The taxonomy and bioacoustics of the elusive crickets from the genus Pendleburyella Chopard, 1969 (Gryllidae: Pentacentrinae) Author Tan, Ming Kai Block 207 A, Woodleigh Link, Singapore 361207, Republic of Singapore Author Muhammad, Amira Aqilah Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia Author Wahab, Rodzay Bin Haji Abdul Institute for Biodiversity and Environmental Research, Universiti Brunei Darussalam, Jalan Universiti, BE 1410, Brunei Darussalam rodzay. wahab @ ubd. edu. bn; https: // orcid / org / 0000 - 0002 - 2151 - 7709 rodzay.wahab@ubd.edu.bn text Zootaxa 2023 2023-05-01 5277 1 131 148 http://dx.doi.org/10.11646/zootaxa.5277.1.6 journal article 10.11646/zootaxa.5277.1.6 11ad2e19-0175-4b89-8b57-0192c1437803 1175-5326 7893034 CD726173-9C2E-4E33-91BF-DD3D47A791D6 Pendleburyella pimela sp. nov. ( Figs. 4 , 5A , 6A, 6C, 6E , 7C , 8C , 9A–C , 11 ) Diagnosis. This species is characterised by a large-sized habitus, the maxillary palps with the apical segment also triangular (but more stout and broadly widened than Pendleburyella testacea ); the FWs relatively broad (FWL/ FWW <2.4 compared to> 2.5 in other species specimens); the mirror about as long as broad, the dividing vein of the mirror broadly and roundly curved at the basal end, the apical part of the FW shorter relative to the FWL (all of these similar to Pendleburyella vicina but this species is distinctly larger in size). The genitalia differs from that of Pendleburyella eirmosa sp. nov. by the pseudepiphallic lophi, in profile, cylindrical with roundly truncated apices (instead of dorso-ventrally flattened), the pseudepiphallic paramere ventral processes more elongated and in ventral view having acute apices (instead of obtuse apices); and the emargination between the dorsal and ventral processes pseudepiphallic paramere, in profile, narrowly angular (instead of broadly rounded). Etymology. The species name refers to the large habitus and relatively broad FWs (low FWL/FWW); pimele = fat in Greek. Material examined. Holotype : SINGAPORE • 1♁; Nee Soon freshwater swamp forest, along Woodcutter Trail ; on leaf litter; 21 December 2022 ; coll. M.K. Tan & I. Neo ; call recorded; ( ZRC ). FIGURE 7. Pendleburyella ♂ head and pronotum in lateral view: Pendleburyella testacea (A), Pendleburyella vicina (B), Pendleburyella pimela sp. nov. (C), Pendleburyella eirmosa sp. nov. (D), Pendleburyella sp. 1 (E), Pendleburyella sp. 2 (F). Scale bar: 2 mm. Description. Very large species for this genus. Maxillary palpi with apical segment longest and expanded (triangular); with subapical segment cylindrical and expanded slightly distally, somewhat similar length as apical and third segments ( Fig. 7C ). Pronotal disc brown about 2.0 times as wide as long, widening posteriorly (posterior margin about 1.6 times as wide as anterior margin); anterior margin of disc broadly concave; posterior margin of disc slightly convex ( Fig. 6A ). Pronotal lateral lobe 2.3 times as long as high (Fig, 7C). Male. FW 2.4 times as long as broad ( Fig. 8C ), covering abdomen and slightly surpassing apex of FIII. Venation ( Fig. 8C ): 1A vein transverse, faintly curved; diagonal substraight, with 3 distinct oblique veins in harp area; posterior two oblique veins substraight,join at base near1A,anterior most vein distinctly shorter and running nearly perpendicular to 1A. Mirror about 1.1 times as long as wide, dividing vein broadly curved at basal end. Lateral field around 10 branches on Sc ( Fig. 6E ). Apical field 0.09 times as long as FWL ( Fig. 8C ). Hind wings clearly surpassing FWs. FIGURE 8. Pendleburyella ♂ FWs: Pendleburyella testacea (A), Pendleburyella vicina (B), Pendleburyella pimela sp. nov. (C), Pendleburyella eirmosa sp. nov. (D), Pendleburyella “intermedia” (E), Pendleburyella sp. 1 (F), Pendleburyella sp. 2 (G). Scale bar: 2 mm. FIGURE 9. Pendleburyella ♂ genitalia: Pendleburyella pimela sp. nov. (A–C) and Pendleburyella eirmosa sp. nov. (D–F) in dorsal (A, D), ventral (B, E) and lateral (C, F) views. Scale bars: 0.2 mm. ♁ genitalia ( Figs. 9A–C ). Pseudepiphallus [epiphallus] typical of genus. Posterior end of pseudepiphallus [epiphallus] produced into two tongue-shaped lobular pseudepiphallic lophi [posterolateral epiphallic lobe] with obtuse apices. These lophi, in profile, cylindrical with roundly truncated apices. Pseudepiphallic paramere [ectoparamere] very elongated with ventral process well surpassing pseudepiphallic lophi; all processes with apex acute. Dorsal process of pseudepiphallic paramere distinctly shorter than ventral process barely surpassing pseudepiphallic lophi. Ventral process of pseudepiphallic paramere distinctly more sclerotized along inner margin. In profile, emargination between dorsal and ventral processes narrowly angular. Ectophallic fold [rachis] typical of genus; in profile tapering into acute apex, with anterior margin concave and posterior margin straight. FIGURE 10. Pendleburyella vicina ♂ holotype: habitus in dorsal (A) and lateral (B, C) views; labels (D). Scale bars: 2 mm. Measurements (♂, in mm). BL = 9.5; BWL = 13.3; HL = 1.1; PronL = 1.4; PronW = 2.8; FWL = 7.9; FWW = 3.3; HWT = 3.3; FIIIL = 5.4; TIIIL = 3.9; TaIIIL = 1.5. Ecology. The species was found dwelling among thick leaf litter in freshwater swamp forest. Distribution. Malay Peninsula ( SINGAPORE ). Type locality. SINGAPORE Calling song (1♂, in captivity, 29.0°C) ( Fig. 11 ). The male was observed to call between 22h00 and 23h30, each night having 2–4 bouts of continuous trill. The calling song is a loud continuous trill, typically lasting around 2–5 min when left undisturbed. The trill is made up of closely-packed syllables with an average duration of 9.7±1.5 ms (5.9–14.2 ms). The average syllable period is 14.5±0.8 ms (10.8–17.1 ms). There is no distinct downtime between syllables. The frequency spectrum is pure-tonal and forms a harmonic, with the energy peaking at the fundamental frequency. The dominant frequency is 8.14±0.08 kHz (7.78–8.34 kHz).