parameres [ectoparameres] completely sclerotized and somewhat longer but directed downwards (in T. belaitensis , they are in the form of membranous lobules directed backwards and with thin sclerotized ribbon ventrally); ectophallic fold [rachis] much shorter and less strongly sclerotized; and endophallic sclerite [formula] clearly less wide and not divided into a pair of sclerotized plates.

Etymology. The species name refers to the acute apices at the posterior end of both the pseudepiphallic parameres [ectoparameres]; bi- referring to two (a pair), and aculeatus = with spike in Latin.

Description. Small-sized, body well pubescent, brown with head, pronotum and abdomen with rufous tinge ( Figs 5 , 6 ). Rostrum between antennal cavities 1.1 times wider than scapes ( Fig. 7A ), angularly-rounded in profile ( Fig. 7B ). Maxillary palps pale coloured, with apical, subapical and third segments of subequal lengths; with apical segment elongated-triangular, very broadly expanded apically ( Fig. 7B ). Head wider than high in facial view. Face dark brown ( Fig. 7C ); median ocellus present, round; fenestrae between the scapes, anterior of median ocellus, also round and similar in size as median ocellus. Pronotal dorsal disc densely pubescent, weakly transverse, 1.1–1.3 times as wide as long, faintly widening posteriorly; anterior and posterior margins fairly straight to faintly concave and convex, respectively and with numerous long and thick setae ( Fig. 7A ). Lateral lobe 1.7 times as long as wide; posterior margin oblique, with numerous long and thick setae (more so than other parts of lateral lobe); ventral margin raised posteriorly; vaguely darker than dorsal disc ( Fig. 7B ). Inner tympanum on TI large, elongated oval (opened); outer tympanum undeveloped. TIII with only numerous small dorsal denticles; with 3 pairs of apical spurs, inner ones typically longer than outer ones; hind basitarsus with 2 rows of dorsal spines (each row with 5–6 spines). Legs generally pale brown. FIII pale brown, but distal part and knee dark rufous, and TIII dark rufous.

Male. FW light brown; barely reaching abdominal apex, 1.8–1.9 times as long as wide ( Fig. 7D ). Dorsal field with diagonal vein long and slightly sinuous; 5 oblique veins (3 long, parallel sinusoidal posterior ones and 2 anterior shorter and fainter ones); mirror approximately 1.1 times as wide as long, separated by two dividing veins, dividing veins mostly straight but at anal end slightly bent; with moderately short apical area ( Fig. 7D ). Lateral field of FW with about 9 branches of Sc and 12 cross veins between R and M. Hind wings not exposed ( Fig. 6 ). Thoracic sternites brown. Subgenital plate with apex having an angular notched in the middle.

Genitalia as shown in Fig. 8 . Pseudepiphallus [epiphallus] divided into two lateral parts. Pseudepiphallic lophi [posterolateral epiphallic lobes] dorso-ventrally compressed; basal third broad, after basal third taper and bent externally, with external margins concave; apex roundly truncated. Pseudepiphallic lophi [epiphallic lateral lobes] connected by narrow bridge; pseudepiphallus with anterior part transversely straight. Pseudepiphallic parameres [ectoparameres] strongly sclerotized, elongated, not directed downwards and with hooks apically; hook with apex acute, not reaching apex of pseudepiphallic lophi. Ectophallic fold [rachis] semi-tube-like, approximately triangular with basal part having two lateral plates; ectophallic fold narrowing posteriorly into acute apex and slightly surpassing pseudepiphallic bridge. Endophallic sclerite [formula] lamellate, transverse and strongly sclerotized with lateral tongues at anterior and posterior parts. Rami fused with pseudepiphallus. Additional lateral sclerotized plate (p) elongated-pyriform with posterior apex narrow and subacute.

Female. Unknown

Measurements. • ♂ holotype: BL = 8.9; BWL = 9.6; HL = 1.9; PronL = 2.2; PronW = 2.8; FWL = 5.9; FWW = 3.3; FIIIL = 6.3; TIIIL = 4.0; TaIIIL = 3.1 • ♂ paratype: BL = 8.3; BWL = 9.4; HL = 1.3; PronL = 2.3; PronW = 2.6; FWL = 5.8; FWW = 3.1; FIIIL = 5.9; TIIIL = 3.6; TaIIIL = 3.0.

Ecology. This species occurs in sympatry with Tembelingiola kabili sp. nov. One male individual was found on a foliage of a low-shrub, whereas another male was found on a dead branch ( Fig. 5 ).

Distribution. EAST MALAYSIA: Sabah: Sepilok

Calling song ( Figs 2A , 3A , 4A ). Consists of either short or long echemes. At 31.50–31.75°C, a short echeme has a duration of 0.26± 0.02 s (0.23– 0.29 s) and consists of an average of nine syllables (8–10 syllables). A long echeme has a duration of 3.02± 0.48 s (2.50– 3.77 s) and consists of an average of 101 syllables (82–127 syllables). The silent interval between consecutive echemes is 1.7± 0.8 s (0.9– 3.4 s). Within each echeme, the average syllable duration is 18.8±2.1 ms (14.0–21.9 ms) and the average silent interval between consecutive syllables is 11.1±2.9 ms (7.3–17.3 ms). The frequency spectrum is pure-tonal and forms a harmonics, with the energy peaking at a dominant frequency of 5.66±0.09 kHz (5.53–5.72 kHz).

Figures

FIGURE 2. Power spectra of the calling songs of the pteroplistine cricket species: Tembelingiola biaculeata sp. nov. (A), Tembelingiola kabili sp. nov. (B), Pteroplistes silam sp. nov. (C), Pteroplistes lagrecai Gorochov, 2004 (D) and Singapuriola separata Gorochov & Tan, 2012 (E). 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).

FIGURE 3. Oscillograms of the calling songs of the pteroplistine cricket species: three echemes with different lengths of Tembelingiola biaculeata sp. nov. (A), two echeme-sequencesof Tembelingiola kabili sp. nov. (B), continuous trill of Pteroplistes silam sp. nov. (C), an echeme-sequence of Pteroplistes lagrecai Gorochov, 2004 (D) and three echemes of Singapuriola separata Gorochov & Tan, 2012 (E). Scale bar: 1 s.

FIGURE 4. Oscillograms of the syllables of the pteroplistine cricket species: Tembelingiola biaculeata sp. nov. (A), Tembelingiola kabili sp. nov. (B), Pteroplistes silam sp. nov. (C), Pteroplistes lagrecai Gorochov, 2004 (D) and Singapuriola separata Gorochov & Tan, 2012 (E). Scale bar: 0.05 s.

FIGURE 5. Male Tembelingiola biaculeata sp. nov. in its natural habitat in Sepilok.

FIGURE 6. Habitus of Tembelingiola biaculeata sp. nov., male in dorsal (A) and lateral (B) views. Scale bars: 2 mm.

FIGURE 7. Tembelingiola biaculeata sp. nov. (A–D) and Tembelingiola kabili sp. nov. (E – I): head and pronotum in dorsal (A, E) and lateral (B, F) views, face in anterior view (C, G), male FW in dorsal view (D, H), female FWs in dorsal view (I). Scale bars: 2 mm (D, H, I), 1 mm (rest).

FIGURE 8. Male genitalia of Tembelingiola biaculeata sp. nov. in dorsal (A), ventral (B) and lateral (C) views. Scale bar: 0.5 mm.